Packaging for a sensor and methods of manufacturing thereof

Abstract

Some embodiments of this disclosure relate to a sensor assembly including a substrate having an outer region, an inner region, and an intermediate region between the outer and inner regions. The substrate further includes electrical contact pads located at least in the inner region. The sensor assembly further includes a housing coupled to the substrate at the intermediate or outer region to provide a hermetically sealed seal. The sensor assembly further includes a bare sensor die bonded to the substrate at the inner region. A metal binder bonds the electrodes of the bare sensor die to the electrical contact pads. The metal binder includes platinum and / or one or more metals selected from tin, indium, copper, aluminum, and / or nickel.

Description

Technical Field

[0001] The embodiments disclosed herein generally relate to a sensor for monitoring and controlling, for example, gas flow rate. Prior Technology

[0002] Various manufacturing systems (such as those used in semiconductor applications) may include the measurement of gas flow properties, such as flow rate, temperature, pressure, and similar properties. Sensors used for such measurements may be incompatible with the corrosive environments used in some manufacturing systems, such as corrosive environments, environments with high-energy plasma, environments with vacuum, environments with high temperatures and / or frequent temperature cycling, and similar environments. Fabricating sensors and / or sensor packages with specific geometries that do not adversely affect the process gas properties, while also being compatible with certain corrosive environments, can be a challenge.

[0003] For example, in some manufacturing systems, process gases (e.g., gases used during semiconductor manufacturing processes) and / or cleaning gases (e.g., gases used to clean manufactured equipment and / or to clean chambers used in the manufacture of electronic devices) may have precise delivery targets, including high-quality flow rates and the ability to precisely control low flow rates. Conventional manufacturing systems typically use one or more mass flow controllers (MFCs) to measure and control the mass flow rate of process gases.

[0004] It would be advantageous to develop MFCs and / or other sensors that are compatible with corrosive manufacturing environments (e.g., resistant to corrosion and / or material contamination), maintain vacuum seals, are robust, have long operating lives, are reliable, and have geometries that minimize adverse effects on airflow properties. Summary of the Invention

[0005] Some embodiments of this disclosure relate to a sensor assembly including a substrate, a housing, and a sensor die. In some embodiments, the substrate includes an outer region, an inner region, and an intermediate region positioned between the outer and inner regions. In some embodiments, the substrate further includes electrical contact pads located at least on the inner region. In some embodiments, the housing is coupled to the substrate at the intermediate region or the outer region to provide a hermetically sealed connection. In some embodiments, the sensor die is coupled to the substrate at the inner region via the electrical contact pads. The sensor die is aligned with the substrate via alignment features that align the sensor die relative to the substrate within at least one of a first plane or a second plane.

[0006] In another embodiment of this disclosure, a gas flow sensor configured to be coupled to an airflow tube via a flange includes a dielectric substrate having an outer region, an inner region, and an intermediate region between the outer and inner regions. The dielectric substrate includes electrical contact pads formed between layers of the dielectric substrate. These electrical contact pads extend from the outer region through the dielectric substrate to the inner region. A housing is coupled to the dielectric substrate at the intermediate region to form a hermetically sealed seal. A sensor die is coupled to the dielectric substrate at the inner region via the electrical contact pads. The sensor die is aligned with the dielectric substrate via alignment features that align the sensor die relative to the dielectric substrate at least in a first or second plane.

[0007] In another embodiment of this disclosure, a method includes the following steps: providing a substrate having an outer region, an inner region, and an intermediate region positioned between the outer region and the inner region. The substrate further includes an electrical contact pad located at least on the inner region. The method further includes the step of aligning a sensor die with the substrate at the inner region via one or more alignment features, the one or more alignment features aligning the sensor die relative to the substrate in a first plane or a second plane. The method further includes the step of coupling the sensor die to the substrate at the inner region. The method further includes the step of coupling the substrate to a housing at the intermediate region or the outer region to provide a hermetically sealed connection.

[0008] In another embodiment of this disclosure, a sensor assembly includes a substrate having an outer region, an inner region, and an intermediate region between the outer region and the inner region. The substrate further includes electrical contact pads located at least in the inner region. The sensor assembly further includes a housing coupled to the substrate at the intermediate region or the outer region to provide a hermetically sealed seal. The sensor assembly further includes a bare sensor die bonded to the substrate at the inner region. A metal binder bonds the electrodes of the bare sensor die to the electrical contact pads. The metal binder includes platinum and / or one or more metals selected from tin, indium, copper, aluminum, and / or nickel.

[0009] In another embodiment of this disclosure, a method of manufacturing a sensor assembly includes the following steps: providing a substrate having an outer region, an inner region, and an intermediate region between the outer region and the inner region. The substrate further includes a first electrical contact pad and a second electrical contact pad located at least on the inner region. The method further includes the following steps: providing a sensor die having a first electrode and a second electrode. The first electrode includes a first metal wire extending from the sensor die, and the second electrode includes a second metal wire extending from the sensor die. The method further includes the following steps: positioning the sensor die on the inner region of the substrate such that a portion of the first metal wire covers the first electrical contact pad, and the second metal wire covers the second electrical contact pad. The method further includes the following steps: bonding the first metal wire to the first electrical contact pad by a first welding operation. The method further includes the following steps: bonding the second metal wire to the second electrical contact pad by a second welding operation. The method further includes the following steps: coupling the substrate to a housing in the intermediate region or the outer region of the substrate to provide a hermetically sealed connection.

[0010] In another embodiment of this disclosure, a method for manufacturing a sensor assembly is provided. The method includes the steps of: providing a substrate having an outer region, an inner region, and an intermediate region between the outer region and the inner region. The substrate further includes electrical contact pads located at least in the inner region. The method further includes the step of: providing a sensor die having electrodes. The method further includes the step of: disposing a multilayer reactive foil onto at least one of: a) the electrical contact pads of the substrate, or b) the electrodes of the sensor die. The method further includes the step of: positioning the sensor die onto the inner region of the substrate such that the multilayer reactive foil is sandwiched between the electrical contact pads and the electrodes. The method further includes the step of: igniting the multilayer reactive foil to form a metallic bond between the electrical contact pads of the substrate and the electrodes of the sensor die. The method further includes the step of: coupling the substrate to a housing in the intermediate region or the outer region to provide a hermetically sealed environment.

[0011] In another embodiment of this disclosure, a sensor assembly includes a housing having a first channel and a second channel. The first channel is configured to allow gas to flow in a first direction, and the second channel is configured to allow the gas to flow in a second direction. The housing is configured to be coupled to an airflow assembly. A substrate is disposed within the housing. The substrate has an outer region, an inner region, and an intermediate region, the inner region being located within the first channel, and the intermediate region being located between the outer region and the inner region. The substrate further includes electrical contact pads located at least on the inner region. A sensor die is coupled to the inner region of the substrate and has electrical connection to the electrical contact pads. The sensor die is disposed within the airflow path of the first channel.

[0012] In another embodiment of this disclosure, a gas stick assembly includes a first end having an input configured to receive gas from a gas source. The gas stick assembly further includes a second end having an output configured to deliver the gas to a destination. The gas stick assembly further includes a valve between the first end and the second end. The gas stick assembly further includes a sensor assembly between the first end and the second end. The sensor assembly includes a housing having a first channel and a second channel, the first channel being configured to receive gas from an upstream component of the gas stick assembly, and the second channel being configured to guide the gas to a downstream component of the gas stick assembly. The sensor assembly further includes a substrate within the housing. The substrate has an outer region, an inner region, and an intermediate region, the inner region being located within the first channel, and the intermediate region being located between the outer region and the inner region. The substrate further includes electrical contact pads located at least on the inner region. The sensor assembly further includes a sensor die coupled to the inner region of the substrate and having electrical connections to the electrical contact pads. The sensor die is positioned within the airflow path of the first channel.

[0013] In another embodiment of this disclosure, a processing apparatus includes a processing chamber, a plurality of gas suppliers, and a plurality of gas rod assemblies. Each of the gas rod assemblies is coupled between the processing chamber and a corresponding gas supplier among the plurality of gas suppliers. Each gas rod assembly includes a first end having an input configured to receive gas from the corresponding gas supplier coupled to the gas rod assembly. The gas rod assembly further includes a second end having an output configured to deliver the gas to the processing chamber. The gas rod assembly further includes a valve between the first end and the second end. The gas rod assembly further includes a sensor assembly between the first end and the second end. The sensor assembly includes a housing having a first channel and a second channel, the first channel being configured to receive the gas from an upstream component of the gas rod assembly, and the second channel being configured to direct the gas to a downstream component of the gas rod assembly. The sensor assembly further includes a substrate within the housing. The substrate has an outer region, an inner region, and an intermediate region, the inner region being located within the first channel, and the intermediate region being located between the outer region and the inner region. The substrate further includes electrical contact pads located at least in the internal region. The sensor assembly further includes a sensor die coupled to the internal region of the substrate and having electrical connection with the electrical contact pads. The sensor die is disposed within the airflow path of the first channel. Simple Explanation of the Diagram

[0014] The present disclosure is illustrated in the accompanying drawings by way of example rather than limitation, in which similar reference numerals denote similar elements. It should be noted that different designations for "a / one" embodiment in the present disclosure do not necessarily refer to the same embodiment, and such designation refers to at least one.

[0015] Figure 1 illustrates an exemplary system according to an embodiment of the present disclosure, the system including a processing chamber, a gas source, and a flow control device. Figure 1 also provides an exemplary illustration of how sensor components according to an embodiment of the present disclosure can be incorporated into various locations within the processing chamber and / or manufacturing system.

[0016] Figure 2 illustrates an exemplary flow control device according to an embodiment of this disclosure.

[0017] Figure 3 illustrates an exemplary sensor device that can be used in a sensor assembly according to an embodiment of this disclosure.

[0018] Figure 4A illustrates a perspective view of a sensor assembly according to an embodiment of this disclosure.

[0019] Figure 4B shows an enlarged view of region A in Figure 4A.

[0020] Figure 4C illustrates a cross-sectional side view of an exemplary flow channel according to an embodiment of the present disclosure, on which the sensor assembly of Figure 4A is mounted.

[0021] Figure 4D illustrates a cross-sectional view of a conformal coating formed on the surface of an exemplary sensor assembly according to an embodiment of the present disclosure.

[0022] Figure 5A illustrates a perspective view of a sensor assembly according to an embodiment of this disclosure.

[0023] Figure 5B shows an enlarged view of region B in Figure 5A.

[0024] Figure 5C illustrates a perspective view of a multilayer ceramic substrate included in the sensor assembly of Figure 5A, according to an embodiment of the present disclosure.

[0025] Figure 5D illustrates a side view of the multilayer ceramic substrate of Figure 5C.

[0026] Figure 5E illustrates a top view of the multilayer ceramic substrate shown in Figure 5C.

[0027] Figure 5F illustrates a cross-sectional side view of an exemplary flow channel according to an embodiment of the present disclosure, on which the sensor assembly of Figure 5A is mounted.

[0028] Figure 6A illustrates a perspective view of a sensor assembly according to an embodiment of this disclosure.

[0029] Figure 6B shows an enlarged view of region C in Figure 6A.

[0030] Figure 6C illustrates a perspective view of a substrate included in the sensor assembly of Figure 6A, according to an embodiment of the present disclosure.

[0031] Figure 6D illustrates a cross-sectional side view of an exemplary flow channel having the sensor assembly of Figure 6A, according to an embodiment of the present disclosure.

[0032] Figure 7A illustrates a perspective view of a sensor assembly according to an embodiment of this disclosure.

[0033] Figure 7B illustrates a perspective view of a multilayer ceramic substrate included in the sensor assembly of Figure 7A, according to an embodiment of the present disclosure, wherein the multilayer ceramic substrate is coupled to the sensor device in an internal region.

[0034] Figure 7C illustrates a side view of the multilayer ceramic substrate of Figure 7B.

[0035] Figure 7D illustrates a top view of the multilayer ceramic substrate shown in Figure 7B.

[0036] Figure 7E illustrates the front view of section AA in Figure 7A.

[0037] Figure 8A illustrates a perspective view of a sensor assembly according to an embodiment of this disclosure.

[0038] Figure 8B illustrates the front view of cross section BB in Figure 7E.

[0039] Figure 9A illustrates a perspective view of a sensor assembly according to an embodiment of this disclosure.

[0040] Figure 9B illustrates a perspective view of a multilayer ceramic substrate included in the sensor assembly of Figure 9A, according to an embodiment of the present disclosure, wherein the multilayer ceramic substrate is coupled to the sensor device in an internal region.

[0041] Figure 9C illustrates the front view of section CC in Figure 9A.

[0042] Figure 10A illustrates a perspective view of a sensor assembly according to an embodiment of this disclosure.

[0043] Figure 10B illustrates a perspective view of a multilayer ceramic substrate included in the sensor assembly of Figure 10A, according to an embodiment of the present disclosure.

[0044] Figure 10C illustrates the front view of section DD in Figure 10A.

[0045] Figure 10D illustrates a cross-sectional side view of a sensor assembly according to an embodiment of this disclosure.

[0046] Figure 11A illustrates a flowchart of a method for adapting a sensor device for use in a flow control apparatus according to an embodiment of the present disclosure.

[0047] Figure 11B illustrates a flowchart of a method for manufacturing a sensor assembly according to an embodiment of the present disclosure.

[0048] Figure 11C illustrates method 1200 from Figure 11B.

[0049] Figures 12A-B illustrate a cross-sectional side view of an exemplary flow channel in accordance with the present disclosure, on which a sensor assembly is mounted.

[0050] Figure 13A illustrates a cross-sectional side view of a connector / flange, a multilayer ceramic substrate, and a sensor device according to an embodiment of this disclosure.

[0051] Figure 13B illustrates a disassembled cross-sectional side view of the connector / flange, multilayer ceramic substrate, and sensor device according to an embodiment of this disclosure.

[0052] Figure 14A illustrates a side view of a ceramic substrate and a sensor device according to an embodiment of this disclosure.

[0053] Figure 14B illustrates a disassembled side view of a ceramic substrate and a sensor device according to an embodiment of this disclosure.

[0054] Figure 14C illustrates a partial bottom view of a ceramic substrate and a sensor device according to an embodiment of this disclosure.

[0055] Figure 14D illustrates a partial bottom view of the disassembled ceramic substrate and sensor device according to an embodiment of the present disclosure.

[0056] Figures 15A-G illustrate systems for bonding sensor devices to ceramic substrates according to embodiments of this disclosure.

[0057] Figures 16A-C illustrate flowcharts of a method for manufacturing a sensor assembly according to an embodiment of this disclosure.

[0058] Figures 16D-F illustrate flowcharts of a method for bonding a sensor device to a substrate according to an embodiment of the present disclosure.

[0059] Figure 17A illustrates a perspective view of a sensor assembly according to an embodiment of this disclosure.

[0060] Figure 17B illustrates the front view of section EE in Figure 17A.

[0061] Figure 17C illustrates the disassembled front view of section EE in Figure 17A.

[0062] Figure 17D illustrates the front view of section FF in Figure 17A.

[0063] Figure 17E illustrates a perspective view of a sensor assembly according to an embodiment of this disclosure.

[0064] Figure 17F shows the front view of section GG in Figure 17F.

[0065] Figure 17G illustrates a cross-sectional view of a sensor assembly according to an embodiment of this disclosure.

[0066] Figure 17H ​​illustrates a schematic diagram of a sensor assembly coupled to a gas rod assembly according to an embodiment of the present disclosure.

[0067] Figure 17I illustrates a perspective view of a sensor assembly coupled to a gas rod assembly according to an embodiment of the present disclosure.

[0068] Figure 18 is a block diagram illustrating a computer system used in an embodiment according to the present disclosure. Implementation

[0069] The embodiments described herein relate to a sensor assembly (also referred to as a sensor package) adapted for use in a mass flow control device, a system for incorporating the sensor assembly, a method for adapting the sensor assembly for such use, and a method for using the sensor assembly. In some embodiments, the sensor assembly may also be adapted for uses other than as part of a mass flow control device. For example, the sensor assembly may be adapted for temperature control, pressure control, and similar uses. In some embodiments, the sensor assembly includes a sensing device (e.g., a MEMS device, a hot-wire anemometer (HWA) device, or any other suitable sensor) having a self-contained sensing element to be directly disposed in the flow path of an airflow channel. In some embodiments, the sensor assembly further includes a substrate (e.g., a ceramic substrate) on which the sensing device is fixed (e.g., via a metal adhesive or seal). In some embodiments, the sensor assembly further includes a housing on which the substrate is fixed (e.g., via a metal seal). In some embodiments, the sensor device may be secured to a substrate via a metal adhesive (e.g., by welding, fusion, using multilayer reactive foil, or brazing with a brazing alloy), and the substrate may be secured to a housing via another metal adhesive or seal (e.g., by soldering, welding, or brazing with a brazing alloy). In some embodiments, an O-ring may be further provided between the substrate and the housing. In some embodiments, the various components of the sensor assembly are assembled together to provide a hermetically tight seal between the substrate (on which the sensor device is secured) and the housing (on which the substrate is secured at an outer region or a middle region of the substrate). In some embodiments, the various components of the sensor assembly may be interconnected to establish continuous conductivity from the independent sensing element, through the sensor assembly, to one or more external devices (e.g., processing devices), allowing properties measured by the sensing element to be transferred to the processing device. The various components of the sensor assembly may also be interconnected to minimize the turbulent effects of flow on sensor measurements and / or to provide a hermetically tight seal to accommodate high vacuum and minimize degassing or leakage. In some embodiments, the sensor assembly also includes a conformal coating (on a portion of the assembly or over the entire assembly) to protect various parts of the sensor assembly from corrosive gases.

[0070] Generally, precise control of the temperature and flow rate of process gases used in manufacturing is advantageous for better process control and for meeting precise processing constraints. The low transient response rate of current flow sensors is unsuitable for applications that benefit from precise control of gas dosage, such as the delivery of small volumes of gas or the continuous pulse delivery of one or more gases.

[0071] The embodiments disclosed herein advantageously overcome the limitations of current sensors by utilizing sensing devices (e.g., MEMS devices, hot-wire anemometers (HWA), or any other suitable sensors) located directly within the gas flow path to provide rapid and accurate flow feedback. In addition to flow feedback, the sensing devices can also be advantageously used to provide rapid and accurate temperature measurements at any location in the gas supply line, including at the source, near valves, near the inlet of the process chamber (e.g., delivery point), within the process chamber, or in the foreline. A processing device that monitors the temperature measurements in real time can then transmit power output commands to heating units at different locations in the gas supply line.

[0072] Some embodiments advantageously adapt the sensor device for direct insertion into the airflow path while protecting it from corrosive chemicals. For example, embodiments described herein relate to sensor assemblies and materials for the sensor assembly that can be exposed to corrosive chemicals, such as those used during semiconductor processing. The sensor assembly described herein can be adapted to protect the sensor device from corrosive chemicals while still preserving its electrical properties (e.g., establishing conductivity to the sensor), relative shape, and geometry. In one embodiment, a sensing element (e.g., a nanowire portion) is positioned within the sensor device, exposed to the flow path, and can provide accurate measurement of gas flow rate. The sensor assembly can also be adapted to minimize the turbulent effects of flow on the sensor device's measurements, minimize corrosion, minimize deposition on the sensor die that could impair sensor performance, minimize degassing or leakage to the external environment, maintain vacuum, maintain thermal properties, maintain the sensitivity and / or measurement accuracy of the sensor device, and maintain a fast response of the sensor device.

[0073] In some embodiments, the sensor die and / or the substrate bonded to the sensor die includes one or more alignment features to facilitate alignment of the sensor die and the substrate in one or more planes. For example, a first alignment feature (e.g., alignment pins and / or holes) may be used to align the sensor die and the substrate in a first plane perpendicular to the interface between the sensor die and the substrate. Additionally or alternatively, a second alignment feature (e.g., a thickness-controlled solder joint) may be used to align the sensor die and the substrate in a second plane parallel to the interface between the sensor die and the substrate. The first alignment feature and / or the second alignment feature and / or the third alignment feature (e.g., a recess in the substrate, sized to accept at least a portion of the sensor die) may additionally or alternatively cause the sensor die to be positioned at a target location on the substrate, such that the sensor die is then centered in the gas channel after assembly. These one or more alignment features may facilitate centering and / or placement of the sensor die at the target location, with the sensor die rotated and / or tilted relative to the target of the substrate. The configuration of the sensor assembly can be optimized by carefully controlling the placement, rotation, tilt, and / or orientation of the sensor die relative to the substrate (and therefore relative to the airflow path in which the sensor assembly will be used). Slight variations in the rotation, tilt, and / or placement of the sensor die on the substrate can significantly affect measurements due to phenomena such as turbulence in the airflow path. By ensuring minimal tilting, rotation, and / or that the sensor die is centered in the airflow path, turbulence effects can be minimized, and repeatability between sensors can be improved.

[0074] In some embodiments, the sensor die is bonded to the substrate via a metal adhesive (e.g., brazing and / or soldering) between the electrical contact pads of the substrate and the electrodes of the sensor die. The metal adhesive may include platinum, tin, indium, copper, aluminum, or nickel. For example, in embodiments where the sensor assembly will be used in a corrosive environment (e.g., an environment containing chlorine, bromine, etc.), the metal adhesive may include platinum, aluminum, or nickel. In benign environments (e.g., non-corrosive environments), tin, indium, or copper may be used for the metal adhesive. In some embodiments, the metal adhesive may include layers of aluminum and nickel. For example, a multilayer reactive foil comprising multiple alternating layers of aluminum and nickel may be disposed between the electrodes of the sensor die and the electrical contact pads of the substrate. The foil may be ignited, causing the foil to react and bond the electrodes and electrical contact pads. To enhance the metal adhesive, in some embodiments, a metal adhesive layer may be added to the electrodes of the sensor die or to the electrical contact pads of the substrate. The metal adhesive layer may include an aluminum layer deposited on the electrodes or electrical contact pads. The metal adhesive layer may facilitate bonding the foil to the electrodes and / or electrical contact pads. Alternatively, in some embodiments, the metal binder comprises metal wires bonded to the electrodes of the sensor die and the electrical contact pads of the substrate. The metal wires may be platinum wires. The metal binder can reliably bond the sensor die to the substrate and establish a reliable electrical connection between the sensor die and the substrate. Furthermore, in some embodiments, the metal binder may be substantially corrosion-resistant, thereby allowing the sensor assembly to be used in corrosive environments (e.g., environments with corrosive gases). In corrosive environments, degradation of the electrical connection can have a significant impact on sensor measurements. By ensuring that the sensor die is reliably and / or corrosion-resistantly bonded to the substrate with a metal binder, the sensor assembly can be effectively used in corrosive environments without being adversely affected by corrosion.

