Mobile sensor device for semiconductor manufacturing apparatus

Abstract

Systems and techniques are disclosed for obtaining multiple types of sensor information regarding operation of a semiconductor processing tool. Such systems and techniques may involve instrumented wafers including one or more different types of sensors including, for example, pressure sensors, oxygen (or other gas) sensors, humidity sensors, upward and / or outward imaging sensors or optical sensors, microphone sensors, and the like.

Description

Related Applications

[0001] The PCT application form is filed concurrently with this specification as a part of this application. Each application identified in the concurrently filed PCT application form to which this application claims the benefit or priority is incorporated herein by reference in its entirety and for all purposes. Background Art

[0002] At various points in time, semiconductor equipment may need to be calibrated or checked to optimize processing conditions and / or check one or more aspects of equipment status. In some cases, semiconductor equipment manufacturers and operators have used wafers equipped with accelerometers and downward-facing cameras to assist in wafer movement characterization and wafer centering or calibration operations. For example, such wafers are discussed in Patent Publication No. WO2021022291 (titled “INTEGRATED ADAPTIVE POSITIONING SYSTEMS AND ROUTINESFOR AUTOMATED WAFER-HANDLING ROBOT TEACH AND HEALTH CHECK”), the entire contents of which are hereby incorporated by reference herein. Summary of the invention

[0003] Details of one or more embodiments of the subject matter described in this specification are set forth in the accompanying drawings and the following description. Other features, aspects, and advantages will become apparent from the description, drawings, and claims. The following non-limiting implementations should be considered part of this disclosure; other implementations will be apparent from the disclosure and the drawings as a whole.

[0004] In some implementations, an apparatus for evaluating characteristics of a semiconductor processing tool or component may be provided. Such an apparatus may include: a base structure sized to be inserted through an opening of the semiconductor processing tool, the opening sized to receive a wafer for processing and transportable between at least two locations in the semiconductor processing tool by an object conveyor of the semiconductor processing tool. The base structure may have a first side configured to contact and be supported by a portion of the object conveyor and a second side facing in a direction opposite to the first side. The apparatus may also include one or more optical sensors, each optical sensor oriented so as to have an upward field of view when the base structure is oriented with the first side facing downward; a controller in communication with each of the one or more optical sensors; and a power source configured to provide power to at least the controller.

[0005] In some implementations, at least one of the one or more optical sensors can be an imaging sensor.

[0006] In some implementations, at least one of the one or more optical sensors can be coupled with corresponding one or more lenses that provide a field of view of at least 30° for the optical sensor.

[0007] In some implementations, the device can have two or more optical sensors that can be distributed on the device to have overlapping fields of view relative to a focal plane parallel to the second side and located at a first distance from the second side.

[0008] In some implementations, the first distance can be between 2 mm and 100 mm.

[0009] In some implementations, the area formed by the intersection of the focal plane and the field of view of the optical sensor may have a value of At least 15% of the total area of ​​the semiconductor processing tool, where d is the nominal wafer diameter of wafers that the semiconductor processing tool is configured to process.

[0010] In some implementations, there are multiple optical sensors and at least two of the optical sensors can be located at different distances from a center point of the base structure.

[0011] In some implementations, the device may further include a first support structure that is rotatably coupled to the base structure. The device may further include a first rotation driver that is configured to rotate the first support structure about a first rotation axis and relative to the base structure in response to receiving one or more first control signals. At least one of the one or more optical sensors may be directly or indirectly supported by the first support structure and may be located at a distance away from the first rotation axis in a direction perpendicular to the first rotation axis.

[0012] In some implementations, there can be multiple optical sensors supported directly or indirectly by the first support structure, and at least two of the optical sensors supported by the first support structure can be located at different distances from the first axis of rotation.

[0013] In some implementations, the first axis of rotation can be nominally centered on the base structure.

[0014] In some implementations, the first rotation axis can be offset from the center of the base structure.

[0015] In some implementations, the device may further include a second support structure rotatably coupled to the first support structure. The device may further include a second rotational driver configured to rotate the second support structure about a second rotational axis and relative to the first support structure in response to receiving one or more second control signals. The second support structure may be supported by the first support structure, the at least one of the one or more optical sensors may be supported by the second support structure, and the second rotational axis may be radially offset from the first rotational axis.

[0016] In some implementations, the maximum dimension of the base structure is 50% or less of a nominal wafer diameter of wafers that the semiconductor processing tool is configured to process.

[0017] In some implementations, the maximum dimension of the base structure can be 50% or less of 300 mm, and at least one of the one or more optical sensors can be disposed on the base structure at a position offset from a central axis of the base structure perpendicular to the second side.