[0075] In some embodiments, the housing of the sensor assembly includes a first channel for allowing gas to flow in a first direction and a second channel for allowing gas to flow in a second direction. A bare sensor die may be disposed in the first channel and coupled to a substrate. The housing may be configured to be coupled to the base of the gas spring assembly by one or more fasteners (e.g., threaded fasteners). The bottom surface of the housing may be configured to interface with the gas spring assembly. The housing may be further configured to couple with auxiliary components of the gas spring assembly (e.g., valves, filters, mass flow controllers, etc.). The top surface of the sensor assembly may be configured to interface with the auxiliary components. In some embodiments, the housing may be configured to couple between the base of the gas spring assembly and the auxiliary components. In some embodiments, the channels of the housing include openings on the top surface and the bottom surface of the housing. The openings may have areas for receiving sealing components (e.g., O-rings, seals, etc.) to seal the interface between the housing and the base of the gas spring assembly, and / or the interface between the housing and the auxiliary components. In some embodiments, the sensor assembly includes multiple sensors (e.g., flow sensors, temperature sensors, pressure sensors, etc.). In some embodiments, the sensor housing includes a third channel that connects the first and second channels within the housing. The housing can be configured to receive a plug to close the openings of the first and second channels on the top surface of the housing, thereby directing airflow from the first channel through the third channel to the second channel. The sensor assembly can be included within the air rod assembly by configuring the housing to couple with it. For example, a component of the air rod assembly (e.g., a valve or filter) can be decoupled from the air rod assembly, and the sensor assembly can be coupled to the air rod assembly to replace that component. Therefore, the sensor assembly can be substantially modular (e.g., easily coupled to the air rod assembly in multiple different locations). Furthermore, in some embodiments, the component can be coupled to the top of the sensor assembly. This sensor system allows for easy integration of the sensor assembly into the air rod assembly and further provides rapid replacement of the sensor assembly on the air rod assembly. Furthermore, the sensor assembly can be substantially resistant to the effects of corrosive gases encountered by the air rod assembly, resulting in a longer lifespan for the sensor assembly than conventional systems or assemblies.

[0076] Figure 1 illustrates a system 100 according to an embodiment of this disclosure, the system including a processing chamber 101, a gas source 160, and a flow control device 200. The processing chamber 101 can be used for processes that provide a corrosive plasma environment. For example, the processing chamber 101 can be a chamber for a plasma etcher or plasma etching reactor, a plasma cleaner, etc. In alternative embodiments, other processing chambers may or may not be exposed to a corrosive plasma environment. Some examples of chamber components include chemical vapor deposition (CVD) chambers, physical vapor deposition (PVD) chambers, ALD chambers, IAD chambers, etching chambers, and other types of processing chambers. In some embodiments, the processing chamber 101 can be any chamber used in an electronic device manufacturing system.

[0077] In one embodiment, the processing chamber 101 includes a chamber body 102 and a showerhead 130, which surround an internal volume 106. The showerhead 130 may include a showerhead base and a showerhead gas distribution plate (GDP), and may have multiple gas delivery holes 132 (also referred to herein as channels) throughout the GDP. Alternatively, the showerhead 130 may be replaced by a cap and nozzle in some embodiments, or by multiple pie-shaped showerhead compartments and a plasma generation unit in other embodiments. The chamber body 102 may be made of aluminum, stainless steel, or other suitable materials (e.g., titanium). The chamber body 102 generally includes sidewalls 108 and a bottom 110.

[0078] An outer liner 116 may be disposed near the sidewall 108 to protect the chamber body 102. The outer liner 116 may be manufactured to include one or more holes. In one embodiment, the outer liner 116 is made of alumina.

[0079] An exhaust port 126 may be defined within the chamber body 102 and may couple the internal volume 106 to a pump system 128. The pump system 128 may include one or more pumps and throttle valves for evacuating and regulating the pressure of the internal volume 106 of the processing chamber 101.

[0080] Gas source 160 may be coupled to processing chamber 101 to supply process gas and / or cleaning gas to internal volume 106 via supply conduit 112 and showerhead 130. Flow control device 200 may be coupled to gas source 160 and processing chamber 101. Flow control device 200 may be used to measure and control the gas flow rate from gas source 160 to internal volume 106. An exemplary flow control device 200 will be described in more detail below with reference to FIG2. In some embodiments, one or more gas panels 160 may be coupled to processing chamber 101 to supply gas to internal volume 106. In this embodiment, one or more flow control systems 200 may be coupled to each gas source 160 and processing chamber 101. In other embodiments, a single flow control device 200 may be coupled to one or more gas panels 160. In some embodiments, flow control device 200 may include a flow ratio controller to control the gas flow rate to processing chamber 101 (e.g., via one or more supply conduits 112) or to other processing chambers.

[0081] In some embodiments, a separate flow control device 200 is used for each type of gas supplied to the processing chamber. In embodiments, each flow control device 200 is or includes a gas rod assembly, as described and illustrated below with reference to Figures 17H-I.

[0082] The showerhead 130 can be supported on the side wall 108 of the chamber body 102. The showerhead 130 (or cover) can be opened to allow access to the internal volume 106 of the processing chamber 101 and can provide a seal to the processing chamber 101 when closed. A gas source 160 can be coupled to the processing chamber 101 to supply process gas and / or cleaning gas to the internal volume 106 via the showerhead 130 or the cover and nozzle (e.g., via the orifice of the showerhead or the cover and nozzle).

[0083] In some embodiments, one or more sensor components 170 may be disposed within the internal volume 106. For example, one or more sensor components 170 may be located near the shower head 130 (e.g., within 10 cm). As another example, one or more sensor devices may be located near the substrate 144 (e.g., within 10 cm), which can be used to monitor conditions near the reaction site.

[0084] In one embodiment, the substrate support assembly 148 includes a base 152 that supports an electrostatic chuck 150. The electrostatic chuck 150 further includes a thermally conductive base and an electrostatic puck bonded to the thermally conductive base by an adhesive, which in one embodiment may be a silicone adhesive. The thermally conductive base and / or electrostatic puck of the electrostatic chuck 150 may include one or more optional embedded heating elements, embedded heat insulators, and / or conduits to control the lateral temperature profile of the substrate support assembly 148. The electrostatic puck may further include multiple gas channels, such as recesses, mesa, and other surface features that may be formed in the upper surface of the electrostatic puck. The gas channels may be fluidly coupled to a source of a heat-conducting (or back-side) gas (e.g., helium) via holes drilled in the electrostatic puck. In operation, the back-side gas may be supplied to the gas channels at a controlled pressure to enhance thermal conduction between the electrostatic puck and the supported substrate 144. The electrostatic chuck 150 may include at least one clamping electrode controlled by a clamping power supply.

[0085] Figure 2 illustrates a flow control device 200 according to an embodiment of this disclosure. The flow control device 200 can be configured to measure and control the mass flow rate of process gases and / or cleaning gases used in a manufacturing system, and thus can be considered a type of MFC. The flow control device 200 can be coupled to a gas source 160 and a chamber 101 via an airflow passage 240. The airflow passage can correspond to the supply pipe 112 of Figure 1. In some embodiments, the flow control device 200 can be incorporated into a flow ratio controller or a pulsed mass flow system. In some embodiments, the flow control device 200 can be part of a gas rod assembly, as illustrated below with reference to Figures 17H-I.

[0086] In some embodiments, the flow control device 200 may include at least a flow modulator 210, a sensor assembly 220, and a processing device 230. Gas from the gas source 160 flows through the flow modulator 210 through a flow path 242 defined by the airflow channel 240 and into the chamber 101. In other embodiments, the gas flow channel 240 may terminate outside the chamber 101. For example, the gas flow channel 240 may deliver gas to an open environment (e.g., an exhaust system) or a closed environment (e.g., a building or vehicle ventilation system). In some embodiments, the gas flow channel 240 is a gas conduit, a branch of a gas conduit, or a separate component with its inlet and outlet mounted on a gas conduit.

[0087] In some embodiments, the flow modulator 210 is configured to limit the gas flow rate through the flow path 242 and may include one or more flow modulation valves, each of which may be an actuable valve, such as an electric solenoid valve or a piezoelectric valve. In some embodiments, in addition to valves, the flow modulator may include other components, such as flow or temperature sensing components. In some embodiments, the flow modulator 210 functions as a micro-cuperator (MFC), such as a thermal MFC, a pressure-based MFC, or a decay rate-based MFC.

[0088] In some embodiments where the flow modulator 210 functions as a thermally based MFC, the flow modulator 210 includes a capillary bypass channel that branches off from the gas flow channel 240. Temperature sensors at the beginning and end of the capillary are used to calculate (e.g., by processing device 230 or onboard processing device) a temperature difference that is proportional to the gas flow rate.

[0089] In some embodiments, sensor assembly 220 is disposed downstream of flow modulator 210. Sensor assembly 220 may be part of flow modulator 210 (e.g., adjacent to the flow modulation valve of flow modulator 210), close to flow modulator 210 (e.g., within 10 cm thereof), close to chamber 101 or the inlet of shower head 130 (e.g., within 10 cm thereof), or within chamber 101 (as illustrated in Figure 1 with respect to sensor assembly 170, which may be the same as or similar to sensor assembly 220).

[0090] In some embodiments, sensor assembly 220 includes sensor device 222, which can be configured to generate one or more signals in response to airflow conditions. For example, sensor device 222 can be configured to generate one or more signals indicating gas temperature or gas flow rate. Exemplary sensor assemblies are described in more detail below with reference to Figures 4A to 10C. In some embodiments, sensor assembly 220 is coupled to airflow channel 240 such that sensor device 222 is directly inserted into flow path 242. Sensor assembly 220 is coupled to airflow channel to form a seal to prevent gas leakage. In some embodiments, sensor assembly 220 also includes a housing, a substrate, and sensor device 222 (e.g., a MEMS device, hot-wire anemometer (HWA)) secured to the housing via a seal (e.g., a metal seal).

[0091] In some embodiments, processing device 230 includes a central processing unit (CPU), microcontroller, programmable logic controller (PLC), system-on-a-chip (SoC), server computer, or other suitable type of computing device. Processing device 230 may be configured to execute programmed instructions related to the operation of flow modulator 210. Processing device 230 receives feedback signals from sensor device 222 and optionally flow modulator 210, and calculates the temperature, flow rate, and / or other parameters of the airflow. Processing device 230 further transmits control signals to flow modulator 210 based on the received feedback signals. In some embodiments, processing device 230 is configured for high-speed feedback processing and may include, for example, EPM. In some embodiments, processing device 230 is configured to use chamber 101 to perform a process recipe, or one or more steps of a process recipe, for a manufacturing process. For example, a recipe may specify that an airflow at a specific flow rate occurs at a specific time, lasts for a specific duration, and is specific to a particular gas. As another example, a recipe may specify a pulse of one or more gases.

[0092] Figure 3 illustrates a top view of an exemplary sensor device 300, which can be manufactured using manufacturing techniques familiar to those skilled in the art. The sensor device 300 includes a support structure 302 having a substantially planar shape. The support structure 302 may be formed of an insulating material or a semiconductor, such as silicon, silicon with one or more oxide layers formed thereon, or any other suitable material.

[0093] In some embodiments, the sensor device 300 includes an interface region (interface region 304) at one end of the sensor device and a sensor region (e.g., sensor region 306) at the other end of the sensor device. The interface region 304 may be adapted to couple the sensor device 300 to an external device (e.g., a ceramic substrate or other substrate), for example via electrical contact pads on the substrate (as will be described in further detail with reference to Figures 4A to 10D and Figures 15A-G). The sensor region 306 may define a cavity 312 through which a freestanding sensing element 308 is suspended.

[0094] Figure 3 also illustrates electrical contacts 314 (also referred to as electrodes) extending from one end of the sensing device 300 (e.g., one end of the interface region 304) to the other end of the sensing device 300 (e.g., the other end on the sensing region 306) and / or to the sensing element 308. The sensing element 308 may be suspended between two electrical contacts 314. In one embodiment, the sensing element 308 may be a nanowire. The electrical contacts 314 may be formed of one or more conductive metals. In some embodiments, the sensing element 308 may be made of the same conductive metal as the electrical contacts 314. In one embodiment, the sensing element 308 and / or the electrical contacts 314 may be made of platinum. Electrodes may be used as electrical contacts, and one or more devices (e.g., processing device 230) may be operatively coupled to these electrical contacts. In some embodiments, a portion of the electrical contacts 314 may be fixed to a substrate (e.g., a ceramic substrate), as will be described in further detail with respect to the exemplary sensing assembly described in Figures 4A through 10D. Electrical contact 314 can be used as an electrical contact for interfacing with such external devices, thereby forming a closed circuit during operation.

[0095] Certain embodiments described herein advantageously adapt sensor devices (such as the sensor device described in FIG. 3 (or any other suitable sensor device)) to be directly inserted into airflow channels (such as airflow channel 240 in FIG. 2) while protecting the sensor devices from corrosive gases (e.g., halogen-containing gases such as C₂F₆, SF₆, SiCl₄, HBr, NF₃, CF₄, CHF₃, CH₂F₃, F, NF₃, Cl₂, CCl₄, BCl₃, SiF₄, etc., and other gases such as O₂ or N₂O) that may be utilized in the processing chamber (e.g., processing chamber 101). Further embodiments described herein advantageously adapt sensor devices (such as the sensor device described in FIG. 3 (or any other suitable sensor device)) to include a housing configured to be mounted on an air bar assembly. The housing of such a sensor device may include one or more channels that provide an airflow path across the sensing element of the sensor bare die. In embodiments, such a sensing device can be similarly protected from corrosive gases (e.g., halogen-containing gases such as C₂F₆, SF₆, SiCl₄, HBr, NF₃, CF₄, CHF₃, CH₂F₃, F, NF₃, Cl₂, CCl₄, BCl₃, SiF₄, etc., and other gases such as O₂ or N₂O) that may be utilized in the processing chamber (e.g., processing chamber 101).

[0096] In one example, the embodiments described herein relate to a sensor assembly and materials for the sensor assembly that may be exposed to corrosive chemicals, such as those used during semiconductor processing. The sensor assembly described herein can be adapted to protect the sensor device from corrosive chemicals while still maintaining the electrical properties, relative shape, and geometry of the sensor device. The sensor assembly can also be adapted to minimize the turbulent effects of flow on the sensor device's measurements (e.g., by carefully controlling the orientation and / or position of the sensor die relative to the substrate using one or more alignment features), minimize degassing or leakage to the external environment, maintain vacuum, maintain thermal properties, maintain the sensitivity and / or measurement accuracy of the sensor device, and maintain the fast response of the sensor device. In some embodiments, the sensor assembly / package described herein enables the use of fast-response sensor devices (e.g., fast-response MEMS-based hot-wire silicon flow sensors) in corrosive environments. In some embodiments, the packaging described herein enables the packaging and hermetically sealing of sensor devices (e.g., fast-response MEMS-based hot-wire silicon flow sensors) and / or sensor components without leakage to the external environment (e.g., leakage of vacuum and / or corrosive gases). In some embodiments, the sensor component / packaging described herein enables the positioning of sensor devices to maximize performance while avoiding turbulence effects. In some embodiments, the sensor component / packaging described herein enables the symmetrical positioning of sensor devices at the center of the flow path. In some embodiments, the sensor component / packaging described herein enables the optimization of coating thickness to reduce the impact on the sensitivity of the sensor device. The benefits of this component / packaging include the ability to use fast-response sensor devices (e.g., fast-response MEMS-based hot-wire silicon flow sensors) in corrosive environments, while doing so in a compact (size-based) and cost-effective manner. This can advantageously provide rapid and accurate measurements of gas flow and temperature almost anywhere in the tool (e.g., anywhere in the processing chamber).

[0097] Figure 4A illustrates a perspective view of a sensor assembly 400 according to an embodiment of this disclosure. In one or more embodiments, the sensor assembly (e.g., sensor assembly 400) includes a substrate (e.g., substrate 402). In embodiments, substrate 402 may be a ceramic substrate. In some embodiments, the substrate (e.g., substrate 402) includes an outer region (e.g., outer region 402O) for coupling the substrate to a housing (e.g., housing 404), an inner region (e.g., inner region 402I) for coupling a sensor device (e.g., sensor device 300) to the substrate, and an intermediate region (e.g., intermediate region 402M) located between the outer region and the inner region. The term "outer region" as used herein with respect to substrate 402 or any substrate described in any other figure refers to the region of the substrate adjacent to the external environment outside the gas flow channel 240. The term "inner region" as used herein with respect to substrate 402 or any substrate described in any other figure refers to the region of the substrate adjacent to the internal environment inside the gas flow channel 240. The term "intermediate region" as used herein with respect to substrate 402 or any other substrate described in any other illustration refers to the region of the substrate between the outer region and the inner region. In embodiments, the intermediate region may be used to couple substrate 402 to housing 404.

[0098] In some embodiments, the substrate may be made of a dielectric material, such as sapphire. Sapphire may be a suitable substrate material because it has good corrosion resistance and can be machined into suitable shapes. In some embodiments, the substrate is a ceramic substrate. In some embodiments, the dielectric substrate (e.g., a sapphire substrate) can be machined into suitable shapes according to methods known to those skilled in the art. In some embodiments, the substrate 402 may have an elongated shape (e.g., a cylindrical shape) with rounded edges. In some embodiments, the substrate 402 has a cylindrical shape in at least a portion of its outer region 402O and its middle region 402M, the cylindrical shape transitioning to a semi-cylindrical shape in its inner region 402I.

[0099] In some embodiments, the substrate (e.g., substrate 402) may further include electrical contact pads (e.g., electrical contact pad 414) located at least in an inner region of the substrate. In one embodiment, substrate 402 includes electrical contact pads 414 on a flat surface of a semi-cylindrical shape in the inner region 402I. Electrical contacts 314 on the interface region of the sensing device 300 may be attached to electrical contact pads 414 in the inner region of the substrate (e.g., via metal seals or adhesives). The electrical contacts 314 on the sensing device, together with the electrical contact pads 414 on the substrate and one or more external devices (e.g., processing device 230), form a closed circuit during operation. The electrical contact pads (e.g., 414) on the substrate may be made of the same conductive material as the electrical contact pads 314 on the sensing device. For example, in one embodiment, the electrical contact pads 414 are made of platinum and may be metallized on the flat surface of the inner region 402I of substrate 402 via procedures known to those skilled in the art.

[0100] In embodiments, alignment features in the sensor device 300 and / or substrate 402 are used to align the sensor die with the substrate before and / or during bonding. These alignment features will be discussed below with reference to Figures 14A-15D, 16A, and 16D-16F. In embodiments, the sensor device 300 is bonded to the substrate 402 using one or more metal bonding techniques, as discussed with reference to Figures 15E-G and 16B-16C.

[0101] In some embodiments, the substrate (e.g., substrate 402) may be coupled to the housing (e.g., housing 404) at its outer region (e.g., 402O) to form an hermetically sealed seal. In some embodiments, the housing may be made of stainless steel, a nickel alloy (e.g., Hastelloy® C-276 alloy, an alloy of nickel, molybdenum, and chromium), Kovar (e.g., a nickel-cobalt-iron alloy), or another suitable material. In one embodiment, the housing may be made of stainless steel. In some embodiments, the substrate may be secured to the housing via a metal seal or adhesive (e.g., via welding or brazing) to minimize gas leakage from the processing chamber environment to the external environment. In some embodiments, the substrate may be further secured to the housing via at least one additional leak-proof seal (e.g., an enlarged C-shaped seal). In some embodiments, an O-ring may be further provided between the substrate and the housing to further enhance the hermetically sealed seal between the substrate and the housing and to minimize and / or eliminate vacuum leakage and / or leakage of corrosive gases from the gas passage 240 through the sensor assembly 400. In some embodiments, the cap may be placed between the base plate and the housing to engage (e.g., compress) the O-ring. In some embodiments, the cap may be secured to the housing by one or more fasteners (e.g., bolts, screws, etc.).

[0102] In the embodiment shown in FIG4A, the substrate 402 is further machined to define a conductor pinhole extending over the entire length of the substrate from the top of the outer region 402O through the intermediate region 402M to at least a portion of the inner region 402I. In some embodiments, the substrate 402 further includes a conductor pin 416 within the conductor pinhole, wherein the conductor pin 416 extends over the entire inner region 402O and the intermediate region 402M of the substrate 402 into at least a portion of the inner region 402I of the substrate 402. In some embodiments, the conductor pin 416 is secured to an electrical contact pad 414 disposed on the inner region 402I of the substrate 402 via, for example, a metal seal. The electrical contact 314 on the sensing device, the electrical contact pad 414 on the substrate, and the conductor pin 416, together with one or more external devices (e.g., processing device 230), form a closed circuit during operation. The conductor pin (e.g., 416) extending over the entire substrate may be made of the same conductive material as the electrical contact pad 314 on the sensing device. For example, in one embodiment, the conductor pin 416 is made of platinum.

[0103] Figure 4B illustrates an enlarged view of region A in Figure 4A, where the connection between sensor device 300, substrate 402, electrical contact pad 414, and conductor pin 416 is magnified. In the embodiment shown in Figure 4B, sensor device 300 is coupled to electrical contact pad 414 on an inner region 402I of substrate 402 via its electrical contact 314. In one embodiment, sensor device is coupled to electrical contact pad 414 via a first seal or adhesive 420A (which may be a metal seal or adhesive). As discussed in more detail below, the first metal seal or adhesive may be a platinum-to-platinum adhesive (e.g., a fusion of two platinum contacts) or a metal adhesive comprising multiple metals (e.g., multiple different metal layers), which is created using a multilayer reactive foil (e.g., a nano-laminated foil) having alternating layers of two different metals. In other embodiments, the sensor device is coupled to the electrical contact pad 414 via fused contacts (e.g., by electron beam welding or laser welding) or brazed contacts (e.g., using a brazing alloy). In some embodiments, the sensor device is mounted on the substrate such that the support structure (e.g., 302) of the sensor device (e.g., 300) is vertically oriented relative to the airflow direction (e.g., 242), as will be further explained with reference to FIG. 4C. In some embodiments, the sensor device is mounted on the substrate such that the elongated support structure of the sensor device is parallel to the airflow direction, as will be further explained with reference to at least the sensor assembly shown in FIG. 6D. The targeted orientation of the sensor device 300 relative to the substrate 402 can be achieved by using one or more alignment features, as further described below.

[0104] In one embodiment, the outer region 402O of the substrate 402 is coupled / fixed to the housing 404 via a second seal or adhesive 420B (which may be a metal seal or adhesive), for example, using a second brazing alloy or fusion-welded joint. In some embodiments, the outer region 402O of the substrate 402 may also be fixed to the housing 404 via at least one additional leak-proof seal (e.g., an enlarged C-shaped seal).

[0105] In the embodiment shown in FIG4B, the conductor pin 416 is coupled / fixed to an electrical contact pad 414 on an inner region 402I of the substrate 402. In one embodiment, the conductor pin 416 is fixed to the electrical contact pad 414 via a third seal or adhesive 420C (which may be a metal seal or adhesive), for example, with a third brazing alloy or fusion joint, or with a metal adhesive formed using a multilayer reactive foil (e.g., nano-laminated foil). In some embodiments, the conductor pin 416 may be further fixed to the substrate 402, for example, at an intermediate region 402M, via a fourth seal or adhesive 420D (which may be a metal seal or adhesive), to form an hermetically sealed area to minimize or eliminate vacuum leakage and / or gas (e.g., corrosive gas) from the gas channel 240 through conductor pin holes in the substrate 402 (through which the conductor pin 416 passes).

[0106] Each of the first, second, third, and fourth seals, if present, may independently comprise an Al alloy, Ag alloy, Au alloy, Ni alloy, Si alloy, Au-Ni alloy, Ni-Pd alloy, Ni-Y alloy, Ni-Al alloy, Ti alloy, or a combination thereof. In some embodiments, the brazing alloy, multilayer reactive foil, or welding material used for all seals is the same. In other embodiments, two or more different brazing alloys or metal binder materials may be used for different seals. In one embodiment, at least one of seals 420A, 420B, 420C, or 420D comprises Sn-Ag-Ti as the brazing alloy. It should be understood that the names "first seal," "second seal," "third seal," "fourth seal," etc., should not be construed as binding on the order of assembly of the various components in the sensor assembly described herein, nor should they be construed as binding on the total number of seals in the sensor assembly. Rather, these names are used merely for the convenience of distinguishing one seal from another. Exemplary methods for manufacturing the various sensor components described herein will now be described in more detail with reference to Figures 11A-B and 16A-F.

[0107] In some embodiments, the sensor assembly (e.g., sensor assembly 400) further includes a non-conductive conformal coating on one or more surfaces or on at least a portion of the sensor assembly. The conformal coating may be an anti-corrosion coating. In some embodiments, the coating covers part or all of the sensor device (e.g., 300). In some embodiments, the coating covers part or all of the sensor region 306 and / or interface region 304 of the sensor device 300. In some embodiments, the coating covers part or all of the sensor region 306, including part or all of the sensing element 308. In other embodiments, the conformal coating covers the sensor region 306 but not the sensing element 308. In some embodiments, the coating covers part or all of the substrate 402. In some embodiments, the coating covers the electrodes of the sensor device 300, the electrical contact pads of the substrate 402, and / or the metal bond between the sensor device 300 and / or the substrate 402. In some embodiments, the coating covers part or all of the outer region 402O, the intermediate region 402M, and / or the inner region 402I. In some embodiments, the coating covers part or all of the inner region 402I, including part or all of the electrical contact pads 414. In some embodiments, the coating covers part or all of the intermediate region 402M, including part or all of the conductor pins 416. In some embodiments, the coating covers part or all of the various seals (e.g., first seal 420A, second seal 420B, third seal 420C, and / or fourth seal 420D). In some embodiments, the sensor assembly may remain completely uncoated.

[0108] In some embodiments, the sensor assembly is first assembled to form electrical contacts between all components of the sensor assembly (e.g., between the sensor device and the substrate, and between the substrate and the conductor pins). Thereafter, the assembled sensor assembly is coated such that the coating covers portions of the sensor assembly that are exposed to the airflow when the sensor assembly is coupled into the airflow channel, as discussed below with reference to Figure 4C.

[0109] In some embodiments, the coating is deposited using techniques such as ALD, IAD, low-pressure plasma spraying (LPPS), chemical vapor deposition (CVD), plasma-sprayed chemical vapor deposition (PS-CVD), sputtering, combinations thereof, or other suitable techniques for forming conformal coatings, or modifications thereof. In some embodiments, the coating comprises a ceramic material that is resistant to corrosion by process gases or reactive species. For example, in some embodiments, the coating may include a plasma-resistant ceramic coating comprising rare earth ceramics selected from the following: Y₂O₃, YZrO, YxZryOz, YZrOF, Y₃Al₅O₁₂, Y₄Al₂O₉, YF₃, YxOyFz, YOF, Er₂O₃, Er₃Al₅O₁₂, ErF₃, ExOyFz, ErOF, La₂O₃, Lu₂O₃, Sc₂O₃, ScF₃, ScOF, Gd₂O₃, Sm₂O₃, Dy₂O₃, Y₂O₃-ZrO₂ solid solution, ceramics comprising Y₂Al₄O₉ and Y₂O₃-ZrO₂ solid solutions, or combinations thereof. In some embodiments, the coating comprises Al₂O₃. In one embodiment, the coating comprises Al₂O₃ deposited by atomic layer deposition (ALD). In some embodiments, the coating is substantially uniform in thickness, conformal to the surface of the substrate being coated, non-porous, crack-free, and can act as a diffusion barrier against metallic contaminants, and has high purity (e.g., greater than about 99% purity, or greater than about 99.95% purity). In some embodiments, ALD can be advantageously used to coat all dimensions of the sensor assembly. In some embodiments, the coating is resistant to cracking and / or delamination at a wide range of temperatures (e.g., up to 350°C).

[0110] In some embodiments, the coating may have a uniform thickness, such that when the coating thickness at one location is compared to the coating thickness at another location (or when the coating thickness at one location is compared to the average thickness of the coating, or when the standard deviation of the coating thickness across several locations is evaluated), the thickness variation is less than about + / - 20%, less than about + / - 10%, less than about + / - 5%, or less.

[0111] In some embodiments, the coating may conformally conform to the surface of the underlying substrate, including surface features and / or complex geometries and / or coating portions having a high aspect ratio. For example, the coating may conformally and uniformly coat portions having a high aspect ratio (e.g., length:width (L:W) or length:diameter (L:D), ranging from about 2:1 to about 500:1, about 5:1 to about 300:1, about 10:1 to about 150:1, about 15:1 to about 100:1, or about 20:1 to about 50:1).

[0112] In some embodiments, the coating can be very dense and have very low porosity, for example, less than about 1%, less than about 0.5%, less than about 0.1%, or no porosity (0% porosity). In some embodiments, the coating can have a crack-free microstructure, be hermetically tight, and have high dielectric breakdown resistance.

[0113] In some embodiments, the coating can be deposited at low deposition temperatures (e.g., deposition temperatures up to 350°C), which allows it to be used with a wide variety of materials.

[0114] Figure 4D illustrates a cross-sectional view of a conformal coating formed on the surface of an exemplary sensor assembly according to an embodiment of this disclosure. For simplicity, Figure 4D illustrates a coating 420 on a portion of sensor assembly 400, which may be any portion of sensor assembly 400 described herein. In a similar manner, coating 420 may be deposited on any portion of any other sensor assembly described herein. In some embodiments, the coating comprises a plurality of sequentially deposited layers 422A-422D. In some embodiments, more or fewer layers may be present than shown, and the number of layers may range from 1 to 100 layers, up to 500 layers, or more. For example, multiple atomically thin or near-atomic-thin layers may be deposited, for example, using an ALD. In some embodiments, the composition of each of layers 422A-422D may be alternating. In some embodiments, the total thickness of the coating may range from 10 nanometers to 500 nanometers, any subrange thereof, or any single value thereof. In some embodiments, the coating thickness is optimized to reduce the coating’s impact on measurement sensitivity, while also protecting the sensor assembly (and its various components) from corrosive chemicals that the sensor assembly may be exposed to during processing.

[0115] Figure 4C illustrates a cross-sectional side view of an exemplary flow channel (e.g., flow channel 240) coupled to the sensor assembly 400 of Figure 4A according to an embodiment of this disclosure. As shown in this figure, the sensor assembly 400 can be mounted on a manifold (e.g., a K1S T manifold with a T-fitting 492) via a suitable seal (e.g., a leak-proof seal, such as a C-shaped seal). The manifold can be coupled to the flow channel 240 (e.g., piping) at opposite ends.

[0116] In some embodiments, the housing (e.g., housing 404) may include a gas-facing surface 460 and an opposing surface 470. Housing 404 may have at least one slot (e.g., slot 480B) formed through the housing and shaped to receive a substrate (e.g., substrate 402). Substrate 402 may be inserted into the slot (e.g., slot 480B) such that an interior region 402I of the substrate extends from the gas-facing surface 460, for example, into the interior environment of an airflow channel (e.g., airflow channel 240). In some embodiments, housing 404 may include at least one additional slot (e.g., 480A and 480C) that may be configured to mount housing 404 onto airflow channel 240, for example, via a suitable manifold and / or a suitable seal (e.g., C-shaped seal 490) and / or via a suitable connector (e.g., T-shaped connector 492). Seal 490 may be an airtight seal to prevent gas leakage from airflow channel 240 to the external environment. In some embodiments, the seal 490 is a metal seal, formed, for example, by brazing or welding.

[0117] Figure 5A illustrates a perspective view of a sensor assembly 500 according to an embodiment of this disclosure. In one or more embodiments, the sensor assembly (e.g., sensor assembly 500) includes a substrate (e.g., substrate 502). In some embodiments, the substrate (e.g., substrate 502) includes an outer region (e.g., outer region 502O) optionally used for coupling the substrate to a housing (e.g., housing 504), an inner region (e.g., inner region 502I) for coupling a sensor device (e.g., sensor device 300) to the substrate, and an intermediate region (e.g., intermediate region 502M) positioned between the outer and inner regions (and optionally used for coupling the substrate to the housing). In some embodiments, the dielectric substrate may be a multilayer ceramic made of a plurality of ceramic sheets. The multilayer ceramic substrate may be made of any dielectric ceramic material that can be formed into a suitable shape. In some embodiments, the dielectric multilayer ceramic substrate may be made of alumina (Al₂O₃) or aluminum nitride (AlN). In some embodiments, the substrate may be made of AlN, Si, SiC, Al₂O₃, SiO₂, and the like. Multilayer ceramic substrates are advantageously used due to their high strength, good insulation, low coefficient of thermal expansion, and good chemical stability. Multilayer ceramics can be manufactured by methods known to those skilled in the art, for example by processes including but not limited to one or more of the following operations: tape casting, tape cutting, framing, via punching, via filling, screen printing, lamination, cutting, co-firing, nickel plating, gold plating, or combinations thereof.

[0118] Figure 5C illustrates a perspective view of a multilayer ceramic substrate included in the sensor assembly of Figure 5A, according to an embodiment of this disclosure. Figure 5D illustrates a side view of the multilayer ceramic substrate of Figure 5C. Figure 5E illustrates a top view of the multilayer ceramic substrate of Figure 5C. In the embodiments shown in Figures 5C-5E, two ceramic layers are shown (e.g., a first layer 502A and a second layer 502B covering a portion of the first layer 502A). In the depicted embodiment, ceramic layers 502A and 502B are in contact, thereby achieving a hermetic seal between the layers. In the illustrated embodiment, electrical contact pads 514 are formed / built into the layers of the multilayer ceramic substrate 502 (e.g., electrical contact pads 514 are formed between the first ceramic layer 502A and the second ceramic layer 502B). Electrical contact pads 514 extend from their outer region 502O to their inner region 502I throughout the multilayer ceramic substrate. One advantage of this substrate is that a hermetic seal is achieved between the ceramic layers of the multilayer ceramic and between the electrical contact pads formed between the layers. This hermetic seal reduces the number of fixed locations for various components of the sensor assembly (optionally secured via metal seals, such as brazing or welding) and minimizes potential locations for vacuum and / or gas leakage from the internal environment in the gas channel 240.

[0119] Although substrate 502 is illustrated in Figures 5C-5E as having sharp corners (e.g., a rectangular shape for each layer), this disclosure also contemplates multilayer ceramic substrates with rounded corners, similar to the shape illustrated for substrate 402 in sensor assembly 400. Other substrate shapes may also be used in some embodiments, and this disclosure should not be construed as limited to the shapes shown in the figures.

[0120] In one embodiment, electrical contacts 314 on the interface region of the sensor device 300 may be fixed to electrical contact pads 514 on the inner region 502I of the substrate 502 (e.g., fixed via a metal seal). The electrical contacts 314 on the sensor device, together with the electrical contact pads 514 on the substrate and one or more external devices (e.g., processing device 230), form a closed circuit during operation. The electrical contact pads (e.g., 514) located between the layers of the multilayer ceramic substrate 502 may be made of the same conductive material as the electrical contact pads 314 on the sensor device. For example, in one embodiment, the electrical contact pads 514 are made of platinum.

[0121] In some embodiments, the substrate (e.g., substrate 502) may be coupled to the housing (e.g., housing 504) at its outer region (e.g., 502O) or intermediate region. In some embodiments, the housing may be made of stainless steel, a nickel alloy (e.g., Hastelloy® C-276 alloy, an alloy of nickel, molybdenum, and chromium), Kovar (e.g., a nickel-cobalt-iron alloy), or another suitable material. In one embodiment, the housing may be made of stainless steel. In some embodiments, the substrate may be secured to the housing via a metal seal (e.g., via welding or brazing) to minimize gas leakage from the processing chamber environment to the external environment. In some embodiments, the substrate may be further secured to the housing via at least one additional leak-proof seal (e.g., an enlarged C-type seal).

[0122] In some embodiments, an O-ring 580 may be further provided between the substrate 502 and the housing 504 to further enhance the hermetic seal between the substrate and the housing and to minimize and / or eliminate vacuum leakage and / or leakage of corrosive gases from the gas passage 240 through the sensor assembly 500. In some embodiments, a cap may be placed between the substrate and the housing to engage (e.g., compress) the O-ring. The cap may be tightened onto the housing using screws, bolts, or other fasteners to engage the O-ring.

[0123] Figure 5B illustrates an enlarged view of region B in Figure 5A, where the connection between sensor device 300, substrate 502, and electrical contact pad 514 is magnified. In the embodiment shown in Figure 5B, sensor device 300 is coupled to electrical contact pad 514 on an inner region 502I of substrate 502 via its electrical contacts 314. In one embodiment, sensor device is coupled to electrical contact pad 514 via a first seal or adhesive 520A, which may be a metal seal or adhesive formed by welding, using multilayer reactive foil, fusion, or brazing (e.g., with a first brazing alloy). In some embodiments, sensor device is fixed to substrate such that the support structure (e.g., 302) of sensor device (e.g., 300) is vertically oriented relative to the airflow direction (e.g., 242), as will be further explained with reference to Figure 5F. In some embodiments, sensor device is fixed to substrate such that the elongated support structure of sensor device is parallel to the airflow direction, as will be further explained with reference to at least the sensor assembly shown in Figure 6D. In an embodiment, the orientation and placement of the sensor device 300 relative to the substrate 502 can be controlled using one or more alignment features, as described in more detail below.

[0124] In one embodiment, the outer region 502O of the substrate 502 is coupled / fixed to the housing 504 via a second seal or adhesive 520B (which may be a metal seal or adhesive), for example, using a second brazing alloy, fusion, etc. In some embodiments, the outer region 502O of the substrate 502 may also be fixed to the housing 504 via at least one additional leak-proof seal (e.g., an enlarged C-shaped seal). In some embodiments, the substrate is fixed to the housing via an airtight seal to minimize and / or eliminate leakage of vacuum and / or gas from the gas passage 240.

[0125] Each of the first seal (520A) and the second seal (520B), if present, may independently comprise an Al alloy, Ag alloy, Au alloy, Ni alloy, Si alloy, Au-Ni alloy, Ni-Pd alloy, Ni-Y alloy, Al-Ni alloy, Ti alloy, or a combination thereof. In some embodiments, the alloy or metal used for all seals / adhesives is the same. In other embodiments, two or more different alloys / metals may be used for different seals / adhesives. In one embodiment, at least one of seals 520A or 520B comprises Ag-Cu as a brazing alloy. It should be understood that the terms "first seal," "second seal," etc., should not be construed as binding on the order of assembly of the various components in the sensor assembly described herein, nor should they be construed as binding on the total number of seals in the sensor assembly. Rather, these names are used merely for the convenience of distinguishing one seal from another. Exemplary methods for manufacturing the various sensor assemblies described herein will now be described in more detail with reference to Figures 11A-B and 16A-F.

[0126] In some embodiments, the sensor assembly (e.g., sensor assembly 500) further includes a non-conductive conformal coating on one or more surfaces or on at least a portion of the sensor assembly. The conformal coating may be an anti-corrosion coating. In some embodiments, the coating covers part or all of the sensor device (e.g., 300). In some embodiments, the coating covers part or all of the sensor region 306 and / or interface region 304 of the sensor device 300. In some embodiments, the coating covers part or all of the sensor region 306, including part or all of the sensing element 308. In other embodiments, the conformal coating covers the sensor region 306 but not the sensing element 308. In some embodiments, the coating covers part or all of the substrate 502. In some embodiments, the coating covers part or all of the outer region 502O, the intermediate region 502M, and / or the inner region 502I. In some embodiments, the coating covers part or all of the inner region 502I, including part or all of the electrical contact pads 514. In some embodiments, the coating covers part or all of the intermediate region 502M. In some embodiments, the coating covers part or all of the various seals (e.g., first seal 520A and / or second seal 520B). In some embodiments, the sensor assembly 500 is first assembled to form electrical contacts between all components of the sensor assembly (e.g., between the sensor device and the substrate), and thereafter, the assembled sensor assembly is coated such that the coating covers portions of the sensor assembly exposed to airflow when the sensor assembly is coupled into an airflow channel, as discussed below with reference to FIG. 5F. In some embodiments, the coating deposited on at least a portion of the sensor assembly 500 may be similar to the coatings described above as suitable for coating at least a portion of the sensor assembly 400 (e.g., similar in deposition technique, coating composition / material and / or coating uniformity, conformability, porosity, architecture and the like). In some embodiments, the sensor assembly 500 remains completely uncoated.

[0127] Figure 5F illustrates a cross-sectional side view of an exemplary flow channel (e.g., flow channel 240) coupled to the sensor assembly 500 of Figure 5A, according to an embodiment of this disclosure. As shown in this figure, the sensor assembly 500 can be mounted on a manifold (e.g., a K1S T manifold with a T-fitting 592) via a suitable seal (e.g., a leak-proof seal, such as a C-shaped seal). The manifold can be coupled to the flow channel 240 (e.g., piping) at opposite ends.

[0128] In some embodiments, the housing (e.g., housing 504) may include a gas-facing surface 560 and an opposing surface 570. Housing 504 may have at least one slot (e.g., slot 580B) formed through the housing and shaped to receive a substrate (e.g., substrate 502). Substrate 502 may be inserted into the slot (e.g., slot 580B) such that an internal region 502I of the substrate extends from the gas-facing surface 560, for example, into the internal environment of an airflow channel (e.g., airflow channel 240). In some embodiments, housing 504 may include at least one additional slot (e.g., 580A and 580C) that may be configured to mount housing 504 onto airflow channel 240, for example, via a suitable manifold and / or via a suitable seal (e.g., C-shaped seal 590) and / or via a suitable connector (e.g., T-shaped connector 592). Seal 590 may be an airtight seal to prevent gas leakage from airflow channel 240 to the external environment. In some embodiments, the seal 590 is a metal seal, formed, for example, by brazing or welding.

[0129] While sensor assembly 400 and sensor component 500 illustrate an embodiment where sensor device 300 is fixed to a corresponding substrate such that the support structure of the sensor device is oriented perpendicularly to the airflow direction (e.g., 242), in some embodiments, sensor device 300 may also be fixed to the substrate such that the support structure of the sensor device is oriented parallel to the airflow direction (e.g., 242). This exemplary embodiment will be described with at least reference to sensor assembly 600 in FIG. 6D.

[0130] Figure 6A illustrates a perspective view of a sensor assembly 600 according to an embodiment of this disclosure. In one or more embodiments, the sensor assembly (e.g., sensor assembly 600) includes a substrate (e.g., substrate 602). In some embodiments, the substrate (e.g., substrate 602) includes an outer region (e.g., outer region 602O) optionally used for coupling the substrate to a housing (e.g., housing 604), an inner region (e.g., inner region 602I) for coupling a sensor device (e.g., sensor device 300) to the substrate, and an intermediate region (e.g., intermediate region 602M) positioned between the outer region and the inner region and optionally used for connecting the sensor device to the housing.

[0131] Figure 6C illustrates a perspective view of a substrate (e.g., a substrate included in the sensor assembly 600 of Figure 6A) according to an embodiment of this disclosure. In the embodiment described in Figure 6C, the substrate is made of a dielectric material, such as sapphire or ceramic. In the embodiment described in Figure 6C, the substrate is machined sapphire with rounded edges. The substrate 602 shown has a cylindrical shape in its intermediate region 602M. In the illustrated embodiment, the cylindrical shape of region 602M transitions to a semi-cylindrical shape in the inner region 602I. In the illustrated embodiment, the cylindrical shape of region 602M continues into a portion of the outer region 602O until it reaches the top of the outer region 602O. In the illustrated embodiment, the top of the outer region 602O is shaped as a disk with a diameter larger than the diameter of the cylindrical portions in regions 602O and 602M. The substrate shown further defines conductor pinholes 616H that extend from the top of the outer region 602O of the substrate 602 to the bottom of the inner region 602I of the substrate 602 and are shaped to receive conductor pins 616, as will be described in more detail below. In some embodiments, a substrate with rounded edges (whether sapphire or multilayer ceramic) can alleviate stress, which can extend the operational life of the sensor assembly. The substrate 602 can be machined into the shape shown or any other suitable shape by means known to those skilled in the art.

[0132] In one embodiment, the substrate (e.g., substrate 602) may further include electrical contact pads (e.g., electrical contact pad 614) located at least in an internal region of the substrate. Electrical contacts 314 on the interface region of the sensing device 300 may be secured to the electrical contact pad 614 in the internal region of the substrate (e.g., via a metal seal). The electrical contacts 314 on the sensing device, together with the electrical contact pad 614 on the substrate and one or more external devices (e.g., processing device 230), form a closed circuit during operation. The electrical contact pad (e.g., 614) on the substrate may be made of the same conductive material as the electrical contact pad 314 on the sensing device. For example, in one embodiment, the electrical contact pad 614 is platinum and may be metallized on a substrate (e.g., machined sapphire substrate 602) via procedures known to those skilled in the art.

[0133] In some embodiments, the substrate (e.g., substrate 602) may be coupled to the housing (e.g., housing 604) at its outer region (e.g., 602O) and / or intermediate region 602M. In some embodiments, the housing may be made of stainless steel, a nickel alloy (e.g., Hastelloy® C-276 alloy, an alloy of nickel, molybdenum, and chromium), Kovar (e.g., a nickel-cobalt-iron alloy), or another suitable material. In one embodiment, the housing may be made of stainless steel. In some embodiments, the substrate may be secured to the housing via metal seals or adhesives (e.g., via welding, fusion, or brazing) to minimize gas leakage from the processing chamber environment to the external environment.

[0134] In some embodiments, an O-ring may be further provided between the substrate 602 and the housing 604 to further enhance the hermetic seal between the substrate and the housing and to minimize and / or eliminate vacuum leakage and / or leakage of corrosive gases from the gas passage 240 through the sensor assembly 600. In some embodiments, a cap may be placed between the substrate and the housing to engage (e.g., compress) the O-ring. The cap may be secured by one or more fasteners (e.g., screws, bolts, etc.).

[0135] In the embodiment shown in FIG. 6A, the substrate 602 further includes conductor pins 616 extending over the entire outer region 602O and intermediate region 602M of the substrate 602, down to the bottom of the inner region 602I of the substrate 602. The conductor pins 616 are received in the substrate 602 through conductor pin holes 616H extending from the top of the outer region 602O to the bottom of the inner region 602I of the substrate 602. In some embodiments, the conductor pins 616 are attached to electrical contact pads 614 disposed at the bottom of the inner region 602I of the substrate 602. The electrical contacts 314 on the sensor device, the electrical contact pads 614 on the substrate, and the conductor pins 616, along with one or more external devices (e.g., processing device 230), together form a closed circuit during operation. The conductor pins (e.g., 616) extending over the entire substrate may be made of the same conductive material as the electrical contact pads 314 on the sensor device. For example, in one embodiment, the conductor needle 616 is made of platinum.

[0136] Figure 6B illustrates an enlarged view of region C in Figure 6A, where the connection between sensor device 300 and substrate 602 is magnified. In the embodiment shown in Figure 6B, sensor device 300 is coupled to electrical contact pad 614 on an internal region 602I of substrate 602 via its electrical contacts 314. In one embodiment, sensor device, for example, using metal welding, a first brazing alloy, or a multilayer reactive foil (e.g., nano-laminated foil), is coupled to electrical contact pad 614 via a first seal or adhesive 620A (which may be a metal seal or adhesive). The first seal 620A may include a welded seal (e.g., a welded contact). In some embodiments, sensor device is fixed to substrate such that the support structure (e.g., 302) of sensor device (e.g., 300) is parallel to the airflow direction (e.g., 242), as will be further explained with reference to Figure 6D. One of the main differences between sensor assembly 600 and sensor assembly 400 is the orientation of sensor device 300. In some embodiments, measurements obtained from a sensor assembly having a sensor device fixed in a parallel orientation can be less affected by airflow recirculation and / or turbulence, and can improve conductivity through the flow path. In some embodiments, a sensor device (e.g., sensor device 300) fixed to a substrate in a parallel orientation (relative to the airflow direction, e.g., 242) causes gas recirculation to occur further away from the sensor tip, which has minimal impact on the accuracy of the sensor measurement. In embodiments, one or more alignment features can ensure proper alignment of sensor device 300 with substrate 602.