[0018] In some implementations, there can be multiple optical sensors, and one of the optical sensors can be located near the central axis of the base structure.

[0019] In some implementations, the device may further include a first optical projection unit configured to project a first illumination pattern along a first axis. In such an implementation, the first axis may be at an oblique angle relative to the second side. The first axis may intersect a reference plane, the reference plane is parallel to the second side and offset from the second side by a first distance, the first side may be farther from the reference plane than the second side, and the one or more optical sensors may be positioned such that at least some positions where the reference plane may intersect the first illumination pattern are within a total field of view of the one or more optical sensors.

[0020] In some such implementations, the first illumination pattern may intersect the reference plane along a first line.

[0021] In some implementations, the device may further include a second optical projection unit. In such an implementation, the second optical projection unit may be configured to project a second illumination pattern along a second reference plane, the second reference plane being perpendicular to the second side and parallel to the first line, the first illumination pattern intersecting the reference plane along the first line, and the second illumination pattern may intersect the reference plane along a second line parallel to the first line.

[0022] In some implementations, the first illumination pattern can intersect the reference plane at a plurality of discrete locations distributed on the reference plane.

[0023] In some implementations, an apparatus for evaluating characteristics of a semiconductor processing tool or component may be provided. The apparatus may include a base structure sized to be inserted through an opening of a semiconductor processing tool, the opening sized to receive a wafer for processing and transportable between at least two locations in the semiconductor processing tool by an object conveyor of the semiconductor processing tool, a base structure having a first side configured to contact and be supported by a portion of the object conveyor and a second side facing in a direction opposite to the first side. The apparatus may also include one or more optical sensors, each optical sensor oriented to have a field of view facing outward relative to a central axis of the base structure. The apparatus may also include a controller in communication connection with each of the one or more optical sensors; and a power source configured to provide power to at least the controller.

[0024] In some implementations, there may be multiple optical sensors, and the optical sensors may be located near the outer edge of the base structure.

[0025] In some implementations, the optical sensors can be arranged in a circular array.

[0026] In some implementations, the fields of view of the optical sensors may overlap circumferentially at a radial distance from the central axis of the base structure, and the radial distance may be equal to the distance from the center of the base of the semiconductor processing tool to the inner wall surface structure of the semiconductor processing chamber of the semiconductor processing tool.

[0027] In some implementations, the device may further include a support structure rotatably coupled to the base structure. The device may also include a first rotation driver configured to rotate the support structure around a rotation axis in response to receiving one or more control signals, and at least one of the one or more optical sensors may be supported on the support structure.

[0028] In some implementations, the one or more optical sensors can be imaging sensors.

[0029] In some implementations, an apparatus for evaluating the characteristics of a semiconductor processing tool or component may be provided. The apparatus may include a base structure sized to be inserted through a door of a semiconductor processing tool and transported between at least two locations in the semiconductor processing tool by an object conveyor of the semiconductor processing tool, the base structure having a first side configured to contact and be supported by a portion of the object conveyor and a second side facing a direction opposite to the first side. The apparatus may also include one or more first ambient atmosphere sensors supported by the base structure, each of the first ambient atmosphere sensors being configured to measure a partial pressure of a first component of a target gas, a concentration of a first component in the target gas, a flow rate of the target gas, or any combination of two or more thereof, wherein the first component of the target gas is not water. The apparatus may also include a first controller. The first controller may be connected in communication with each of the one or more first ambient atmosphere sensors and may be supported by the base structure. The apparatus may also include a power source configured to provide power to at least the first controller.

[0030] In some implementations, the one or more first ambient atmospheric sensors can include at least one first ambient atmospheric sensor configured to measure a partial pressure of a first component in the target gas.

[0031] In some implementations, the one or more first ambient atmospheric sensors can include at least one first ambient atmospheric sensor configured to measure a concentration of a first component in a target gas.

[0032] In some implementations, the one or more first ambient atmosphere sensors can include at least one first ambient atmosphere sensor configured to measure a partial pressure of a first component and also measure a partial pressure of a second component in the target gas that is different from the first component.

[0033] In some implementations, the first component can be oxygen and the second component can be water.

[0034] In some implementations, the first component can be oxygen.

[0035] In some implementations, a system including one of the above-described devices may be provided. Such a system may include a semiconductor processing tool having one or more wafer handling robots and a semiconductor processing chamber. The system may also include a second controller, the second controller being communicatively coupled to the one or more wafer handling robots. The base structure may further support a first wireless communication interface, a second controller may be communicatively coupled to the second wireless communication interface, the second controller may be configured to communicate with the first controller via a wireless communication link using the first wireless communication interface and a second line communication interface, and the second controller may be configured to cause the one or more wafer handling robots to place the base structure in the semiconductor processing chamber and send one or more commands to the first controller to cause the first controller to obtain sensor readings from the one or more first ambient atmosphere sensors when the base structure is located in the semiconductor processing chamber.