[0137] In one embodiment, the outer region 602O and / or the middle region 602M of the substrate 602 are coupled / fixed to the housing 604 via a second seal or adhesive 620B (which may be a metal seal or adhesive), for example, using a second brazing alloy, fusion joint, etc., and / or via a third seal or adhesive 620C (which may also be a metal seal or adhesive), for example, using a third brazing alloy, fusion joint, etc. In some embodiments, the outer region 602O of the substrate 602 may be further fixed to the housing 604 via at least one additional seal (e.g., a leak-proof seal (e.g., an enlarged C-shaped seal)).

[0138] In the embodiment shown in FIG. 6B, the conductor needle 616 may be coupled / fixed to the electrical contact pad 614 and / or to the sensor device 300 at the bottom of the inner region 602I of the substrate 602, for example, using a fourth brazing alloy, fusion, etc., via a fourth seal or adhesive 620D (which may be a metal seal or adhesive). In some embodiments, the conductor needle 616 may also be fixed to the substrate 602 (e.g., at the bottom of the inner region 602I) via a fifth seal 620E (which may be a metal seal), for example, using a fifth brazing alloy. In some embodiments, the conductor needle 616 may be fixed to the substrate 602 via a seal to minimize and / or eliminate vacuum leakage and / or leakage of corrosive gases from the gas channel 240 through the sensor assembly 600 (e.g., through the conductor needle hole 616H through which the conductor needle 616 passes).

[0139] Each of the first seal (620A), second seal (620B), third seal (620C), fourth seal (620D), and fifth seal (620E), if present, may independently comprise an Al alloy, Ag alloy, Au alloy, Ni alloy, Si alloy, Au-Ni alloy, Al-Ni alloy, Ni-Pd alloy, Ni-Y alloy, Ti alloy, or a combination thereof. In some embodiments, the brazing alloy or weld used for all seals / adhesives is the same. In other embodiments, two or more different brazing alloys or metal welds may be used for different seals / adhesives. In one embodiment, at least one of seals 620A, 620B, 620C, 620D, or 620E comprises Sn-Ag-Ti as the brazing alloy. It should be understood that the names "first seal," "second seal," "third seal," "fourth seal," and "fifth seal," etc., should not be construed as binding on the order of assembly of the various components in the sensor assembly described herein, nor should they be construed as binding on the total number of seals in the sensor assembly. Rather, these names are used merely for the convenience of distinguishing one seal from another. Exemplary methods for manufacturing the various sensor assemblies described herein will be described in more detail below with reference to Figures 11A-B and 16A-F.

[0140] In some embodiments, the sensor assembly (e.g., sensor assembly 600) further includes a non-conductive conformal coating on one or more surfaces or on at least a portion of the sensor assembly. The conformal coating may be an anti-corrosion coating. In some embodiments, the coating covers part or all of the sensor device (e.g., 300). In some embodiments, the coating covers part or all of the sensor region 306 and / or interface region 304 of the sensor device 300. In some embodiments, the coating covers part or all of the sensor region 306, including part or all of the sensing element 308. In other embodiments, the conformal coating covers the sensor region 306 but not the sensing element 308. In some embodiments, the coating covers part or all of the substrate 602. In some embodiments, the coating covers part or all of the outer region 602O, the intermediate region 602M, and / or the inner region 602I. In some embodiments, the coating covers part or all of the inner region 602I, including part or all of the electrical contact pads 614 and / or conductor pins 616. In some embodiments, the coating covers part or all of the intermediate region 602M. In some embodiments, the coating covers part or all of the various seals (e.g., first seal 620A, second seal 620B, third seal 620C, fourth seal 620D, and / or fifth seal 620E). In some embodiments, the sensor assembly is first assembled to form electrical contacts between all components of the sensor assembly (e.g., between the sensor device, the conductor pin, and the substrate), and then the assembled sensor assembly is coated such that the coating covers at least a portion of the sensor assembly that is exposed to the airflow when the sensor assembly is coupled into the airflow channel, as discussed below with reference to FIG. 6D. In some embodiments, if the coating covers the conductor pin 616 at the top side portion of the outer region 602O of the substrate 602 (e.g., the top side portion is exposed to the external environment and extends from the opposing surface 670 of the housing opposite the gas-facing surface 660), then a portion of the coating can be peeled off (e.g., etched) to expose at least a portion of the conductor pin 616. However, the exposed portion of the conductor needle 616 (in the external environment) can be coupled to one or more external devices (e.g., processing device 230) to form a closed circuit during operation. In some embodiments, the sensor assembly 600 remains completely uncoated.

[0141] In some embodiments, the coating deposited on at least a portion of the sensor assembly 600 may be similar to the coating described above as suitable for coating at least a portion of the sensor assembly 400 (e.g., similar in terms of deposition technique, coating composition / material and / or coating uniformity, conformability, porosity, architecture and the like).

[0142] Figure 6D illustrates a cross-sectional side view of an exemplary flow channel (e.g., flow channel 240) coupled to the sensor assembly 600 of Figure 6A, according to an embodiment of the present disclosure.

[0143] In some embodiments, the housing (e.g., housing 604) may include a gas-facing surface 660 and an opposing surface 670 opposite the gas-facing surface. Housing 604 may have at least one slot (e.g., slot 680B) formed through the housing and shaped to receive a substrate (e.g., substrate 602). Substrate 602 may be inserted into the slot (e.g., slot 680B) such that an internal region 602I of the substrate extends from the gas-facing surface 660, for example, into the internal environment of an airflow channel (e.g., airflow channel 240). In some embodiments, housing 604 may include at least one additional slot (e.g., 680A and 680C) that may be configured to mount housing 604 onto the airflow channel 240, for example, via a suitable manifold (e.g., K1H manifold) and / or via a suitable seal (e.g., C-shaped seal 690) and / or via a suitable connector. Seal 690 may be an airtight seal to prevent gas leakage from the airflow channel 240. In some embodiments, the seal 690 is a metal seal, formed, for example, by brazing or welding.

[0144] In some embodiments, the sensor assembly 600 is larger than the sensor assemblies 400 and 500 because the substrate 602 is inserted into the slot 680B when the sensor device 300 is fixed to the substrate 602 in a parallel orientation relative to the airflow 242 (rather than a vertical orientation as shown in the sensor assemblies 400 and 500). In some embodiments, the slot 680B may be shaped to accommodate the insertion of the substrate 602 with the sensor device 300 coupled to it in a parallel orientation, and the sensing element 308 does not contact the periphery of the slot 680B.

[0145] Figure 7A illustrates a perspective view of sensor assembly 700 according to certain other embodiments of this disclosure. In one or more embodiments, the sensor assembly (e.g., sensor assembly 700) includes a substrate (e.g., substrate 702). In some embodiments, the substrate (e.g., substrate 702) includes an outer region (e.g., outer region 702O), an inner region (e.g., inner region 702I) for coupling a sensor device (e.g., sensor device 300) to the substrate, and an intermediate region (e.g., intermediate region 702M) positioned between the outer region and the inner region. In some embodiments, the substrate may be coupled to a housing (e.g., housing 704) at the intermediate region 702M and / or the outer region 702O. In some embodiments, substrate 702 may be a multilayer ceramic made of a plurality of ceramic sheets, similar to the multilayer ceramic substrate 502 described with respect to sensor assembly 500.

[0146] Figure 7B illustrates a perspective view of a multilayer ceramic substrate included in the sensor assembly of Figure 7A according to an embodiment of this disclosure, with sensor device 300 coupled to substrate 702 at an inner region 702I. Figure 7C illustrates a side view of the multilayer ceramic substrate of Figure 7B. Figure 7D illustrates a top view of the multilayer ceramic substrate of Figure 7B. In the embodiments shown in Figures 7B-7D, two ceramic layers are shown (e.g., a first layer 702A and a second layer 702B covering a portion of the first layer 702A at an intermediate region 702M). In the depicted embodiment, ceramic layers 702A and 702B are in contact, such that a hermetic seal is achieved between the layers (similar to multilayer ceramic substrate 502). In the illustrated embodiment, electrical contact pads 714 are formed / built into the layers of the multilayer ceramic substrate 702 (e.g., electrical contact pads 714 are formed between the first ceramic layer 702A and the second ceramic layer 702B). Electrical contact pads 714 extend from their outer region 702O to their inner region 702I throughout the multilayer ceramic substrate. The advantage of this type of substrate (such as substrate 502) is that it achieves a hermetic seal between the ceramic layers of the multilayer ceramic substrate and between the electrical contact pads formed between the layers. This hermetic seal reduces the number of locations where various components of the sensor assembly are fixed by metal seals (e.g., via brazing or fusion).

[0147] The ceramic substrate 702 can be made of any suitable plasma-resistant ceramic, and it can be shaped into a suitable multilayer ceramic according to methods known to those skilled in the art, as explained above regarding substrate 502. Similarly, the ceramic substrate 702 can be made of a material similar to the material described above for substrate 502.

[0148] In one embodiment, electrical contacts 314 on the interface region of the sensor device 300 may be fixed to electrical contact pads 714 on the inner region of the substrate 702 (e.g., via a metal seal). The electrical contacts 314 on the sensor device, together with the electrical contact pads 714 on the substrate and one or more external devices (e.g., processing device 230), form a closed circuit during operation. The electrical contact pads (e.g., 714) located between the layers of the multilayer ceramic substrate 702 may be made of the same conductive material as the electrical contact pads 314 on the sensor device. For example, in one embodiment, the electrical contact pads 714 are made of platinum.

[0149] In some embodiments, a substrate (e.g., substrate 702) may be coupled to a housing (e.g., housing 704) at an intermediate region (e.g., 702M). In some embodiments, the housing may be made of stainless steel, a nickel alloy (e.g., Hastelloy® C-276 alloy, an alloy of nickel, molybdenum, and chromium), Kovar (e.g., a nickel-cobalt-iron alloy), or another suitable material. In one embodiment, the housing may be made of stainless steel. In some embodiments, the substrate may be secured to the housing via a metal seal or adhesive (e.g., via brazing, laser welding, electron beam welding, etc.) to minimize gas leakage from the processing chamber environment to the external environment. In some embodiments, an O-ring may be disposed between substrate 702 and housing 704. In some embodiments, a cap configured to engage (e.g., compress) the O-ring may be disposed between substrate 702 and housing 704. The cap may be secured by one or more fasteners (e.g., one or more bolts, screws, etc.).

[0150] In one embodiment, the sensor device 300 is coupled to an electrical contact pad 714 on an internal region 702I of the substrate 702 via its electrical contacts 314. In one embodiment, the sensor device is coupled to the electrical contact pad 714 via a first seal or adhesive 720A, which may be a metal seal or adhesive formed by welding, using multilayer reactive foil, fusion, or brazing (e.g., with a first brazing alloy). In some embodiments, the first seal / adhesive 720A is formed by a welding operation (e.g., electron beam welding, laser beam welding, etc.). In some embodiments, the sensor device is fixed to the substrate such that the support structure (e.g., 302) of the sensor device (e.g., 300) is parallel to the airflow direction (e.g., 242). In some embodiments, the sensor device may be fixed to the substrate 702 such that the support structure of the sensor device is perpendicular to the airflow direction (not shown). One or more alignment features may provide accurate positioning and / or alignment of the sensor device 300 relative to the substrate 702.

[0151] In one embodiment, the intermediate region 702M of the substrate 702 is coupled / fixed to the housing 704 via a second seal or adhesive 720B (which may be a metal seal or adhesive), for example, using a second brazing alloy, metal welding, etc. In some embodiments, the substrate 702 may be fixed to the housing 704 via an airtight seal to minimize leakage of vacuum and / or gas from the processing chamber environment and / or from the gas passage 240 to the external environment.

[0152] Each of the first seal / adhesive (720A) and the second seal / adhesive (720B), if present, may independently comprise an Al alloy, Ag alloy, Au alloy, Ni alloy, Si alloy, Au-Ni alloy, Ni-Pd alloy, Ni-Y alloy, Ni-Al alloy, Ti alloy, or a combination thereof. In some embodiments, the brazing alloy or metal adhesive used for all seals is the same. In other embodiments, two or more different brazing alloys or metals may be used for different seals / adhesives. In one embodiment, at least one of the seals / adhesives 720A or 720B comprises Ag-Cu as the brazing alloy. It should be understood that the names "first seal," "second seal," etc., should not be construed as binding on the order of assembly of the various components in the sensor assembly described herein, nor should they be construed as binding on the total number of seals in the sensor assembly. Rather, these names are used merely for the convenience of distinguishing one seal from another. Exemplary methods for manufacturing the various sensor components described herein will now be described in more detail with reference to Figures 11A-B and 16A-F.

[0153] In some embodiments, the sensor assembly (e.g., sensor assembly 700) further includes a non-conductive conformal coating on one or more surfaces or on at least a portion of the sensor assembly. The conformal coating may be an anti-corrosion coating. In some embodiments, the coating covers part or all of the sensor device (e.g., 300). In some embodiments, the coating covers part or all of the sensor region 306 and / or interface region 304 of the sensor device 300. In some embodiments, the coating covers part or all of the sensor region 306, including part or all of the sensing element 308. In other embodiments, the conformal coating covers the sensor region 306 but not the sensing element 308. In some embodiments, the coating covers part or all of the substrate 702. In some embodiments, the coating covers part or all of the outer region 702O, the intermediate region 702M, and / or the inner region 702I. In some embodiments, the coating covers part or all of the inner region 702I, including part or all of the electrical contact pads 714. In some embodiments, the coating covers part or all of the intermediate region 702M. In some embodiments, the coating covers part or all of the various seals (e.g., first seal 720A and / or second seal 720B). In some embodiments, the sensor assembly 700 is first assembled to form electrical contacts between all components of the sensor assembly (e.g., between the sensor device and the substrate), and thereafter, the assembled sensor assembly is coated such that the coating covers portions of the sensor assembly exposed to airflow when the sensor assembly is coupled into an airflow channel. In some embodiments, the coating deposited on at least a portion of the sensor assembly 700 may be similar to the coatings described above as suitable for coating at least a portion of the sensor assembly 700 (e.g., similar in deposition technique, coating composition / material and / or coating uniformity, conformability, porosity, architecture and the like). In some embodiments, the sensor assembly 700 remains completely uncoated.

[0154] Figure 7E illustrates a front view of section AA in Figure 7A. In some embodiments, the housing (e.g., housing 704) may include a gas-facing surface 760 and an opposing surface 770 opposite to the gas-facing surface. Housing 704 may be shaped as an airflow channel, similar to airflow channel 240. The diameter or width and / or height of the housing (if the housing shape is not cylindrical / tube) may be larger than the diameter of the airflow channel (e.g., 240). The larger diameter or width and / or height of housing 704 may be configured to provide space for sensor components without restricting airflow, such that it has minimal (or substantially no) impact on the airflow parameters being measured by the sensor device.

[0155] The housing 704 may have at least one slot (e.g., slot 780A) formed through the housing and shaped to receive a substrate (e.g., substrate 702). The substrate 702 may be inserted into the slot (e.g., slot 780A) such that an inner region 702I of the substrate extends from the gas-facing surface 760, for example, into the interior environment of an airflow channel (e.g., airflow channel 240). In some embodiments, the substrate 702 may be inserted into the slot 780A and cantilevered to the housing 704 at a middle region 702M of the substrate 702, such that the inner region 702I of the substrate extends from the gas-facing surface 760 into the interior environment of the airflow channel, and the outer region 702O of the substrate extends from the opposing surface 770 into the outer region, as shown in the front view of section AA in FIG7E.

[0156] In some embodiments, as illustrated in Figures 8A and 8B, the housing 704 has a first slot 780A formed at a first end 765A (which, for example, extends from the gas-facing surface 760 to an opposing surface 770 opposite the gas-facing surface) and a second slot 780B formed at an opposing second end 765B (which, for example, extends from the gas-facing surface 760 to an opposing surface 770 opposite the gas-facing surface). This housing can accommodate a substrate 802, which can be similar to substrate 702. In some embodiments, substrate 802 is a multilayer ceramic substrate. An advantage of substrate 802 (like substrates 502 and 702) is that a hermetically sealed interface is achieved between the ceramic layers of the multilayer ceramic substrate and between the electrical contact pads formed between the layers. This hermetically sealed interface reduces the number of locations where various components of the sensor assembly are secured by metal seals (e.g., via brazing or fusion).

[0157] The ceramic substrate 802 can be made of any suitable plasma-resistant ceramic, and it can be shaped into a suitable multilayer ceramic according to methods known to those skilled in the art, as explained above regarding substrate 502. Similarly, the ceramic substrate 802 can be made of a material similar to the material described above for substrate 502.

[0158] The multilayer ceramic substrate 802 may include a first end 802A and a second end 802B opposite to the first end. The first end 802A of the substrate 802 may include a first outer region 802O1, an inner region 802I, and a first intermediate region 802M1 positioned between the first outer region 802O1 and the inner region 802I. The second end 802B of the substrate 802 may include a second outer region 802O2, the same inner region 802I, and a second intermediate region 802M2 positioned between the second outer region 802O2 and the inner region 802I. The multilayer ceramic substrate 802 may include electrical contact pads 814 formed between the layers of the multilayer ceramic substrate 802. The electrical contact pads 814 may extend from the first end 802A to the second opposite end 802B throughout the multilayer ceramic substrate 802, as shown in the front view of cross-section BB in FIG8B.

[0159] A multilayer ceramic substrate 802 can be fixed to the housing 704 at a first intermediate region 802M1 and a second intermediate region 802M2. In some embodiments, the multilayer ceramic substrate can be inserted into the housing 704 via a first slot 780A that extends across the entire diameter (or width) of the housing 704 to a second slot 780B. A first end 802A of the multilayer ceramic substrate 802 can be disposed via the first slot 780A, and a second opposing end 802B of the multilayer ceramic substrate 802 can be disposed via the second opposing slot 780B. In this configuration, a first outer region 802O1 of the substrate 802 can extend from the opposing surface 770 of the housing 704 at the first end 765A to the outer region of the first end. Furthermore, in this configuration, a second outer region 802O2 of the substrate 802 can extend from the opposing surface 770 of the housing 704 at the second opposing end 765B to the outer region of the second opposing end. Furthermore, in this configuration, the internal region 802I of the substrate 802 can extend from the gas-facing surface 760 of the housing 704 at the first end 765A to the gas-facing surface 760 of the housing 704 at the second end 765B. In some embodiments, the substrate 802 can be fixed to the housing via a metal seal (e.g., via brazing) to form an hermetically tight seal, thereby minimizing gas leakage from the processing chamber environment to the external environment. The seal between the housing 704 and the substrate 802 (or between the housing 704 and the substrate 702) can be an hermetically tight seal to prevent gas leakage and / or vacuum leakage from the gas flow channel 240. In some embodiments, the seal is a metal seal formed by brazing or welding, for example, using any of the brazing alloys described above. Various sealing configurations can be used appropriately, as will be described and explained in more detail with reference to Figures 9A-9C and 10A-10D.

[0160] In the embodiments shown in Figures 8A-8B, the sensor device 300 can be coupled / fixed to the substrate 802 at an internal region 802I. As described previously for the sensor assembly, the sensor device 300 can be fixed to the substrate via a metal seal / adhesive between electrical contacts 314 (on the sensor device 300) and electrical contact pads 814 on the substrate 802. The metal seal / adhesive can be formed by brazing, soldering, fusion (e.g., laser welding or electron beam welding), using multilayer reactive foil, etc. The electrical contacts 314 on the sensor device, together with the electrical contact pads 814 on the substrate and one or more external devices (e.g., processing device 230), form a closed circuit during operation. The electrical contact pads (e.g., 814) located between the layers of the multilayer ceramic substrate 802 can be made of the same conductive material as the electrical contact pads 314 on the sensor device. For example, in one embodiment, the electrical contact pads 814 are made of platinum.

[0161] The sensor device 300 can be fixed to the substrate 802 such that the support structure (e.g., 302) is parallel to the airflow direction (e.g., 242). In some embodiments, the sensor device can be fixed to the substrate 802 such that the support structure of the sensor device is perpendicular to the airflow direction (not shown).

[0162] In some embodiments, the sensor assembly shown in Figures 8A-8B further includes a non-conductive conformal coating on one or more surfaces or on at least a portion of the sensor assembly. The conformal coating may be an anti-corrosion coating. In some embodiments, the coating covers part or all of the sensor device (e.g., 300). In some embodiments, the coating covers part or all of the sensor region 306 and / or interface region 304 of the sensor device 300. In some embodiments, the coating covers part or all of the sensor region 306, including part or all of the sensing element 308. In other embodiments, the conformal coating covers the sensor region 306 but not the sensing element 308. In some embodiments, the coating covers part or all of the substrate 802. In some embodiments, the coating covers part or all of the outer regions 802O1 and 802O2, the intermediate regions 802M1 and 802M2, and / or the inner region 802I. In some embodiments, the coating covers part or all of the inner region 802I, including part or all of the electrical contact pads 814. In some embodiments, the coating covers part or all of various seals (e.g., a first seal 820A between the sensor device 300 and the substrate 802, and / or a second seal 820B between a first intermediate region 802M1 of the substrate 802 and a first end 765A of the housing 704, and / or a third seal 820C between a second intermediate region 802M2 of the substrate 802 and a second end 765B of the housing 704). In some embodiments, the sensor assembly 800 is first assembled to form electrical contacts between all components of the sensor assembly (e.g., between the sensor device and the substrate), and thereafter, the assembled sensor assembly is coated such that the coating covers portions of the sensor assembly exposed to airflow when the sensor assembly is coupled into an airflow channel. In some embodiments, the coating deposited on at least a portion of the sensor assembly 800 may be similar to the coating described above as suitable for coating at least a portion of the sensor assembly 400 (e.g., similar in deposition technique, coating composition / material and / or coating uniformity, conformability, porosity, architecture and the like). In some embodiments, the sensor assembly 800 remains completely uncoated.

[0163] It should be understood that the terms "first seal," "second seal," "third seal," etc., should not be construed as binding on the order of assembly of the various components in the sensor assembly described herein, nor should they be construed as binding on the total number of seals in the sensor assembly. Rather, these names are used merely for the convenience of distinguishing one seal from another. Exemplary methods for manufacturing the various sensor assemblies described herein will now be described in more detail with reference to Figures 11A-B and 16A-F.

[0164] As previously described, the substrate (e.g., 702 or 802) can be bonded to the housing (e.g., 704) at the intersection between the periphery of the slot through the housing (e.g., the periphery of slot 780A or slot 780B) and the periphery of the central region of the substrate (e.g., 702M, 802M1, or 802M2). However, in some embodiments, the central region of the substrate and the slot through the housing can also be shaped to allow face-to-face bonding between the two. It is believed, without being construed as limiting, that face-to-face bonding between the substrate (e.g., at the central region) and the housing can reduce stress that may occur during bonding. Such exemplary face-to-face bonding is illustrated in Figures 9A-9C and 10A-10D.

[0165] Figure 9A illustrates a perspective view of a sensor assembly 900 according to an embodiment of the present disclosure. As can be seen from Figure 9A, the sensor assembly 900 may include a housing 904, which may be similar to a housing 704. The housing 904 may also have a gas-facing surface 960 and an opposing surface 970 opposite to the gas-facing surface. The housing 904 may also have a slot 980A therethrough. In some embodiments, the housing 904 may include a tapered region at the periphery of the slot 980A, the tapered region being configured to establish a flat surface at the periphery of the slot 980A, and a central region 902M of the substrate 902 may be bonded to the tapered region in a parallel orientation.

[0166] Figure 9B illustrates a perspective view of a multilayer ceramic substrate 902, with a sensor device 300 coupled to an internal region. Like other multilayer ceramic substrates described above, the multilayer ceramic substrate 902 can be fabricated using methods known to those skilled in the art. The multilayer ceramic substrate 902 may have an internal region 902I, an external region 902O, and an intermediate region 902M positioned between the internal region 902I and the external region 902O, on which the sensor device 300 can be fixed. In some embodiments, the thickness and / or length of the intermediate region 902M is greater than that of the internal region 902I and / or the external region 902O. In some embodiments, the intermediate region 902M has a first surface 902M1 and a second surface 902M2 opposite to the first surface. When the substrate 902 is fixed to a housing 904, the first surface 902M1 may be adjacent to the opposing surface 970 of the housing 904 and may be bonded face-to-face.

[0167] In some embodiments, the shape of the substrate 902 is formed using multiple ceramic layers by methods known to those skilled in the art. In some embodiments, a hermetic seal is achieved between the layers of the multilayer ceramic substrate. In some embodiments, electrical contact pads 914 are formed / built into the layers of the multilayer ceramic substrate 902 (extending from the outer region 902O to the inner region 902I across the entire substrate 902), maintaining a hermetic seal even with the presence of electrical contact pads 914 between the layers.

[0168] The ceramic substrate 902 can be made of any suitable plasma-resistant ceramic, and it can be shaped into a suitable multilayer ceramic according to methods known to those skilled in the art, as explained above with respect to substrate 502. Similarly, the ceramic substrate 902 can be made of a material similar to the material described above with respect to substrate 502.

[0169] At least a portion or all of the sensor assembly 900 may be coated with a protective coating, as described above for other sensor assemblies. The coating deposited on at least a portion of the sensor assembly 900 may be similar to the coatings described above suitable for coating at least a portion of the sensor assembly 400 (e.g., similar in deposition technique, coating composition / material, and / or coating uniformity, conformability, porosity, architecture, corrosion resistance, and the like). In some embodiments, the sensor assembly 900 may remain completely uncoated.

[0170] Figure 9C illustrates a front view of the cross section CC in Figure 9A. As shown in Figure 9C, the sensor assembly 900 is similar to the sensor assembly 700, except for the bonding between the substrate 902 and the housing 904. In the sensor assembly 900, a multilayer ceramic substrate 902, on which the sensor device 300 is fixed in a parallel orientation (relative to the airflow 242) (at the inner region 902I), is cantilevered and inserted into the slot 980A (shown in Figure 9C) until the first surface 902M1 of the middle region 902M of the substrate contacts (face-to-face) the tapered periphery of the slot 980A (located on the opposite surface 970 of the housing 904). The substrate assembly 902 can then be fixed to the housing 904, for example via a metal seal (e.g., a brazing alloy), to form an hermetically sealed seal to minimize leakage of gas and / or vacuum from the gas passage 240 to the external environment.

[0171] Although not shown in the figures, the sensor assembly 900 can also be modified such that the substrate extends from one end of the housing to the other, similar to the sensor assembly 800. With this modification, each end of the modified substrate can be fixed to each corresponding end of the housing via face-to-face bonding, similar to the bonding described for the sensor assembly 900.

[0172] Figure 10A illustrates a perspective view of a sensor assembly 1000 according to an embodiment of the present disclosure. As can be seen from Figure 10A, the sensor assembly 1000 may include a housing 1004, which may be similar to housings 704 and 904. Housing 1004 may also have a gas-facing surface 1060 and an opposing surface 1070 opposite to the gas-facing surface. Housing 1004 may also have a slot 1080A therethrough. In some embodiments, housing 1004 may include a tapered region at the periphery of slot 1080A, the tapered region being configured to establish a flat surface at the periphery of slot 1080A, to which a central region 1002M of substrate 1002 may be bonded in a parallel orientation. Alternatively, as shown in Figure 10A, housing 1004 may have a region 1004M with flat sidewalls of square or rectangular shape, to which the central region 1002 of substrate 1002 may be bonded in a parallel face-to-face orientation. In some embodiments, housing 1004 may have tubular gas channels 1004C extending from two opposite sides of region 1004M having square or rectangular flat sidewalls.

[0173] Figure 10B illustrates a perspective view of the multilayer ceramic substrate 1002. Like other multilayer ceramic substrates described above, the multilayer ceramic substrate 1002 can be fabricated using methods known to those skilled in the art. The multilayer ceramic substrate 1002 may have an inner region 1002I, an outer region 1002O, and an intermediate region 1002M positioned between the inner region 1002I and the outer region 1002O, on which the sensor device 300 can be fixed. In some embodiments, the thickness and / or length of the intermediate region 1002M is greater than that of the inner region 1002I and / or the outer region 1002O. In some embodiments, the intermediate region 1002M is shaped as a disk with rounded edges (e.g., oval or circular) and has a first surface 1002M1 and a second surface 1002M2 opposite to the first surface. When the substrate 1002 is fixed to the housing 1004, the first surface 1002M1 may be adjacent to the opposing surface 1070 of the housing 1004 and may be bonded face-to-face.

[0174] In some embodiments, the substrate 1002 is shaped using a plurality of ceramic layers by methods known to those skilled in the art. In some embodiments, a hermetic seal is achieved between the layers of the multilayer ceramic substrate. In some embodiments, electrical contact pads 1014 are formed / built into the layers of the multilayer ceramic substrate 1002 (extending from the outer region 1002O to the inner region 1002I across the entire substrate 1002), maintaining a hermetic seal even with the presence of electrical contact pads 1014 between the layers.

[0175] The ceramic substrate 1002 can be made of any suitable plasma-resistant ceramic, and it can be shaped into a suitable multilayer ceramic according to methods known to those skilled in the art, as explained above with respect to substrate 502. Similarly, the ceramic substrate 1002 can be made of a material similar to the material described above with respect to substrate 502.

[0176] In some embodiments, the sensor assembly 1000 further includes a connector / flange 1300. The connector / flange 1300 may be shaped as a flat plate having a ring defined through its central region, the ring being configured to surround a portion of the ceramic substrate 1002. The connector / flange 1300 may have a first side 1300S1 (e.g., a side facing the housing) and a second side 1300S2 opposite the first side (e.g., a side facing the substrate). The connector / flange 1300 may have a rounded periphery (e.g., an oval or circular periphery, or a rectangular shape with arcuate edges). The connector / flange 1300 may adhere to the housing 1004 (e.g., the opposing surface 1070 of the housing 1004) near, for example, a location of slot 1080A (e.g., around the periphery of slot 1080A). For example, the flange / mate 1300 may be fused (e.g., via electron beam welding) to the housing 1004 such that a first side 1300S1 of the mate / flange 1300 is adjacent to the housing 1004 (e.g., the opposing surface 1070 of the housing 1004), as shown, for example, by the numeral 1300D in FIG. 10D. In some embodiments, the flange / mate 1300 may be brazed, fused, or welded to the housing 1004. The mate / flange 1300 may be fixed to the housing 1004 in a parallel, face-to-face configuration.

[0177] The connector / flange 1300 may be made of a material whose coefficient of thermal expansion is between that of the multilayer ceramic substrate 1002 and the housing 1004. In some embodiments, the housing 1004 has a first coefficient of thermal expansion (CTE1), the substrate 1002 has a second coefficient of thermal expansion (CTE2), and the connector / flange 1300 has a third coefficient of thermal expansion (CTE3). In some embodiments, the value of CTE3 is between CTE1 and CTE2. For example, the housing 1004 may be made of stainless steel having a CTE1, the dielectric multilayer ceramic substrate may be made of ceramic having a CTE2, and the connector / flange 1300 may be made of Kova alloy (a nickel-cobalt-iron alloy) having a CTE3 between CTE1 and CTE2. In some embodiments, the connector / flange 1300 comprises stainless steel, a nickel alloy, a nickel-chromium-molybdenum alloy, a nickel-cobalt-iron alloy, or a combination thereof. In some embodiments, the substrate 1002 is fixed to the connector / flange 1300 such that the first surface 1002M1 can be adjacent to the second side 1300S2 of the connector / flange 1300 and can be bonded thereto in a face-to-face configuration.

[0178] The substrate 1002 can be secured to the connector / flange 1300 (if present) via a first metal seal 1300A (e.g., by welding or brazing with any metal alloy described above or any other suitable metal alloy) or to the housing 1004 (if the connector / flange 1300 is absent). In one embodiment, the substrate 1002 can be secured to the connector / flange 1300 with an Al alloy via brazing.

[0179] In some embodiments, a backup ring 1500 may be further disposed around a portion of the substrate 1002 between the flange 1300 and the housing 1004. The backup ring may be shaped as a flat plate having a ring defined in its central region, configured to surround a portion of the ceramic substrate 1002. The backup ring may include a housing-facing side and a substrate-facing side opposite the housing-facing side. In some embodiments, the substrate-facing side of the backup ring may be secured to the housing-facing side of the flange / mate 1300 via a second metal seal 1300B. The second metal seal 1300B may be a brazed seal or fusion formed of any metal alloy described above or any other suitable metal alloy. In some embodiments, the ceramic backup ring 1500 is configured to reduce stress at the joints (e.g., the joint between the flange / mate 1300 and the housing 1004). The backup ring 1500 may be configured to reduce thermal stress at the joints during joint formation. The support ring 1500 can be secured to the flange / attachment 1300 and / or housing 1004 via a parallel face-to-face configuration.

[0180] The support ring 1500 may be made of a material whose coefficient of thermal expansion is between that of the multilayer ceramic substrate 1002 and the housing 1004. In some embodiments, the support ring 1500 is made of a ceramic material. In some embodiments, the support ring 1500 may be made of the same material as the substrate 1002 and / or the housing 1004.

[0181] In some embodiments, after the support ring 1500 and the connector / flange 1300 are secured to the substrate 1002, a sensor device (e.g., sensor device 300) can be secured to an internal region of the substrate 1002 via a third seal 1300C. Subsequently, the substrate 1002 with the support ring 1500, connector / flange 1300, and sensor device 300 can be inserted into the housing 1004, and the connector / flange 1300 can be secured (e.g., via electron beam welding) to the housing 1004 to form a hermetically sealed environment, minimizing vacuum and / or gas leakage from the gas passage 240 to the external environment.

[0182] Each of the first seal 1300A, the second seal 1300B, the third seal 1300C, and the optional fourth seal 1300D (if not fused), if present, may independently comprise an Al alloy, an Ag alloy, an Au alloy, a Ni alloy, a Si alloy, an Au-Ni alloy, a Ni-Pd alloy, a Ni-Y alloy, a Ti alloy, or a combination thereof. In some embodiments, the brazing alloy used for all seals is the same. In other embodiments, two or more different brazing alloys may be used for different seals. It should be understood that the names "first seal," "second seal," "third seal," "fourth seal," etc., should not be construed as binding on the order of assembly of the various components in the sensor assembly described herein, nor should they be construed as binding on the total number of seals in the sensor assembly. Rather, these names are used merely for the convenience of distinguishing one seal from another. Exemplary methods for manufacturing the various sensor assemblies described herein will now be described in more detail with reference to Figures 11A-B and 16A-F.

[0183] At least a portion or all of the sensor assembly 1000 may be coated with a protective coating, as described above for other sensor assemblies. The coating deposited on at least a portion of the sensor assembly 1000 may be similar to the coatings described above suitable for coating at least a portion of the sensor assembly 400 (e.g., similar in deposition technique, coating composition / material, and / or coating uniformity, conformability, porosity, architecture, corrosion resistance, and the like). In some embodiments, the sensor assembly 1000 may be completely uncoated.

[0184] Figure 10C illustrates a front view of the cross section CC of Figure 10A. As shown in Figure 10C, the sensor assembly 1000 is similar to sensor assemblies 700 and 900, except for the bonding between the substrate 1002 and the housing 1004. In the sensor assembly 1000, a multilayer ceramic substrate 1002, on which the sensor device 300 is fixed in a parallel orientation (relative to the airflow 242) (at the inner region 1002I), is cantilevered and inserted into the slot 1080A (shown in Figure 10F) until the first surface 1002M1 of the middle region 1002M of the substrate contacts (face-to-face) either the tapered periphery (not shown) of the slot 1080A or the second side 1300S2 of the connector / flange 1300 (which may be located on the opposite surface 1070 of the housing 1004). Then, the substrate assembly 1002 can be secured to the connector / flange 1300, for example, via a metal seal (e.g., with brazing alloy or fusion joint).

[0185] Although not shown in the diagram, the sensor assembly 1000 can also be modified such that the substrate extends from one end of the housing to the other end, similar to the sensor assembly 800. With this modification, each end of the modified substrate can be fixed to each corresponding end of the housing by means of a central connector / flange, via face-to-face bonding similar to the bonding described for the sensor assembly 1000.

[0186] Figure 11A illustrates a method 1100 for adapting a sensor device for use in a flow control apparatus according to an embodiment of this disclosure. At block 1110, a substrate is provided. The substrate may have an outer region, an inner region, and an intermediate region positioned between the outer and inner regions, and may further have electrical contact pads located at least in its inner region. Such exemplary substrates are shown in sensor assemblies described above, such as substrates 402, 502, 602, 702, 802, 902, and 1002. In some embodiments, the substrate may be machined into the shape described above or any other suitable shape before being provided. In some embodiments, the electrical contact pads may be metallized into the inner region of the substrate. In some embodiments, the substrate may be formed as a multilayer ceramic substrate having any of the shapes described above (or any other suitable shape) before being provided, and electrical contact pads are formed between the layers of the multilayer ceramic substrate such that the electrical contact pads extend from the outer region to the inner region throughout the multilayer ceramic substrate.

[0187] At block 1120, a sensing device (e.g., sensing device 300 as described in FIG. 3 or any other suitable sensing device) may be coupled to the substrate at an internal region of the substrate. The sensing device may be coupled to the substrate according to embodiments described below with reference to FIG. 15A-G and 16A-F. In some embodiments, the sensing device includes a support structure comprising an interface region (e.g., interface region 304) at one end of the sensing device and a sensing region (e.g., sensing region 306) at the other end of the sensing device. The sensing region may include a self-standing sensing element (e.g., sensing element 308) suspended at the sensing region. The sensing device may further include electrical contacts (e.g., electrical contacts 314) extending from the sensing element to the top of the interface region along the entire length of the elongated support structure. The sensing device may be secured / coupled to the substrate such that the electrical contacts on the sensing device contact electrical contact pads on the substrate to establish a continuous and closed circuit for transmitting signals from the sensing device to a processing device (e.g., processing device 230).

[0188] In some embodiments, the sensor device may be secured to the substrate by forming a first seal / adhesive between an electrical contact pad (e.g., 414, 514, 614, 714, 814, 914, or 1014) on the substrate and an electrical contact on the sensor device (e.g., 314). Examples of securing the sensor device to the substrate by forming a first seal / adhesive are illustrated with reference to Figures 15A-G and 16B-F. In some embodiments, the sensor device in any sensor assembly considered herein may be secured to the substrate via brazing, soldering, using multilayer reactive foil, or fusion (or any other chemical mode for attaching the sensor device to the substrate). In some embodiments, the sensor device in any sensor assembly considered herein may be secured to the substrate via a heat source (e.g., laser fusion, electron beam fusion, etc.). In embodiments, the sensor device and / or substrate are substantially transparent to the radiation wavelength used by the electron beam fusion or laser fusion. Therefore, radiation (e.g., light) from the welder can pass through the sensor device or the substrate to heat the interface between the sensor device and the substrate to form a weld. The sensor device can be fixed to the substrate in a vertical orientation (e.g., in sensor assemblies 400 and 500) or a parallel orientation (e.g., in sensor assemblies 600, 700, 800, 900, and 1000). In embodiments, one or more alignment features can be used to ensure the correct orientation of the sensor device relative to the substrate.

[0189] In some embodiments where the substrate includes conductor pins extending over the entire outer and middle regions of the substrate into at least a portion of the inner region of the substrate (e.g., substrates 402 and 602), the method may further include the step of securing the conductor pins to an electrical contact pad (e.g., as described with sensor assemblies 400 and 600) in the inner region of the substrate, for example, with a third metal seal (e.g., via brazing).

[0190] At block 1130, the substrate is inserted into a slot in the housing (e.g., any of housings 404, 504, 604, 704, 904, or 1004 described above), such that the interior region of the substrate extends from the gas-facing surface of the housing. In some embodiments, the substrate is then coupled / secured to the housing using a second seal (e.g., via welding and / or brazing with a suitable brazing alloy) to form a sensor assembly. In some embodiments, the substrate may be secured to the housing at an outer region of the substrate, as shown with sensor assemblies 400, 500, and 600. In some embodiments, the substrate may be secured to the housing in a cantilever configuration at a middle region of the substrate, as shown with sensor assemblies 700 and 900. In some embodiments, the substrate may be inserted into two slots at opposite ends of the housing in an extended configuration and may be coupled / secured to the housing at two middle regions of the substrate, as shown with sensor assembly 800. In some embodiments, the substrate may be fixed to the housing via a face-to-face configuration in its intermediate region, as shown with sensor assembly 900. In some embodiments, the substrate may be fixed to a connector / flange via a face-to-face configuration in its intermediate region, and the connector / flange may be coupled (e.g., fused) to the housing, as shown with sensor assembly 1000 and described in more detail with reference to FIG11B.

[0191] In some embodiments, forming one or more of the metal seals / adhesives described herein (e.g., a first seal, a second seal, a third seal, and any additional metal seals) may include the steps of: brazing one component to another component (e.g., brazing a sensor device to a substrate, brazing a substrate to a housing, or brazing a conductor pin to an electrical contact pad), fusing one component to another component (e.g., via laser welding or electron beam welding), or bonding one component to another component using a metal adhesive formed from a single multilayer reactive foil. The brazing alloy used for any seal may independently include Al alloys, Ag alloys, Au alloys, Ni alloys, Si alloys, Au-Ni alloys, Ni-Pd alloys, Ni-Y alloys, Ti alloys, or combinations thereof. In some embodiments, another O-ring may be placed between the substrate and the housing (optionally, another cap configured to engage or compress the O-ring may be placed between the substrate and the housing) to enhance the hermetic seal between the substrate and the housing. In some embodiments, the seal provides an hermetically tight seal to minimize vacuum and / or hermetically tight leakage from the gas passage 240 to the external environment (e.g., minimizing leakage at the interface between the substrate and the housing, and / or minimizing leakage through a pinhole via a conductor needle). In some embodiments, one or more of the metal seals / adhesives described herein may include fusing one component to another (e.g., by electron beam welding, laser welding, etc.).

[0192] At block 1140, a conformal coating may be deposited onto the sensor assembly to at least coat a portion of the sensor assembly. This coating may be an anti-corrosion coating. In some embodiments, the conformal coating is a non-conductive material, such as a non-conductive ceramic material. In some embodiments, the conformal coating covers at least a portion of the sensing element 308. In other embodiments, the conformal coating covers the sensing region and is not coated, or only minimally coats the sensing element. In some embodiments, the coating covers part or all of the substrate (including its internal regions, one or more intermediate regions, and one or more external regions). In some embodiments, the coating covers part or all of the electrical contact pads on the substrate. In some embodiments, the coating covers part or all of the conductor pins extending from the substrate. In some embodiments, the coating covers part or all of various seals (e.g., seals between the substrate and the sensing device, seals between the substrate and the conductor pins, seals between the conductor pins and the electrical contact pads on the substrate, seals between the substrate and the housing, seals between the substrate and the connector / flange, and similar seals). In some embodiments, the sensor assembly is first assembled to form electrical contacts between all components of the sensor assembly (e.g., between the sensor device and the substrate and / or between the substrate and the conductor pin, if present). Thereafter, the assembled sensor assembly is coated such that the coating covers portions of the sensor assembly exposed to the airflow when the sensor assembly is coupled into an airflow channel. In some embodiments, the coating deposited on at least a portion of the sensor assembly may be similar to coatings described above suitable for coating at least a portion of the sensor assembly 400 (e.g., similar in deposition technique, coating composition / material, and / or coating uniformity, conformability, porosity, architecture, corrosion resistance, and the like). In some embodiments, the sensor assembly may remain completely uncoated.

[0193] In some embodiments, the conformal coating is deposited using one or more of ALD, IAD, LPPS, CVD, PS-CVD, or sputtering. In some embodiments, the conformal coating comprises a plasma-resistant ceramic coating, including rare earth ceramics selected from the following: Y₂O₃, YZrO, YxZryOz, YZrOF, Y₃Al₅O₁₂, Y₄Al₂O₉, YF₃, YxOyFz, YOF, Er₂O₃, Er₃Al₅O₁₂, ErF₃, ExOyFz, ErOF, La₂O₃, Lu₂O₃, Sc₂O₃, ScF₃, ScOF, Gd₂O₃, Sm₂O₃, Dy₂O₃, αY₂O₃-ZrO₂ solid solution, ceramics comprising Y₂Al₄O₉ and Y₂O₃-ZrO₂ solid solutions, or combinations thereof. In some embodiments, the conformal coating comprises Al₂O₃. In some embodiments, the conformal coating comprises Al₂O₃ deposited by ALD. In some embodiments, the conformal coating comprises multiple layers. In some embodiments, the thickness of the conformal coating is from about 10 nanometers to about 500 nanometers, or any subrange or single value thereof.

[0194] In some embodiments, a method for manufacturing a sensor assembly (e.g., the sensor assembly described in FIG. 10D) follows method 1200, shown as a flowchart in FIG. 11B and as an illustration in FIG. 11C. First, according to block 1210, a substrate (e.g., substrate 1002) having an outer region 1002O, an inner region 1002I, and a middle region 1002M (located between the outer region 1002O and the inner region 1002I) is provided. Then, according to block 1220, a metal flange / mate 1300 can be fixed to the substrate in a parallel, face-to-face configuration between the substrate-facing side of the flange / mate 1300 and a first side of the middle region 1002M of the substrate via a first seal 1300A. Then, according to block 1230, a supporting ceramic ring 1500 can be fixed in a parallel, face-to-face configuration between the substrate-facing side of the supporting ceramic ring and the housing-facing side of the flange / mate 1300 via a second seal 1300B.

[0195] Subsequently, according to block 1240, a sensor device (e.g., sensor device 300) can be fixed to the inner region 1002I of the substrate 1002, such that the electrical contacts on the sensor device contact the electrical contact pads on the substrate to establish a continuous and closed circuit for transmitting signals from the sensor device to a processing device (e.g., processing device 230). In some embodiments, the sensor device can be fixed to the substrate by forming a third seal 1300C between the electrical contact pads on the substrate and the electrical contacts on the sensor device. The sensor device can be fixed to the substrate in a vertical or parallel orientation.

[0196] Subsequently, according to block 1250, substrate 1002 (which is assembled with metal flange 1300 and sensor device, the flange being double-braced to the substrate on one side and to ceramic support ring 1500 on the other side) can be inserted into a slot in a housing (e.g., 1004 described above), such that the interior region of the substrate extends from the gas-facing surface of the housing. In some embodiments, according to block 1250, the metal flange 1300 is then coupled / secured to the housing with a fourth seal 1300D (which can be welded (e.g., electron beam welding), soldered, and / or brazed with a suitable brazing alloy) to form a sensor assembly (e.g., sensor assembly 1000). In some embodiments, the substrate can be cantilevered to the housing in a middle region of the substrate. In some embodiments, the substrate can be inserted into two slots at two opposite ends of the housing in an extended configuration and can be coupled / secured to the housing in two middle regions of the substrate. In some embodiments, at least a portion of the substrate assembly assembled according to method 1200 may be coated, as described in relation to block 1140 of method 1100 above and throughout this specification for various sensor assemblies. In some embodiments, the substrate assembly assembled according to method 1200 may remain completely uncoated.