[0036] In some implementations, the second controller may be further configured to cause a door of the semiconductor processing chamber to be sealed when the substrate structure is located within the semiconductor processing chamber.

[0037] In some implementations, the second controller can be further configured to control the one or more valves to shut off any gas flow into the semiconductor processing chamber through the one or more valves at least when the sensor readings are obtained.

[0038] In some implementations, the second controller can be further configured to control the one or more vacuum pumps or the one or more vacuum valves to stop any gas flow from the semiconductor processing chamber at least when the sensor reading is obtained.

[0039] In some implementations, there may be multiple first ambient atmosphere sensors at locations spaced apart from each other on the base structure, and the first controller or the second controller may be configured to identify a local peak measurement of a concentration or partial pressure of a first component of a target gas in a sensor reading, and the first controller or the second controller may be configured to determine which of the first ambient atmosphere sensors is associated with the local peak measurement, and determine a possible leak location in the semiconductor processing chamber based on the position of the first ambient atmosphere sensor associated with the local peak measurement relative to the semiconductor processing chamber.

[0040] In some implementations, the one or more first ambient atmosphere sensors can include at least one sensor configured to measure a flow rate of a target gas.

[0041] In some implementations, the at least one sensor configured to measure the flow rate of the target gas can be an anemometer.

[0042] In some implementations, the at least one sensor configured to measure the flow rate of the target gas can be a hot wire anemometer.

[0043] In some implementations, the at least one sensor configured to measure the flow rate of the target gas can be a plurality of sensors configured to measure the flow rate of the target gas.

[0044] In some implementations, the base structure can be circular and sized in diameter to match the diameter of a wafer that the semiconductor processing tool is configured to process, and two or more sensors configured to measure the flow rate of the target gas can be positioned near an outer edge of the base structure.

[0045] In some such implementations, the two or more sensors configured to measure the flow rate of the target gas may be located at evenly spaced locations along an outer edge of the base structure.

[0046] In some implementations, there may be at least first, second, and third sensors configured to measure the flow rate of the target gas, and the first, second, and third sensors configured to measure the flow rate of the target gas may be spaced 120° apart.

[0047] In some implementations, there may be at least first, second, third, and fourth sensors configured to measure the flow rate of the target gas, and the first, second, third, and fourth sensors configured to measure the flow rate of the target gas may be spaced 90° apart.

[0048] In some implementations, there may be one or more second ambient atmosphere sensors, each second ambient atmosphere sensor configured to measure a partial pressure of a first component of the target gas, a concentration of the first component in the target gas, or both.

[0049] In some implementations, the first component can be oxygen.

[0050] In some implementations, a system including the apparatus described above may be provided. The system may further include a semiconductor processing tool having an equipment front end module (EFEM) and one or more wafer handling robots located within the EFEM. The system may further include a second controller, the second controller being communicatively coupled to the one or more wafer handling robots. The base structure may further support a first wireless communication interface, the second controller may be communicatively coupled to the second wireless communication interface, the second controller may be configured to communicate with the first controller via a wireless communication link using the first wireless communication interface and a second wire communication interface, and the second controller may be configured to cause the one or more wafer handling robots to move the base structure between a plurality of measurement locations and send one or more commands to the first controller to cause the first controller to obtain sensor readings from the one or more first ambient atmosphere sensors associated with each measurement location and store them on one or more memory devices.

[0051] In some implementations, the semiconductor processing tool may further include a wafer buffer station located within or coupled to the EFEM, the wafer buffer station may have a plurality of wafer storage locations, and the plurality of measurement locations may include one or more measurement locations coinciding with one or more corresponding wafer storage locations.

[0052] In some implementations, the plurality of measurement locations can include one or more measurement locations within the interior of the EFEM.

[0053] In some embodiments, the semiconductor processing tool may further include a load port configured to receive a front opening pod (FOUP), and the plurality of measurement locations may include one or more measurement locations that coincide with locations within the FOUP when the FOUP is loaded onto the load port.

[0054] In some implementations, an apparatus for evaluating characteristics of a semiconductor processing tool or component may be provided. The apparatus may include a base structure sized to be inserted through a door of a semiconductor processing tool and transportable between at least two locations in the semiconductor processing tool by an object conveyor of the semiconductor processing tool, the base structure having a first side configured to contact and be supported by a portion of the object conveyor f and a second side facing a direction opposite to the first side. The apparatus may further include one or more microphone sensors supported by the base structure; a controller, wherein the controller is communicatively connected to each of the one or more sound sensors and supported by the base structure; and a power source configured to provide power to at least the controller.