[0197] Subsequently, regardless of whether the sensor assembly is manufactured according to method 1100 in FIG. 11A or method 1200 in FIG. 11B, the sensor assembly can be mounted to the airflow channel or attached (e.g., welded) to piping, or attached (e.g., via threaded fasteners) to the air rod assembly, for example, by means of suitable connectors (e.g., one or more VCR connectors). The sensor assembly can further be connected to one or more external devices (e.g., processing device 230) to form a closed airflow measurement and control circuit. In some embodiments, prior to connecting the sensor assembly to the one or more external devices, certain portions of the sensor assembly (e.g., the outer portion of the conductor needle in sensor assembly 600) can be at least partially decoated (e.g., laser etched) to expose conductive portions that can be connected to the external devices to form a closed circuit during operation.

[0198] For ease of explanation, the methods disclosed herein are depicted and described as a series of actions. However, unless otherwise stated, the actions according to this disclosure may occur in various sequences and / or in parallel, and may occur together with other actions not presented or described herein. Furthermore, not all of the actions shown are required to implement the methods according to the disclosed subject matter. Moreover, those skilled in the art will understand that the methods may alternatively be represented as a series of interrelated states via state diagrams or events. Furthermore, it should be understood that the methods disclosed herein can be stored on an article of manufacture to facilitate the transport and transfer of instructions for performing the methods to a computing device. The term "article of manufacture" as used herein is intended to include computer programs accessible from any computer-readable device or storage medium.

[0199] Figure 12A illustrates a cross-sectional side view of a sensor assembly 1201A according to an embodiment of the present disclosure. In some embodiments, the sensor assembly 1201A includes a substrate 1202 (e.g., substrate 402, 502, 602, 702, 802, 902, or 1002). The substrate may include electrical contact pads 1214 (e.g., electrical contact pads 414, 514, 614, 714, 814, 914, or 1014). In some embodiments, the sensor assembly 1201A includes a sensor device 300 coupled (e.g., bonded, adhered, attached, etc.) to the substrate 1202 (e.g., at an inner portion of the substrate 1202). In some embodiments, the substrate 1202 is a ceramic substrate. In some embodiments, the substrate 1202 may be a plastic substrate. In some embodiments, the substrate 1202 is an insulating substrate. The substrate 1202 may be electrically and / or thermally insulating. In some embodiments, the substrate 1202 is a dielectric substrate. Substrate 1202 may be a multilayer ceramic substrate, a PCB substrate, or a ceramic substrate. In some embodiments, substrate 1202 may include a PCB ceramic coating. In some embodiments, substrate 1202 may include a PCB insulating polymer (e.g., polyimide). As described above and below with reference to FIG. 12B, substrate 1202 may be joined to the connector / flange 1300 by brazing (e.g., with a suitable brazing alloy), by fusion, and / or by another technique. In some embodiments, connector / flange 1300 is coupled to housing 1204 (e.g., housing 704, 904, or 1004) by one or more screws 1278. Screws 1278 may be threaded fasteners (e.g., screws, bolts, etc.). O-rings 1280 may be disposed between connector / flange 1300 and the top surface of housing 1204. Screws 1278 may be tightened to seal connector / flange 1300 to housing 1204. When screw 1278 is tightened, O-ring 1280 can be compressed and form an airtight seal.

[0200] Figure 12B illustrates a cross-sectional side view of the sensor assembly 1201B according to an embodiment of this disclosure. In some embodiments, the connector / flange 1300 is brazed to the housing 1204 along brazing line 1203. As described above, the connector / flange 1300 can be brazed using a suitable brazing alloy. The connector / flange 1300 can be brazed to the housing 1204 to form an hermetically tight seal.

[0201] Figure 13A illustrates a cross-sectional side view of the connector / flange, multilayer ceramic substrate, and sensor device according to an embodiment of the present disclosure. Figure 13B illustrates an disassembled cross-sectional side view of the connector / flange, multilayer ceramic substrate, and sensor device according to an embodiment of the present disclosure.

[0202] Substrate 1302 (e.g., substrates 402, 502, 602, 702, 802, 902, or 1002) may be coupled to flange 1399 (e.g., a connector / flange 1300). In some embodiments, flange 1399 includes recess 1303 to receive features of substrate 1302. Recess 1303 may be a circular recess formed in the surface of flange 1399 to position substrate 1302 such that sensor device 300 is positioned at a predetermined location in a gas tube (e.g., a gas tube in housing 704, 904, or 1004). Recess 1303 may prevent substrate 1302 from moving relative to flange 1399. Substrate 1302 may be inserted through a hole in flange 1399 until features of substrate 1302 are locked into recess 1303. In some embodiments, substrate 1302 may be configured to be coupled to a gas flow tube (e.g., via flange 1399).

[0203] Figures 14A-14D illustrate various alignment features that can be used to position, align, and / or orient a sensor device relative to a substrate in embodiments. In embodiments, sensor features can ensure that the sensor device has a targeted orientation (e.g., rotation, tilt, etc.) and positioning relative to the substrate in one or more planes. In embodiments, these alignment features can be used for any sensor assembly of Figures 4A-10D.

[0204] Figure 14A illustrates a side view of the substrate 1402 (e.g., a ceramic substrate) and the sensor device 1401 after the sensor device 1401 has been positioned and oriented relative to the substrate 1402 for bonding, according to an embodiment of the present disclosure. Figure 14B illustrates a disassembled side view of the substrate 1402 and the sensor device 1401 before the sensor device 1401 is positioned relative to the substrate 1402, according to an embodiment of the present disclosure. Figures 14A-14B show a system 1400 for aligning and / or attaching the sensor device 1401 to the substrate 1402, according to an embodiment of the present disclosure. As shown in Figures 14A-B, the sensor device 1401 is oriented such that the sensor surface of the sensor device 1401 is orthogonal to the direction of the airflow 1450, where the airflow is in the X direction.

[0205] Sensor device 1401 may correspond to sensor device 300 and may be coupled (e.g., attached, bonded, etc.) to substrate 1402 (which may correspond to substrates 402, 502, 602, 702, 802, 902, or 1002) using one or more alignment features. These one or more alignment features may align sensor device 1401 relative to substrate 1402 within a first plane and / or a second plane (e.g., the first plane is parallel to the airflow through the housing of the sensor assembly and / or perpendicular to the interface between sensor device 1401 and substrate 1402, and the second plane is substantially perpendicular to the first plane, e.g., parallel to the interface between sensor device 1401 and substrate). In some embodiments, these one or more alignment features result in sensor device 1401 being positioned at a target location on substrate 1402 such that the sensor die is centered in the gas channel during use. In some embodiments, the one or more alignment features cause the sensor device 1401 to be positioned such that the sensor device 1401 is substantially decisively positioned in the gas channel during use of the sensor assembly. In one embodiment, the first plane in which the orientation of the sensor device 1401 relative to the substrate 1402 is controlled is the XY plane as shown in FIG14A-B. Therefore, the alignment features of the sensor device and the substrate can control the tilt of the sensor device relative to the airflow direction in the XY plane.

[0206] In some embodiments, as shown in FIG14A, alignment features include one or more alignment features 1412 (e.g., one or more protrusions) extending from sensor device 1401 and corresponding one or more recesses or holes in the substrate, which are positioned and shaped to receive the one or more protrusions. Alignment features may additionally or alternatively include one or more recesses or holes in sensor device 1401 and corresponding protrusions in the substrate, which are configured to fit into the one or more recesses or holes. Alignment features may additionally or alternatively include one or more alignment marks 1422, which can be used by a technician or vision-assisted robotic arm to position and orient sensor device 1401 relative to substrate 1402.

[0207] In some embodiments, the alignment feature additionally or alternatively includes a recess or notch 1420 in the substrate, which is shaped to be part of the receiving sensor device 1401. For example, as shown in Figures 14A-14B, a portion of one end and both sides of the sensor device 1401 are tightly fitted into the recess 1420. The recess 1420 can provide stability to the sensor device 1401, can limit the degrees of freedom of possible position / orientation of the sensor device 1401 relative to the substrate 1402, and / or can control the positioning of the sensor device 1401 on the substrate 1402 (to ensure, for example, that when the sensor assembly is mounted in a gas assembly or gas conduit, the sensor device 1401 is centered in a plane orthogonal to the gas flow direction).

[0208] In some embodiments, sensor device 1401 includes alignment features 1412, and substrate 1402 includes alignment features 1414, which together align sensor device 1401 relative to substrate 1402. Alignment features 1412 and 1414 can control the tilt of sensor device 1401 relative to substrate 1402 within a first plane parallel to the interface between sensor device 1401 and substrate 1402. In some embodiments, alignment feature 1412 includes a ridge / protrusion, and alignment feature 1414 includes a corresponding groove / hole / recess to receive the ridge / protrusion of alignment feature 1412. In some embodiments, alignment feature 1412 includes a substantially cylindrical protrusion, and alignment feature 1414 includes a corresponding cylindrical hole to receive the cylindrical protrusion. In some embodiments, alignment feature 1412 includes a conical protrusion, and alignment feature 1414 includes a corresponding conical hole to receive the conical protrusion. Using conical protrusions and holes simplifies the process of placing alignment feature 1412 into alignment feature 1414. In some embodiments, alignment features 1412 and 1414 have square, rectangular, trapezoidal, circular, oval, spherical, dome-shaped, or other shapes. In embodiments, the shape of alignment feature 1412 is the negative of the shape of alignment feature 1414, or the shape of alignment feature 1414 is the negative of the shape of alignment feature 1412, so that the mating of alignment features 1412 and 1414 can be controlled. In some embodiments, the alignment feature may be inside and / or outside the substrate 1402 and / or sensor device 1401. In some embodiments, alignment feature 1414 is machined into substrate 1402 by a computer-controlled machining process. Alignment feature 1414 may be drilled or milled into the surface of substrate 1402. In some embodiments, alignment feature 1412 may be glued to case 1416 (e.g., plastic case).

[0209] In some embodiments, two pairs of opposing alignment features are used (e.g., a first pair of alignment features 1412 and corresponding alignment features 1414, and a second pair of alignment features 1412 and corresponding alignment features 1414). In one embodiment, at least three pairs of opposing alignment features are used (e.g., a first pair of alignment features 1412 and corresponding alignment features 1414, a second pair of alignment features 1412 and corresponding alignment features 1414, and a third pair of alignment features 1412 and corresponding alignment features 1414).

[0210] In some embodiments, the sensor device 1401 includes one or more lateral protrusions 1410 extending laterally from the sensor device 1401. In embodiments, the lateral protrusions 1410 may extend in a plane parallel to the top surface of the sensor device 1401. In embodiments, each lateral protrusion may each include one or more alignment features (e.g., at their distal ends) that extend orthogonally to the plane parallel to the top surface of the sensor device 1401.

[0211] As previously described, the sensor device 1401 may be formed, for example, of silicon or another material. The sensor device 1401 may be connected to a case 1416 (e.g., a plastic box), and alignment features 1412 and / or lateral protrusions 1410 may be coupled to the case 1416. In one example, the lateral protrusion 1410 may be a post coupled to the case 1416 of the sensor device 1401 to align the sensor device 1401 relative to the substrate 1402. In some embodiments, the protrusion 1410 may be a metal protrusion bonded to the case 1416. In some embodiments, the protrusion 1410 is machined by a computer-controlled machining process. Similarly, the protrusion 1410 may be bonded to the case 1416 using a computer-controlled robot and bonding process. In an embodiment, after the sensor device is bonded to the substrate 1402, the case can be removed from the sensor device 1401. As shown in the figures, in some embodiments, each of the lateral protrusions 1410 may include an alignment feature 1412 at its distal end. Alignment features 1414 may be configured to receive a corresponding alignment feature 1412 attached to a lateral protrusion 1410. In some embodiments, alignment features 1414 may be configured to receive a corresponding protrusion (e.g., a protrusion of alignment feature 1412). Each of the alignment features 1412 may be received by an alignment feature 1414 formed in a substrate 1402. In some embodiments (e.g., as shown in Figures 14A-B), sensor device 1401 may include three lateral protrusions 1410, each having a corresponding alignment feature 1412, and substrate 1402 includes three corresponding alignment features 1414. However, in some embodiments, system 1400 may include more or fewer lateral protrusions 1410, alignment features 1412, and / or alignment features 1414. Fitting each of the alignment features 1412 into the alignment feature 1414 can cause the sensor device to be aligned within a first plane (e.g., the plane of the page shown). In response to each of the alignment features 1412 being inserted into the corresponding alignment feature 1414, the sensor device 1401 can be substantially prevented from moving (e.g., laterally, or tilting, etc.) along a plane (e.g., the plane of the page shown).

[0212] In some embodiments, substrate 1402 includes one or more alignment marks (e.g., visual alignment features) 1422. Alignment marks 1422 can provide visual cues for the alignment of sensor device 1401 relative to substrate 1402 within a first plane. In one embodiment, alignment marks 1422 include L-shaped marks indicating where the corners of sensor device 1401 should be placed. A technician (e.g., an operator, engineer, assembler, etc.) or an assembly robot (e.g., via an imaging sensor) can verify the alignment of sensor device 1401 relative to alignment marks 1422 within the first plane. In some embodiments, alignment marks 1422 are etched onto substrate 1402. In some embodiments, marks 1422 are etched onto sensor device 1401.

[0213] Figure 14C illustrates a cross-sectional view of a substrate (e.g., a ceramic substrate) 1404 cooperating with a sensor device 1403 according to an embodiment of the present disclosure. Figure 14D illustrates a disassembled cross-sectional view of the substrate 1404 and the sensor device 1403 according to an embodiment of the present disclosure. Figures 14C-14D show views perpendicular to the views shown in Figures 14A-B. As shown, Figures 14A-14B are in the XY plane, and Figures 14C-14D are in the XZ plane. As shown, a set of alignment features 1418 (e.g., pillars or protrusions) of the substrate 1404 are inserted into a set of alignment features 1417 (e.g., holes or recesses) of the sensor device 1403. The set of alignment features 1417 and the set of alignment features 1418 are configured such that, in response to the set of alignment features 1417 receiving the set of alignment features 1418, the sensor device 1403 is substantially fixed relative to the substrate 1404 in a first plane (e.g., the XY plane).

[0214] While sensor device 1401 is described above as including one or more protrusions and substrate 1402 is described above as including one or more corresponding holes, it is contemplated that in some embodiments, substrate 1402 may also include one or more protrusions to be inserted into one or more alignment holes formed in sensor device 1401. Similarly, while substrate 1404 is described above as including one or more protrusions and sensor device 1403 is described above as including one or more corresponding holes, it is contemplated that in some embodiments, sensor device 1403 may also include one or more protrusions to be inserted into one or more alignment holes formed in substrate 1404.

[0215] Figures 15A-15D illustrate various alignment features that can be used to position, align, and / or orient a sensor device relative to a substrate in the embodiments. In the embodiments, sensor features can ensure that the sensor device has a targeted orientation (e.g., rotation, tilt, etc.) and positioning relative to the substrate in one or more planes. These alignment features can be used with any sensor assembly of Figures 4A-10D in the embodiments and can be combined with the alignment features of Figures 14A-14D in the embodiments.

[0216] Figures 15A-G illustrate a system for bonding a sensor device to a substrate 1502 (e.g., a ceramic substrate) according to embodiments of this disclosure. In some embodiments, the sensor device 1503 may correspond to the sensor device 300 and / or may be bonded to the substrate 1502 (e.g., substrates 402, 502, 602, 702, 802, 902, or 1002) by soldering, brazing, fusing, fusion, flash bonding (e.g., using multilayer reactive foil), or any combination thereof. Specifically, electrodes 1515 (e.g., electrical contacts) of the sensor device 1503 may be bonded to electrical contact pads 1514 of the substrate 1502. Electrodes 1515 may be bonded to electrical contact pads 1514 as described below. In embodiments, one or more alignment features (e.g., solder 1518, electrodes 1515, electrical contact pads 1514) may be used to align the sensor device 1503 to the substrate 1502. For embodiments where there is direct contact between the contact pad and the electrode, alignment features may include the contact pad / electrode of the sensor device and / or the substrate itself. Alignment features may additionally or alternatively include carefully controlled solder joints (e.g., having a uniform thickness) for bonding the contact pad to the electrode. In embodiments, alignment features may be used to control the orientation and / or tilt of the sensor device 1503 relative to the substrate 1502 in a plane perpendicular to the interface between the sensor device and the substrate (e.g., in the XZ plane).

[0217] Referring to FIG15A, a system 1501A for bonding a sensor device 1503 to a substrate 1502 is shown according to an embodiment of the present disclosure. In some embodiments, a certain amount of solder 1518 (e.g., solder bumps) may be placed on each of the electrical contact pads 1514. The solder 1518 may be generally spherical when placed on the electrical contact pads 1514. The top surface of the solder 1518 may then be flattened by a coining operation to produce a substantially cylindrical shape. The coining operation may flatten the solder 1518 to a controlled thickness. In some embodiments, the coining operation may flatten each of a plurality of solder bumps to a controlled thickness substantially similar to the controlled thickness of the remaining solder bumps in the plurality of solder bumps. Next, the sensor device 300 may be placed on the substrate 1502 such that the electrode 1515 contacts the flattened solder 1518. Solder 1518 can then be bonded to electrode 1515 to form a solder contact between sensor device 300 and substrate 1502. Solder 1518 can form a contact that couples electrode 1515 to electrical contact pad 1514. Since the solder contacts have a uniform thickness, the tilt of the sensor device relative to the substrate can be controlled or minimized. For example, due to the use of alignment features (e.g., finely pressed solder bumps 1518), sensor device 1503 can be parallel to substrate 1502. The one or more alignment features discussed with reference to Figures 14A-D may further include solder contacts as described above. In some embodiments, the solder contacts can align sensor device 300 within a second plane (e.g., the XZ plane).

[0218] Referring to FIG. 15B, a system 1501B for bonding a sensor device 1503 to a substrate 1502 is shown according to an embodiment of the present disclosure. In some embodiments, the sensor device 1503 is placed in a jig 1512. In some embodiments, the substrate 1502 is placed in the jig 1512. The jig 1512 may have a recess to receive the sensor device 1503. In some embodiments, the jig 1512 includes a vacuum port 1504. A vacuum may be provided at the vacuum port 1504 to hold the sensor device 1503 in the jig 1512 during bonding processes (e.g., bonding processes as described herein). The sensor device 1503 may be placed in the jig 1512 such that electrodes 1515 are exposed (e.g., face up, as shown). The substrate 1502 may be placed on the sensor device 1503. In some embodiments, the substrate 1502 forms a through-hole 1516. Electrical contact pads 1514 may extend from the surface of substrate 1502 into each via 1516. The vias 1516 may be aligned with electrodes 1515. In some embodiments, substrate 1502 forms two vias 1516, and the sensing device includes two electrodes 1515. Each via 1516 may be aligned with one of the two electrodes 1515. Substrate 1502 may be placed on (e.g., adjacent to) sensing device 1503. Solder 1518 may be placed in the vias 1516 to at least partially fill the vias 1516. In some embodiments, solder 1518 at least partially fills the vias 1516. Solder 1518 may make electrical contact between electrodes 1515 and electrical contact pads 1514. Solder 1518 may form solder contacts between substrate 1502 and sensing device 1503. In some embodiments, the one or more alignment features described above include solder contacts discussed herein. The solder joints discussed here enable the sensor device 1503 to be aligned in the second plane.

[0219] Referring to FIG15C, a system 1501C for bonding a sensor device to a substrate is shown according to an embodiment of the present disclosure. In some embodiments, an electrical contact pad 1514 may be disposed between two layers of the substrate 1502. In this embodiment, the electrical contact pad 1514 may be exposed within the inner surface of a via 1516. Furthermore, in some embodiments, a laminate 1526 may be deposited on solder 1518. The laminate 1526 may be deposited on a portion of the surface of the substrate 1502 near the via 1516. In some embodiments, the laminate 1526 may be a conformal coating, as described above. The laminate 1526 may be an anti-corrosion layer to protect the solder 1518 and / or the contacts formed between the sensor device 300 and the substrate 1502. The solder 1518 may form solder contacts between the substrate 1502 and the sensor device 1503. In some embodiments, the one or more alignment features described above include the solder contacts discussed herein. The solder joints discussed here enable the sensor device 1503 to be aligned in the second plane.

[0220] Referring to FIG15D, a system 1501D for bonding a sensor device to a substrate is shown according to an embodiment of the present disclosure. In some embodiments, an electrical contact pad 1514 of the substrate 1502 may be positioned to contact an electrode 1515 of the sensor device 1503. In some embodiments, the radiation of the welder may be directed towards a metallic contact area formed by the electrical contact pad 1514 and the electrode 1515. The metallic contact area may be irradiated with radiation 1524 to create a fusion contact 1522 (e.g., by ultraviolet, infrared, or CO2 laser radiation). In some embodiments, a laser beam may be used to irradiate the electrical contact pad 1514 and the electrode 1515. The irradiated electrical contact pad 1514 and electrode 1515 may be heated by radiation 1524 and at least partially melted. The electrical contact pad 1514 and electrode 1515 may fuse upon cooling. In some embodiments, the metallic contact area functions as one of the alignment features described above. In some embodiments, the fusion contact between the electrical contact pad and the electrode functions as one of the alignment features described above.

[0221] In some embodiments, to facilitate the fusion of electrical contact pads 1514 and electrodes 1515 by irradiation (e.g., via emitted radiation 1524), substrate 1502 and / or sensor device 1503 are substantially transparent to the wavelength of the radiation 1524 used. For example, substrate 1502 may be substantially transparent to a laser beam of a given wavelength used for fusing electrical contact pads 1514 and electrodes 1515. As used herein, "substantially transparent" means that at least about 80% or at least 90% or more of the radiation 1524 is transmitted through substrate 1502 and / or sensor device 1503 (e.g., up to 20% absorption). In some embodiments, substrate 1502 may be made of glass, quartz, or silicate material. In such embodiments, substrate 1502 may be sufficiently transparent to the wavelength of radiation 1524 emitted from a radiation source to heat electrical contact pads 1514 and electrodes 1515 to their melting point. In some embodiments, the transparency of substrate 1502 and / or sensor device 1503 may be increased by reducing reflection. In some embodiments, the surfaces of the substrate 1502 and the sensor device 1503 may be textured to increase transparency.

[0222] In some embodiments, the electrical contact pad 1514 and the electrode 1515 are made of different metals. In other embodiments, the electrical contact pad 1514 and the electrode 1515 are made of the same metal (e.g., platinum). In some embodiments, the electrical contact pad 1514 and the electrode 1515 are made of metals that can be compatibly fused together as described above.

[0223] Referring to FIG15E, a system 1501E for bonding a sensor device 1503 to a ceramic substrate 1502 is shown according to an embodiment of the present disclosure. In some embodiments, an electrical contact pad 1514 and an electrode 1515 are bonded with a metal adhesive. As described above, in some embodiments, the electrical contact pad 1514 and the electrode 1515 comprise platinum conductors. The metal adhesive may comprise one or more layers of a metal selected from platinum, tin, indium, copper, aluminum, and / or nickel. In some embodiments, the metal adhesive comprises a metal that is corrosion-resistant and / or chemically compatible with the gases to be flowed through the sensor assembly, to which the substrate 1502 and the sensor device 1503 are part. In some embodiments, the metal adhesive comprises one or more metal adhesive layers. In one embodiment, each metal adhesive layer may comprise aluminum and / or nickel. The metal adhesive provides an electrical connection between the electrode 151 and the electrical contact pad 1514.

[0224] The metal binder can mechanically bond the electrical contact pad 1514 and the electrode 151, and can be produced using a single layer of multilayer reactive foil 1519. In one embodiment, a single layer of metal binder material comprising aluminum and / or nickel is used. Alternatively, other metals may be used. Furthermore, the metal binder may include a thin layer of aluminum and / or nickel (with a thickness of, for example, about 2-4 mils in one embodiment) between two other metal layers (e.g., between two tin layers). In one embodiment, this thin layer is initially a reactive multilayer foil (referred to herein as a reactive foil) composed of alternating nanoscale layers of reactive materials such as aluminum and nickel. During a room-temperature metal bonding process, the reactive foil can be activated (e.g., ignited), resulting in a near-instantaneous reaction and temperatures exceeding 1500 degrees Celsius. This can cause the upper and lower metal layers, acting as solder, to melt and reflow to bond the electrode 1515 to the electrical contact pad 1514. In one embodiment, the reactive foil is NanoFoil® manufactured by Indium Corporation, USA.

[0225] In one example, foil 1519 may comprise alternating layers of nickel alloy and aluminum alloy. Foil 1519 may be cut into tabs and disposed between electrical contact pad 1514 and electrode 1515. During the manufacturing process, as discussed below with reference to FIG. 16B, in some embodiments, foil 1519 may be ignited (e.g., by applying current to foil 1519) to cause foil 1519 to reactively adhere to both electrical contact pad 1514 and electrode 1515. For example, a voltage may be applied to foil 1519 to induce current through foil 1519, causing foil 1519 to reactively adhere and conform to the shape of electrical contact pad 1514 and / or electrode 1515. In some embodiments, the adhesive produced by the reactively adhered foil 1519 is a conductive adhesive between electrical contact pad 1514 and electrode 1515. In some embodiments, an anti-corrosion coating is disposed on the exposed portion of the adhesive. The anti-corrosion coating can be a single layer of perfluoropolymer, a silyl coating (e.g., fluorinated alkyl silane coating, perfluorooctyltriethoxysilane coating, etc.), or an inorganic oxide coating.

[0226] Referring to FIG15F, a system 1501F for bonding a sensor device to a ceramic substrate is shown according to an embodiment of the present disclosure. In some embodiments, a metal adhesive layer 1517 is deposited on an electrical contact pad 1514 and / or an electrode 1515. In some embodiments, one or more metal adhesive layers 1517 are deposited on the electrical contact pad 1514 and / or the electrode 1515. The metal adhesive layer 1517 may facilitate bonding a multilayer reactive foil 1519 to the electrical contact pad 1514 and / or the electrode 1515. In some embodiments, the metal adhesive layer 1517 may be an aluminum alloy layer or a nickel alloy layer. The foil 1519 may be disposed on the metal adhesive layer 1517 of either the electrical contact pad 1514 or the electrode 1515 prior to bonding. The electrical contact pad 1514 and the electrode 1515 may be bonded via the multilayer reactive foil 1519, as described above with reference to FIG15E.

[0227] Referring to FIG. 15G, a system 1501G for bonding a sensor device 1503 to a substrate 1502 is shown according to an embodiment of the present disclosure. In some embodiments, the sensor device 1503 may be bonded to the substrate 1502 via one or more fused contacts. For example, the sensor device 1503 may be fused to the substrate 1502 (e.g., via electrodes 1515 and electrical contact pads 1514). Metal wires 1521 (e.g., platinum wires) may be fused to each electrode 1515. The metal wires 1521 may be fused to each electrode 1515 by a fusion operation (e.g., electron beam fusion or laser fusion). Alternatively, the electrodes 1515 may be metal wires (e.g., platinum wires) extending from the sensor device 1503. The sensor device 1503 may be placed on the substrate 1502 such that at least a portion of the metal wires 1521 covers the respective electrical contact pads 1514. The metal wire 1521 can be fused to the electrical contact pad 1514 by another fusion operation (such as electron beam fusion or laser beam fusion). The metal wire 1521 fused to the electrical contact pad 1514 and / or the electrode 1515 can bond the sensor device 300 to the substrate 1502.

[0228] In some embodiments, bonded contacts (e.g., solder contacts, fusion contacts, welded contacts, etc.) formed by processes and methods described with reference to Figures 15A-G are included by one or more alignment features as described above. The bonded contacts can align and / or fix the sensor device 300 relative to the substrate 1502 in a first plane and a second plane.

[0229] Figures 16A-C illustrate flowcharts of a method for manufacturing a sensor assembly according to an embodiment of the present disclosure. Referring to Figure 16A, a flowchart of a method 1600A for manufacturing a sensor assembly according to an embodiment of the present disclosure is shown.

[0230] At block 1602, in some embodiments, a substrate having an outer region, an inner region, and a middle region is provided. The substrate may further include one or more electrical contact pads located at least in the inner region. The substrate may be a multilayer ceramic substrate.

[0231] At block 1604, in some embodiments, a sensor die (e.g., sensor device 300) is coupled to a substrate via one or more alignment features that align the sensor die relative to the substrate within at least one of a first or second plane. These one or more alignment features may be protrusions (e.g., lateral protrusions 1410 of Figures 14A-D), alignment marks (e.g., visual alignment features, such as visual alignment feature 1422 of Figures 14A-14B), and / or one or more adhesives (e.g., metal adhesives, fusion adhesives, weld adhesives, fusion adhesives, etc.). In some embodiments, at block 1606, a first set of protrusions from the sensor die is inserted into a first set of alignment holes (e.g., alignment holes of Figures 14A-D) formed in the substrate. In some embodiments, this first set of protrusions protrudes from a plastic case (e.g., case 1416 of Figures 14A, B) bonded to the sensor device. Then, while the alignment features of the sensor device (e.g., protrusions, solder bumps, etc.) engage with the alignment features of the substrate (e.g., holes, solder bumps, etc.), the sensor device can be bonded to the substrate.

[0232] At block 1608, in some embodiments, the substrate is coupled to the housing at an outer region of the substrate to provide an hermetically tight seal. As described above, the substrate may be welded and / or brazed to the housing. In some embodiments, the substrate may be coupled to the housing via a flange (e.g., flange / mater 1300).

[0233] Referring to FIG16B, a flowchart of a method 1600B for manufacturing a sensor assembly is shown according to an embodiment of the present disclosure. In some embodiments, at block 1612, a substrate is provided. The substrate may have an outer region, an inner region, and an intermediate region. The substrate may further include one or more electrical contact pads located at least on the inner region. At block 1614, in some embodiments, a sensor die (e.g., sensor device 300) is provided. The sensor die may have one or more electrodes.

[0234] At block 1616, in some embodiments, a multilayer reactive foil is disposed on each of the electrodes of the one or more electrical contact pads and / or sensor bare crystals of the substrate. The multilayer reactive foil may comprise multiple alternating layers of two reactive metals (e.g., nickel and aluminum). In some embodiments, a metal adhesion layer (e.g., an aluminum alloy layer or a nickel alloy layer) is deposited onto the electrical contact pads and / or electrodes before the multilayer reactive foil is disposed on the one or more electrical contact pads and / or electrodes.

[0235] At block 1618, in some embodiments, the sensor die is positioned onto an internal region of the substrate such that a sheet of multilayer reactive foil is sandwiched between one or more electrical contact pads and one or more electrodes. At block 1620, in some embodiments, the sheet of multilayer reactive foil can be ignited to form a metal bond between the one or more electrical contact pads of the substrate and the one or more electrodes of the sensor die. In some embodiments, the multilayer reactive foil can be ignited by inducing a current through the foil (e.g., by applying a voltage to the foil). The metal bonding process using reactive multilayer foil can be a room-temperature metal bonding process, wherein the reactive foil can be activated (e.g., ignited) to create a near-instantaneous reaction of over 1500 degrees Celsius at the interface of the two surfaces to be bonded. This can cause the upper and lower metal layers (e.g., metal bond layers) that can act as solder to melt and reflow to bond the electrodes to the electrical contact pads.

[0236] In some embodiments, after the metal bonding process is completed (e.g., via ALD, CVD, etc.), an anti-corrosion coating (e.g., an anti-corrosion coating as discussed above) is deposited at least on the exposed portion of the metal bond.

[0237] At block 1622, in some embodiments, the substrate is coupled to the housing in the outer region to provide an hermetic seal. As described above, the substrate may be welded and / or brazed to the housing. In some embodiments, the substrate may be coupled to the housing via a flange (e.g., flange / mater 1300).

[0238] Referring to FIG16C, a flowchart of a method 1600C for manufacturing a sensor assembly is shown according to an embodiment of the present disclosure. In some embodiments, at block 1632, a substrate is provided. The substrate may have an outer region, an inner region, and an intermediate region. The substrate may further include one or more electrical contact pads located at least on the inner region. At block 1634, in some embodiments, a sensor die (e.g., sensor device 300) is provided. The sensor die may include one or more electrodes.

[0239] At block 1636, in some embodiments, a metal wire can be bonded to each of the one or more electrodes by a first fusion operation. In some embodiments, the one or more electrodes comprise platinum, and the metal wire may be a platinum wire. The first fusion operation may be a laser fusion operation or an electron beam fusion operation. A first end of the metal wire may be bonded to each electrode by the fusion operation. In some embodiments, the electrode itself is a metal wire extending from the sensing device, thus the operation at block 1636 can be skipped.

[0240] At block 1638, in some embodiments, the sensor die is positioned onto an internal region of the substrate such that at least a portion of the metal wire or electrode covers a corresponding electrical contact pad in one or more electrical contact pads. At block 1640, in some embodiments, the metal wire is bonded to the corresponding electrical contact pad by a second welding operation (or a first welding operation, if the electrode is a metal wire). The welding operation can be a laser welding operation or an electron beam welding operation. In some embodiments, the welding operation includes welding along a first side and a second side of the metal wire. The welding operation can bond the corresponding metal wire to the corresponding electrical contact pad.

[0241] At block 1642, in some embodiments, the substrate is coupled to the housing in the outer region to provide an hermetic seal. As described above, the substrate may be welded and / or brazed to the housing. In some embodiments, the substrate may be coupled to the housing via a flange (e.g., flange / mater 1300).

[0242] Figures 16D-F illustrate flowcharts of methods for bonding a sensor device to a substrate according to embodiments of the present disclosure. Referring to Figure 16D, a flowchart of method 1600D for bonding a sensor device to a substrate is illustrated according to embodiments of the present disclosure. At block 1652, in some embodiments, a first solder bump is placed on a first electrical contact pad (e.g., an electrical contact pad of the substrate). At block 1654, in some embodiments, a second solder bump is placed on a second electrical contact pad. The first and second solder bumps may include a first amount of solder. In some embodiments, the first and second solder bumps are generally spherical.

[0243] At block 1656, in some embodiments, the block includes the step of flattening the top surface of each of the first and second solder bumps by a preforming process. The preforming process can form each of the first and second solder bumps into a substantially cylindrical shape. The preformed solder bumps may each have the same or substantially the same size and / or thickness. At block 1658, in some embodiments, the first and second electrodes of the sensor die are placed on the top surfaces of the flattened first and second solder bumps to bond the sensor die to the substrate. In some embodiments, the sensor die is placed on the substrate by an end effector of a robotic arm (e.g., a robotic arm manufacturing a robot). Electrical connectivity can be established between the sensor die and the substrate via electrical contact pads, solder bumps, and electrodes. Soldering or fusion can then be performed to bond the electrical contact pads to the electrodes using the solder bumps.

[0244] Referring to FIG16E, a flowchart illustrating a method 1600E for bonding a sensor device to a substrate is described according to an embodiment of the present disclosure. At block 1662, in some embodiments, a sensor die is placed in a fixture. The first and second electrodes of the sensor die may be exposed in response to the sensor die being placed in the fixture. For example, the sensor die may be placed in a recess of the fixture with the electrode face upward (e.g., as shown in FIG15B).

[0245] At block 1664, in some embodiments, a first via and a second via formed by the substrate are aligned with a first electrode and a second electrode, respectively. In block 1666, the substrate may be positioned adjacent to the sensor die (e.g., placed on the sensor die). In some embodiments, the substrate is placed on the sensor die by the end effector of a robotic arm (e.g., the end effector of a manufacturing robot).

[0246] At block 1668, in some embodiments, the first via and the second via are each filled with a first amount of solder to bond the sensor die to the substrate. In some embodiments, the first amount of solder may at least partially fill the first and second vias. The solder may establish electrical connectivity between the sensor die and the substrate via electrodes and electrical contact pads.

[0247] At block 1670, in some embodiments, a laminate is deposited on the solder. The laminate can protect the solder from harmful environmental chemicals present when the sensor assembly is used (e.g., in the system described with reference to FIG. 1). The laminate can be deposited on the solder and on at least a portion of the substrate surface adjacent to the first and second vias.

[0248] Referring to FIG16F, a flowchart of a method 1600F for bonding a sensor device to a substrate is illustrated according to an embodiment of the present disclosure. At block 1672, in some embodiments, a sensor die is placed on the substrate, with the electrodes of the sensor die resting on electrical contact pads of the substrate. In some embodiments, the sensor die is placed by an end effector of a robotic arm (e.g., a robotic arm manufacturing a robot).

[0249] At block 1674, in some embodiments, the electrodes and / or electrical contact pads are irradiated to fuse the electrodes with the electrical contact pads. In some embodiments, the electrodes and / or electrical contact pads are irradiated with a radiation source. The radiation source may be a laser radiation source, a UV radiation source, and / or an infrared radiation source. In some embodiments, the radiation source is a CO2 laser. In some embodiments, the sensor die and / or substrate are made of a material that is substantially transparent to a predetermined radiation wavelength, as described above with reference to FIG. 15D. The fusion of the electrodes and electrical contact pads can establish electrical connectivity between the sensor die and the substrate via the electrodes and electrical contact pads.

[0250] For ease of explanation, the methods disclosed herein are depicted and described as a series of actions. However, unless otherwise stated, the actions according to this disclosure may occur in various sequences and / or in parallel, and may occur together with other actions not presented or described herein. Furthermore, not all of the actions shown are required to implement the methods according to the disclosed subject matter. Moreover, those skilled in the art will understand that the methods may alternatively be represented as a series of interrelated states via state diagrams or events. Furthermore, it should be understood that the methods disclosed herein can be stored on an article of manufacture to facilitate the transport and transfer of instructions for performing the methods to a computing device. The term "article of manufacture" as used herein is intended to include computer programs accessible from any computer-readable device or storage medium.

[0251] In some embodiments, a sensor assembly including a substrate, a sensor die / sensor device, and a housing includes one or more channels providing a gas flow path. In this embodiment, the housing may not be fixed to a gas duct to extend the sensor die / sensor device into the gas flow path within the gas duct. Instead, the gas flow path can be diverted through the one or more channels of the sensor assembly and then returned to the gas duct. An example of a sensor assembly configuration that includes its own channels to provide a gas flow path is a sensor assembly configuration designed for use with a gas spring assembly. The sensor assembly may be configured to fit in size and shape to a standard base (e.g., a base typically receiving valves, filters, or other components for a gas spring assembly) on the base of the gas spring assembly. In this embodiment, the substrate may be disposed within at least a portion of the housing, and the sensor device / sensor die coupled to the substrate may be located within an internal channel of the housing. In an embodiment, the sensor device / sensor die is located at the center of the cross-section of the channel within the housing.

[0252] Figures 17A-17H illustrate embodiments of sensor components that can be used on a pneumatic rod assembly.

[0253] Figure 17A illustrates a perspective view of the sensor assembly 1700A according to an embodiment of this disclosure. Figure 17B illustrates a front view of section EE in Figure 17A. Figure 17C illustrates an disassembled front view of section EE in Figure 17A. Figure 17D illustrates a front view of section FF in Figure 17A.

[0254] In some embodiments, sensor assembly 1700A includes housing 1708. In some embodiments, housing 1708 is made of a stainless steel alloy. Alternatively, housing 1708 may be made of any housing material discussed elsewhere herein. Housing 1708 may be substantially cubic in shape, or may have a cylindrical or other shape. Housing 1708 may include one or more holes for mounting on the base of a pneumatic rod assembly (e.g., a base on the base of a pneumatic rod assembly (e.g., pneumatic rod assembly 1750 of FIG. 17H-I)). Furthermore, the one or more holes for mounting may be configured to couple housing 1708 to an auxiliary component. The bottom surface of sensor assembly 1700A may be sealed to the base or base of the pneumatic rod assembly, and the top surface of sensor assembly 1700A may optionally be sealed to an auxiliary component (e.g., a filter or valve). These holes may be configured to accept fasteners (e.g., screws or bolts) to secure sensor assembly 1700A to the pneumatic rod assembly. The top and bottom surfaces of the housing 1708 may include one or more recessed or grooved areas configured to receive a sealing element (e.g., a metal seal). Once the housing 1708 is fastened to the base and / or auxiliary components of the air spring assembly via fasteners, the sealing element can be compressed, and a seal can be formed between the housing 1708 and the base of the air spring assembly and / or between the housing 1708 and the auxiliary components.

[0255] Housing 1708 may include one or more airflow channels. For example, housing 1708 may form a first channel configured to allow gas to flow in a first direction (e.g., vertically upward in FIG. 17B) (e.g., from a gas rod assembly, airflow assembly, etc.). Housing 1708 may further form a second channel configured to allow gas to flow in a second direction (e.g., vertically downward in FIG. 17B). The second direction may be opposite to the first direction. For example, the first channel may allow gas to flow upward, while the second channel may allow gas to flow downward (e.g., as shown in FIG. 17A-C). The first channel may include a first opening 1781 in the bottom surface of housing 1708 and a second opening 1782 in the top surface of housing 1708. Gas may be received from the gas rod assembly via the first opening 1781. Gas may be supplied to an auxiliary component (e.g., a valve, regulator, filter, mass flow controller, etc.) mounted on top of sensor assembly 1700A via the second opening 1782. In some embodiments, the second channel may include a third opening 1783 in the top surface of housing 1708 to receive gas from the auxiliary component. The second channel may include a fourth opening in the bottom surface of the housing 1708 for supplying gas to the gas rod assembly. The second channel may form a return gas flow path to supply gas to a downstream component of the gas rod assembly. In some embodiments, the housing 1708 receives gas from an upstream component of the gas rod assembly. Similarly, in some embodiments, the housing 1708 is used to supply gas to a downstream component of the gas rod assembly.

[0256] In some embodiments, the first opening 1781, the second opening 1782, the third opening 1783, and / or the fourth opening 1784 include regions configured to receive sealing components. For example, the second opening 1782 may include a recess to receive an O-ring. The O-ring may be made of a material suitable for the interface between the sealing housing 1708 and the auxiliary component. In some embodiments, the second opening 1782 and the third opening 1783 are configured to receive end plugs (e.g., end plug 1786 of FIG. 17E, F) to guide gas from the first channel to the second channel. In some embodiments, the sealing portion of the first opening 1781 seals the interface between the housing 1708 and the substrate portion (e.g., the body) of the gas rod assembly.

[0257] In some embodiments, a filter / layer element 1722 is disposed in a channel of housing 1708. In some embodiments, the filter / layer element 1722 is a screen. The filter / layer element 1722 may be adhered to the inner surface of the first channel of housing 1708. In some embodiments, the filter / layer element 1722 may facilitate laminar airflow through the first channel and / or the second channel of housing 1708. As gas flows through the filter / layer element 1722, the airflow may be straightened (e.g., by means of an opening in the filter / layer element 1722). The straightened airflow may flow in a laminar manner.

[0258] In some embodiments, a recess is formed in the side surface of the housing 1708, into which a substrate 1702 (e.g., substrate 402, 502, 602, 702, 802, 902, or 1002) is mounted. The substrate 1702 may include electrical contact pads 1714 and electrical connections to one or more electrodes of the sensor device 300, which may be bonded to the substrate 1702 via any adhesive technique described herein. In some embodiments, the sensor device 300 may have been positioned and / or oriented relative to the substrate 1702 using any one or more alignment features and / or techniques described herein. In some embodiments, the sensor device 300 is disposed in a first channel. In some embodiments, the sensor device 300 is disposed in a second channel. Disposing the sensor device 300 in a second channel may facilitate the establishment of a laminar airflow through the housing 1708. In some embodiments, the sensor assembly 1700A includes two substrates 1702 and two sensor devices 300 (each sensor device is attached to one of the two substrates), each disposed in one of a first channel or a second channel. In some embodiments, the substrates 1702 are coupled to the housing via a flange / mate 1300. In embodiments, the flange / mate 1300 may be made of a stainless steel alloy or may be made of Kovar alloy. In some embodiments, the substrates 1702 are bonded to the flange / mate 1300 by welding or brazing, as described above. In some embodiments, the flange / mate 1300 is bonded to the housing 1708 by welding or brazing, as described above. In some embodiments, the substrates 1702 and the housing 1708 are coupled to form an hermetic seal. In some embodiments, a support ring 1703 (e.g., support ring 1500) is brazed or fused to the connector / flange 1300 to reduce mechanical and / or thermal stresses at one or more joints (e.g., fused joints, brazed joints, etc.) between the substrate 1702, the connector / flange 1300, and / or the housing 1708. In some embodiments, each of the connector / flange 1300 and the support ring 1703 may include a through-hole to receive the substrate 1702 (e.g., as shown in FIG. 17C). Similarly, the housing 1708 may include a hole to receive the substrate 1702 (e.g., as shown in FIG. 17C). In some embodiments, the sensor assembly 1700A includes a second sensor disposed within the housing. The second sensor may be attached to a second substrate. The second sensor may be selected from the group consisting of a temperature sensor, a flow sensor, or a pressure sensor. The second sensor may be configured to sense the conditions of gas flowing through either the first channel or the second channel. In some embodiments, a pressure sensor configured to sense gas pressure is disposed in a first channel, and a flow sensor (e.g., sensor device 300) is disposed in a second channel.

[0259] Figure 17E illustrates a perspective view of sensor assembly 1700B according to an embodiment of this disclosure. Figure 17F illustrates a front view of section GG in Figure 17F. In some embodiments, sensor assembly 1700B includes features similar to those of sensor 1700A as described above (e.g., housing 1708, substrate 1702, first opening 1781, sensor device 300, filter / layer element 1722, etc.). In some embodiments, sensor assembly 1700B includes an end plug 1786. End plug 1786 may be bonded to the top surface of housing 1708 (e.g., via fusion, brazing, welding, etc.). In some embodiments, end plug 1786 is bonded to a second opening 1782 and a third opening 1783 (e.g., the second and third openings of Figures 17A and D). In some embodiments, end plug 1786 plugs the second opening 1782 and the third opening 1783. The housing 1708 and / or end plug 1786 may include a channel (e.g., a third channel) connecting the first and second channels to direct airflow from the first channel to the second channel. In some embodiments, the housing 1708 of the sensor assembly 1700B is configured to receive gas from the gas rod assembly via a first opening 1781 and guide gas back to the gas rod assembly via a fourth opening 1784. In some embodiments, the sensor assembly 1700B includes a second sensor disposed within the housing. The second sensor may be selected from the group consisting of a temperature sensor, a flow sensor, or a pressure sensor. The second sensor may be configured to sense the conditions of gas flowing through either the first or second channel.

[0260] Figure 17G illustrates a cross-sectional view of the sensor assembly 1700C according to an embodiment of this disclosure. In some embodiments, the sensor assembly 1700C includes a pressure sensor 1792 disposed within a housing 1708. The pressure sensor 1792 can sense the pressure of gas flowing through one or more channels of the housing 1708. In some embodiments, the sensor assembly 1700C includes a sensor device 300 coupled to a substrate 1702. The sensor device 300 may be disposed in a gas return channel of the housing 1708. In some embodiments, the placement of the sensor device 300 may facilitate laminar airflow through the housing 1708.

[0261] Figure 17H ​​illustrates a schematic diagram of a sensor assembly (e.g., sensor assembly 1700A or 1700B) coupled to a gas rod assembly according to an embodiment of this disclosure. A plurality of gas rod assemblies can receive gas from a plurality of gas suppliers. For example, the processing apparatus can include different gas rod assemblies for each gas delivered to the process chamber. As shown, gas flows through the gas rod assembly from left to right. In some embodiments, gas rod assembly 1750 includes a mixing valve 1751, which may be a first component of gas rod assembly 1750. The mixing valve may include a manual valve and an automatically actuated valve (e.g., a pneumatic valve, an electric valve, etc.). Mixing valve 1751 can receive gas from a gas source (not shown). Mixing valve 1751 can direct gas to purge valve 1752 via one or more channels. Purge valve 1752 can be configured to purge gas rod assembly 1750. In some embodiments, gas rod assembly 1750 includes a regulator 1753. Regulator 1753 can receive gas from purge valve 1752. Regulator 1753 can regulate the gas flow rate through gas rod assembly 1750. In some embodiments, sensor assemblies 1700A, 1700B (e.g., sensor assembly 1700A or 1700B) can be coupled downstream of regulator 1753. Sensor assemblies 1700A, 1700B can be gas flow sensors for gas rod assembly 1750. In some embodiments, filter 1754 is connected to sensor assemblies 1700A, 1700B and receives airflow from sensor assemblies 1700A, 1700B (e.g., via a first channel as shown in Figures 17A-C). Filter 1754 can provide airflow back to sensor assemblies 1700A, 1700B (e.g., to a third opening 1783 as shown in Figures 17A-17D). In some embodiments, upstream valve 1755 can receive gas from sensor assemblies 1700A, 1700B and direct the airflow to mass flow controller 206. In some embodiments, sensor assemblies 1700A and 1700B act as mass flow controllers, and no additional mass flow controller is included in the gas rod assembly 1750. Mass flow controller 1756 and / or sensor assemblies 1700A and 1700B can control the gas flow rate through the gas rod assembly 1750. In some embodiments, downstream valve 1757 receives gas from the mass flow controller or other upstream components. Downstream valve 1757 can direct the gas to a gas destination (e.g., a processing chamber; not shown).

[0262] Although sensor assemblies 1700A and 1700B are described and illustrated as being positioned below filter 1754 along the airflow path, those skilled in the art will recognize that sensor assemblies 1700A and 1700B can alternatively be located anywhere along the airflow path of air bar assembly 1750. For example, sensor assemblies 1700A and 1700B can be located upstream and / or downstream of any component of the aforementioned air bar assembly. As another example, sensor assemblies 1700A and 1700B can be located below any of the aforementioned devices. Sensor assemblies 1700A and 1700B can receive airflow from upstream components of air bar assembly 1750 and direct the airflow to downstream components of air bar assembly 1750.

[0263] Figure 17I illustrates a perspective view of a sensor assembly (e.g., sensor assembly 1700A) coupled to a gas rod assembly 1750 according to an embodiment of this disclosure. A plurality of gas rod assemblies can receive gas from a plurality of gas suppliers. For example, the processing apparatus can include different gas rod assemblies for each gas delivered to the process chamber. As shown, gas flows through the gas rod assemblies from left to right.

[0264] In some embodiments, the gas rod assembly 1750 includes a base 1759. The gas rod assembly 1750 may receive gas (e.g., from a gas source) via a gas coupler 1758. In some embodiments, the gas rod assembly 1750 includes a mixing valve 1751, a purging valve 1752, a regulator 1753, a sensor assembly 1700A, a filter 1754, an upstream valve 1755, a mass flow controller 1756, and / or a downstream valve 1757. In some embodiments, each of the mixing valve 1751, purging valve 1752, regulator 1753, sensor assembly 1700A, filter 1754, upstream valve 1755, mass flow controller 1756, and / or downstream valve 1757 is coupled to the gas rod assembly base 1759. In some embodiments, the filter 1754 may be coupled to the top surface of the sensor assembly 1700A. As those skilled in the art will recognize, the sensor assembly 1700A may be coupled between the base 1759 and any of the mixing valve 1751, the purge valve 1752, the regulator 1753, the sensor assembly 1700A, the filter 1754, the upstream valve 1755, the mass flow controller 1756, and / or the downstream valve 1757. Similarly, in some embodiments, any of the mixing valve 1751, the purge valve 1752, the regulator 1753, the sensor assembly 1700A, the filter 1754, the upstream valve 1755, the mass flow controller 1756, and / or the downstream valve 1757 may be coupled to the top surface of the sensor assembly 1700A. In some embodiments, the sensor assembly 1700A is coupled between the base 1759 and a pressure sensor (not shown).

[0265] Figure 18 illustrates a schematic representation of a machine in an exemplary form of computer system 1800, wherein a set of instructions can be executed (e.g., to cause the machine to perform any or more methodologies discussed herein). In alternative embodiments, the machine may be connected to (e.g., networked) with other machines in a LAN, WAN, intranet, extranet, or internet. The machine may operate as a server or client machine in a client-server network environment, or as a peer machine in a peer-to-peer (or distributed) network environment. The machine may be a personal computer (PC), tablet PC, PDA, cellular phone, web appliance, server, network router, switch, or bridge, or any machine capable of executing a set of instructions (executed sequentially or otherwise) specifying the actions to be taken by the machine. Further, although only a single machine is shown, the term "machine" should also be considered as a collection of any machines that individually or collectively execute a set (or more) of instructions to perform any or more methodologies discussed herein. Some or all of the components of computer system 1800 may be utilized by or describe any of the electronic components described herein (e.g., any electronic components that are utilized by the operation of processing device 230 or combined chamber 101 or flow modulator 210).

[0266] An exemplary computer system 1800 includes a processing device (processor) 1802 communicating with each other via a bus 1810, main memory 1804 (e.g., ROM, flash memory, dynamic random access memory (DRAM) such as synchronous dynamic random access memory (SDRAM) or Rambus DRAM (RDRAM), static memory 1806 (e.g., flash memory, static random access memory (SRAM), etc.), and data storage device 1820.

[0267] Processor 1802 represents one or more general-purpose processing devices such as microprocessors, central processing units, etc. More specifically, processor 1802 may be a Complex Instruction Set Computing (CISC) microprocessor, a Reduced Instruction Set Computing (RISC) microprocessor, a Very Long Instruction Word (VLIW) microprocessor, or a processor implementing other instruction sets, or a combination of instruction sets. Processor 1802 may also be one or more special-purpose processing devices, such as application-specific integrated circuits (ASICs), field-programmable gate arrays (FPGAs), digital signal processors (DSPs), network processors, etc. Processor 1802 is configured to execute instruction 1840 to perform the operations and steps discussed herein.

[0268] Computer system 1800 may further include network interface device 1808. Computer system 1800 may also include video display unit 1812 (e.g., liquid crystal display (LCD) or cathode ray tube (CRT) or touch screen), digit input device 1814 (e.g., keyboard), cursor control device 1816 (e.g., mouse) and signal generating device 1822 (e.g., speaker).

[0269] Power supply device 1818 can monitor the power level of the battery used to power computer system 1800 or one or more components thereof. Power supply device 1818 can provide one or more interfaces to provide indications of power levels, the remaining time window before computer system 1800 or one or more components shut down, power consumption rate, indicators of whether the computer system is using external power or battery power, and other power-related information. In some embodiments, indications related to power supply device 1818 can be remotely accessed (e.g., via a network connection to a remote backup management module). In some embodiments, the battery used by power supply device 1818 can be a local or remote uninterruptible power supply (UPS) for computer system 1800. In this embodiment, power supply device 1818 can provide information about the power level of the UPS.

[0270] Data storage device 1820 may include computer-readable storage medium 1824 (e.g., non-transitory computer-readable storage medium) on which one or more sets of instructions 1840 (e.g., software) embodying any one or more methodologies or functions described herein are stored. These instructions 1840 may also reside wholly or at least partially within main memory 1804 and / or processor 1802 during execution by computer system 1800, which also constitute computer-readable storage medium. Instructions 1840 may further be transmitted or received on network 1830 via network interface device 1808. Although computer-readable storage medium 1824 is shown as a single medium in one exemplary embodiment, it should be understood that computer-readable storage medium 1824 may also include a single medium or multiple media (e.g., centralized or distributed databases and / or associated caches and servers) storing the set or multiple sets of instructions 1840.

[0271] Numerous details have been set forth in the foregoing description. However, it will be understood by those skilled in the art who benefit from this disclosure that it can be practiced without these specific details. While specific embodiments have been described herein, it should be understood that they are presented by way of example and not limitation. The breadth and scope of this application should not be limited to any of the embodiments described herein, but should be defined only by the claims and their equivalents set forth below and thereafter. In fact, various other embodiments of this disclosure and modifications thereof, in addition to those described herein, will become apparent to those skilled in the art from the foregoing description and drawings. Therefore, such other embodiments and modifications are intended to fall within the scope of this disclosure.

[0272] Referring to the accompanying drawings, which form part of this description, specific embodiments are illustrated in an illustrative manner. While these disclosed embodiments have been described in sufficient detail to enable those skilled in the art to practice them, it should be understood that these embodiments are not limiting, and therefore other embodiments may be used, and changes may be made to the disclosed embodiments without departing from the spirit and scope thereof. For example, the various blocks of the methods shown and described herein may not necessarily be performed in the order shown in some other embodiments. Furthermore, in some other embodiments, the disclosed methods may include more or fewer blocks than those described. As another example, some blocks described herein as individual blocks may be combined in some other embodiments. Conversely, something that may be described herein as a single block may be implemented in multiple blocks in some other embodiments. Furthermore, unless otherwise indicated, the conjunction "or" is intended to have an inclusive meaning herein where appropriate; that is, the statement "A, B, or C" is intended to include the possibilities of "A", "B", "C", "A and B", "B and C", "A and C", and "A, B, and C".

[0273] The terms "example" or "exemplary" are used herein to refer to something used as an example, instance, or illustration. Any pattern or design described herein as an "example" or "exemplary" is not necessarily to be construed as being better or more advantageous than other patterns or designs. Rather, the use of the terms "example" or "exemplary" is intended to present concepts in a specific manner. When the terms "about" or "approximately" are used herein, this term is intended to mean that the accuracy of the presented nominal values ​​is within ±10%.

[0274] Furthermore, unless otherwise specified or clearly indicated from the context that a singular form is involved, the article "a / an" as used herein and in the appended claims should generally be interpreted as meaning "one or more". Throughout this specification, references to "a / one embodiment," "some embodiments," or "certain embodiments" indicate that a particular feature, structure, or characteristic described in conjunction with those embodiments is included in at least one embodiment. Therefore, the phrases "a / one embodiment," "some embodiments," or "certain embodiments" appearing in various places throughout this specification do not necessarily refer to the same embodiment.

[0275] Some parts of the detailed description may be presented as algorithms and symbolic representations of operations performed on data bits within computer memory. These algorithmic descriptions and representations are the most effective way for those skilled in the field of data processing to communicate their work to others in the field. In this paper, generally speaking, an algorithm is considered a self-consistent sequence of steps that leads to a desired result. These steps are those that require physical manipulation of physical quantities. Typically, though not always, these quantities take the form of electrical or magnetic signals that can be stored, transmitted, combined, compared, or otherwise manipulated. It has proven convenient, sometimes primarily for common reasons, to refer to these signals as bits, values, elements, symbols, characters, items, numbers, or the like.

[0276] However, it should be remembered that all these and similar terms are to be associated with appropriate physical quantities and are merely convenient labels applied to those quantities. Unless otherwise specifically stated, it will be understood from the following discussion that throughout the description, discussions using terms such as “receive,” “capture,” “transmit,” “calculate,” “generate,” “process,” “reprocess,” “add,” “subtract,” “multiply,” “divide,” “optimize,” “calibrate,” “detect,” “execute,” “analyze,” “determine,” “empower,” “identify,” “modify,” “convert,” “apply,” “cause,” “store,” “compare,” or similar terms refer to the actions and processes of a computer system or similar electronic computing device that manipulate and transform data represented as physical (e.g., electronic) quantities in the computer system’s registers and memory into other data similarly represented as physical quantities in the computer system’s memory or registers or other such information storage, transmission, or display devices.

[0277] Furthermore, although this disclosure has been described herein in a specific context and for a specific purpose, those skilled in the art will recognize that its usefulness is not limited thereto, and that this disclosure can be advantageously implemented in any number of environments for any number of purposes. Therefore, the claims set forth below should be interpreted in accordance with the full breadth and spirit of this disclosure as described herein, and with the full range of equivalents to which such claims are entitled.

[0278] 100: System 101: Processing Chamber 102: Main body of the chamber 106: Internal volume 108: Sidewall 110: Bottom 112: Supply pipeline 116: Outer Lining 126: Exhaust port 128: Pump System 130: Showerhead 132: Gas delivery port 144:Substrate 148: Substrate support assembly 150: Electrostatic Chuck 152: Base 160: Gas source 170: Sensor assembly 200: Flow control device 210: Flow modulator 220: Sensor Component 222: Sensor devices 230: Processing equipment 240: Airflow Channel 242: Flow path 300: Sensor Devices 302: Supporting structure 304: Interface Area 306: Sensor Area 308: Sensing element 312: Cavity 314: Electrical contacts 400: Sensor Components 402:Substrate 404: Housing 414: Electrical contact pad 416: Conductor needle 420: Coating 460: Gas-facing surface 470: Relative surface 490: Seals 492: T-connector 500: Sensor Components 502:Substrate 504: Housing 514: Electrical contact pad 560: Gas-facing surface 570: Relative surface 580: O-ring 590: Seals 592: T-connector 600: Sensor Components 602:Substrate 604: Housing 614: Electrical contact pad 616: Conductor Needle 660: Gas-facing surface 670: Relative surface 690: Seals 700: Sensor Components 702:Substrate 704: Housing 714: Electrical contact pad 760: Gas-facing surface 770: Relative surface 800: Sensor Component 802:Substrate 814: Electrical contact pad 900: Sensor Component 902:Substrate 904: Housing 914: Electrical contact pad 960: Gas-facing surface 970: Relative surface 1000: Sensor Components 1002:Substrate 1004: Casing 1014: Electrical contact pad 1060: Gas-facing surface 1070: Relative surface 1100: Method 1110: Square 1120: Square 1130: Square 1140: Square 1200: Method 1202:Substrate 1203: Copper solder wire 1204: Casing 1210: Square 1214: Electrical contact pad 1220: Square 1230: Square 1240: Square 1250: Square 1260: Square 1278: Screw 1280: O-ring 1300: Adapter / Flange 1302:Substrate 1303: concave part 1399: Flange 1400: System 1401: Sensor Device 1402:Substrate 1403: Sensor Devices 1404:Substrate 1410: Protrusion 1412: Alignment Feature 1414: Alignment Feature 1416: Box 1417: Alignment Feature 1418: Alignment Feature 1420: concavity / notch 1422: Alignment Mark 1450: Airflow 1500: Support ring 1502:Substrate 1503: Sensor devices 1504: Vacuum Port 1512: Fixture 1514: Electrical contact pad 1515: Electrode 1516: Through hole 1517: Metallic adhesive layer 1518: Solder 1519: foil 1521: Metal Wire 1522: Fusion Node 1524: Radiation 1526: Laminated Layer 1602: Square 1604: Square 1606: Square 1608: Square 1612: Square 1614: Square 1616: Square 1618: Square 1620: Square 1622: Square 1632: Square 1634: Square 1636: Square 1638: Square 1640: Square 1642: Square 1652: Square 1654: Square 1656: Square 1658: Square 1662: Square 1664: Square 1666: Square 1668: Square 1670: Square 1672: Square 1674: Square 1702:Substrate 1703: Support ring 1708: Shell 1714: Electrical contact pad 1722: Filter / Laminated Element 1750: Gas spring assembly 1751: Mixing valve 1752: Purification valve 1753: Regulator 1754: Filter 1755: Upstream valve 1756: Mass Flow Controller 1757: Downstream valve 1758: Gas Coupler 1759: Base 1781: Opening 1782: Opening 1783: Opening 1784: Opening 1786: End plug 1792: Pressure Sensor 1800: Computer System 1802: Processing device / processor 1804: Main Memory 1806: Static Memory 1808: Network Interface Device 1810: Busbar 1812: Video display unit 1814: Digital input device 1816: Vernier control device 1818: Power Supply Equipment 1820: Data storage equipment 1822: Signal generating equipment 1824: Computer-readable storage media 1830: Internet 1840: Instructions 1002I: Internal Region 1002M: Middle Area 1002M1: Surface 1002M2: Surface 1002O: External Area 1004C: Tubular gas channel 1004M: Area 1080A: Slot 1201A: Sensor Assembly 1201B: Sensor assembly 1300A: Seals 1300B: Seals 1300C: Seals 1300D: Seals 1300S1: First side 1300S2: Second side 1501A: System 1501B: System 1501C: System 1501D: System 1501E: System 1501F: System 1501G: System 1600A: Method 1600B: Method 1600C: Method 1600D: Method 1600E: Method 1600F: Method 1700A: Sensor Assembly 1700B: Sensor Assembly 1700C: Sensor Component 402I: Internal Region 402M: Middle Area 402O: External Area 420A: Seals / Adhesives 420B: Seals / Adhesives 420C: Seals / Adhesives 420D: Seals / Adhesives 422A: Floor 422B: Layer 422C: Layer 422D: Layer 480A: Slot 480B: Slot 480C: Slot 502A: Floor 502B: Floor 502I: Internal Area 502M: Middle Area 502O: External Area 520A: Seals / Adhesives 520B: Seals / Adhesives 580A: Slot 580B: Slot 580C: Slot 602I: Internal Region 602M: Middle Area 602O: External Area 616H: Conductor pinhole 620A: Seals / Adhesives 620B: Seals / Adhesives 620D: Seals / Adhesives 620E: Seals 680A: Slot 680B: Slot 680C: Slot 702A: Floor 702B: Floor 702I: Internal Region 702M: Middle Area 702O: External Area 720A: Seals / Adhesives 720B: Seals / Adhesives 765A: First end 765B: Second end 780A: Slot 780B: Slot 802A: First end 802B: Second end 802I: Internal Region 802M1: Intermediate Area 802M2: Middle Area 802O1: External Region 802O2: External region 820A: Seals 820B: Seals 820C: Seals 902I: Internal Region 902M: Intermediate Area 902M1: Surface 902M2: Surface 902O: External Area 980A: Slot

[0279] Domestic storage information (please note in order of storage institution, date, and number) none

[0280] Overseas storage information (please note in the order of storage country, institution, date, and number) none

Claims

1. A sensor assembly, comprising: A substrate including an outer region, an inner region, and an intermediate region positioned between the outer region and the inner region, the substrate further including one or more electrical contact pads located at least on the inner region; a flange coupled to the substrate at the intermediate region or the outer region, wherein the flange is configured to couple to a housing to provide a hermetically sealed seal; and a sensor die bonded to the substrate at the inner region, wherein a metal adhesive bonds one or more electrodes of the sensor die to the one or more electrical contact pads, the metal adhesive comprising: a) platinum; or b) at least two metals, each metal being selected from the group consisting of tin, indium, copper, aluminum, and nickel.

2. The sensor assembly as claimed in claim 1, wherein the metal binder comprises one or more metal layers, the one or more metal layers comprising aluminum and nickel.

3. The sensor assembly as claimed in claim 1, wherein the one or more electrical contact pads and the one or more electrodes comprise platinum conductors.

4. The sensor assembly as claimed in claim 1, wherein the metal adhesive further comprises one or more metal adhesive layers on at least a portion of the one or more electrical contact pads and on at least a portion of the one or more electrodes.

5. The sensor assembly as claimed in claim 4, wherein the one or more metal adhesive layers comprise one or more of aluminum, an aluminum alloy, nickel, or a nickel alloy.

6. The sensor assembly as claimed in claim 2, wherein the metal binder comprises: A platinum fusion joint is located between the one or more electrodes and the one or more electrical contact pads, wherein each of the one or more electrodes includes a platinum wire, and a portion of the platinum wire covers and adheres to a corresponding electrical contact pad in the one or more electrical contact pads.

7. The sensor assembly as claimed in claim 1, further comprising an anti-corrosion coating deposited on at least a portion of the sensor assembly.

8. A method of manufacturing a sensor assembly, the method comprising the steps of: providing a substrate including an outer region, an inner region, and an intermediate region positioned between the outer region and the inner region, the substrate further including a first electrical contact pad and a second electrical contact pad at least located on the inner region; providing a sensor die including a first electrode and a second electrode, wherein the first electrode includes a first metal wire extending from the sensor die, and the second electrode includes a second metal wire extending from the sensor die; positioning the sensor die onto the inner region of the substrate such that a portion of the first metal wire covers the first electrical contact pad, and the second metal wire covers the second electrical contact pad; bonding the first metal wire to the first electrical contact pad by a first welding operation; bonding the second metal wire to the second electrical contact pad by a second welding operation; and coupling the substrate to a flange in the intermediate region or the outer region of the substrate, wherein the flange is configured to couple to a housing to provide a hermetically sealed connection.

9. The method of claim 8, wherein the first fusion operation and the second fusion operation comprise an electron beam fusion operation or a laser beam fusion operation.

10. The method of claim 8, wherein the first electrical contact pad and the second electrical contact pad comprise platinum, and wherein the first metal wire and the second metal wire comprise platinum.

11. The method of claim 8 further includes the step of: annealing at least the first metal wire and the second metal wire.

12. The method of claim 8, wherein the step of providing the sensor bare die including the first electrode and the second electrode comprises the steps of: bonding the first metal wire to the first electrode by a third welding operation; and bonding the second metal wire to the second electrode by a fourth welding operation.

13. The method of claim 12, wherein the third fusion operation and the fourth fusion operation comprise one of an electron beam fusion operation or a laser beam fusion operation.

14. The method of claim 8 further includes the step of depositing an anti-corrosion coating on at least a portion of the sensor assembly.

15. A method of manufacturing a sensor assembly, the method comprising the steps of: providing a substrate including an outer region, an inner region, and an intermediate region positioned between the outer region and the inner region, the substrate further including one or more electrical contact pads at least on the inner region; providing a sensor die including one or more electrodes; disposing a multilayer reactive foil onto at least one of: a) the one or more electrical contact pads of the substrate, or b) the one or more electrodes of the sensor die; positioning the sensor die on the inner region of the substrate such that the multilayer reactive foil is sandwiched between the one or more electrical contact pads and the one or more electrodes; igniting the multilayer reactive foil to form a metal bond between the one or more electrical contact pads of the substrate and the one or more electrodes of the sensor die; and coupling the substrate to a flange in the intermediate region or the outer region, wherein the flange is configured to couple to a housing to provide a hermetically sealed connection.

16. The method of claim 15, wherein the step of igniting the multilayer reactive foil comprises the steps of: applying a voltage to the multilayer reactive foil, wherein the multilayer reactive foil is shaped to conform to at least one of: a) a first shape of the one or more electrical contact pads, or b) a second shape of the one or more electrodes.

17. The method of claim 15, wherein the multilayer reactive foil comprises a plurality of alternating layers of nickel and aluminum.

18. The method of claim 15, wherein the one or more electrical contact pads and the one or more electrodes comprise platinum conductors, the method further comprising the steps of: depositing one or more metal adhesive layers on at least a portion of the one or more electrical contact pads and on at least a portion of the one or more electrodes.

19. The method of claim 18, wherein the one or more metal adhesive layers comprise one or more of aluminum, an aluminum alloy, nickel, or a nickel alloy.

20. The method of claim 15 further comprises the step of: depositing an anti-corrosion coating on at least an exposed portion of the metal binder.

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