[0055] In some implementations, the one or more sound sensors may be a plurality of microphone sensors disposed at different locations on the base structure.

[0056] In some implementations, the microphone sensors of the plurality of microphone sensors can be arranged in a circular array on the base structure.

[0057] In some implementations, the one or more microphone sensors may be omnidirectional microphone sensors.

[0058] In some implementations, the one or more microphone sensors may be directional microphone sensors.

[0059] In some implementations, the device may further include a support structure rotatably coupled to the base structure. The device may also include a rotational driver configured to rotate the support structure about a rotation axis in response to receiving one or more control signals, wherein at least one of the one or more microphone sensors is a directional microphone sensor and is supported by the support structure.

[0060] In some implementations, an apparatus for evaluating characteristics of a semiconductor processing tool or component may be provided. The apparatus may include a base structure sized to be inserted through a door of a semiconductor processing tool and transportable between at least two locations in the semiconductor processing tool by an object conveyor of the semiconductor processing tool, the base structure having a first side configured to contact and be supported by a portion of the object conveyor and a second side facing in a direction opposite to the first side. The apparatus may also include a plurality of different types of sensors supported by the base structure, the types of sensors including sensors configured to detect acoustic signals, sensors configured to detect optical phenomena, sensors configured to measure gas flow rates, and / or sensors configured to detect gas concentrations. The apparatus may also include a power source configured to provide power to at least the controller.

[0061] In some implementations, the device may further include an inductive charging coil coupled to the power source. BRIEF DESCRIPTION OF THE DRAWINGS

[0062] Various implementations disclosed herein are illustrated by way of example and not by way of limitation in the figures of the accompanying drawings in which like reference numerals refer to similar elements.

[0063] Figure 1 A schematic diagram of a wafer equipped with sensors is depicted.

[0064] Figure 2 An exemplary layout of an optical sensor of an exemplary sensor-equipped wafer is depicted.

[0065] Figure 3 An example of another layout of optical sensors of an exemplary sensor-equipped wafer is depicted.

[0066] Figure 4 An example of another layout of optical sensors of an exemplary sensor-equipped wafer is depicted.

[0067] Figure 5 Depicts the different rotation positions of Figure 4 An exemplary sensor-equipped wafer.

[0068] Figures 6-1 to 6-6 Depicted are different stages of operation of a wafer handling robot with a wafer equipped with sensors.

[0069] Figure 7 An exemplary sensor-equipped wafer is depicted with the optical sensor mounted facing upward on a rotatable support structure.

[0070] Figure 8-11 A diagram showing an exemplary wafer equipped with smaller diameter sensors during various stages of use.

[0071] Fig.12 Depicted Figure 2 An exemplary sensor-equipped wafer of but additionally comprising an illumination device.

[0072] Fig.13 Depicted Figure 4 An exemplary sensor-equipped wafer of but additionally comprising an illumination device.

[0073] Fig.14 An exemplary sensor-equipped wafer with an illumination pattern projection system is depicted.

[0074] Fig.15 Depicting an illumination pattern projection system for use with a sprinkler head having a non-flat underside Fig.14 An exemplary sensor-equipped wafer.

[0075] Fig.16 Depicted Fig.14 and Fig.15 A variation of the sensor-equipped wafer has a second illumination device configured to project a reference illumination pattern.

[0076] Fig.17 An example of a sensor-equipped wafer is depicted, having an optical sensor configured to have a radially outward-facing field of view.

[0077] Fig.18 An example of a sensor-equipped wafer having an optical sensor configured with a radially outward-facing field of view mounted to a rotatable support structure is depicted.

[0078] Fig.19A and 19B Another exemplary sensor-equipped wafer is depicted, wherein an upward-facing optical sensor is mounted on a rotatable support structure.

[0079] Fig. 20 An exemplary sensor-equipped wafer is depicted, wherein an upward-facing optical sensor is mounted on a rotatable support structure, which in turn is mounted on another rotatable support structure.

[0080] Figures 21A to 21E Depicted are views of a sensor-equipped wafer having multiple different sets of optical sensors.

[0081] Figures 22A to 27 C depicts a view of a sensor-equipped wafer with a steerable optical sensor.

[0082] Fig.23 An example of a sensor-equipped wafer having a substrate supporting a plurality of ambient atmosphere sensors is depicted.

[0083] Fig.24 Depicted with Fig.23 The same exemplary sensor-equipped wafer, but with different shaded areas showing different partial pressures resulting from leakage.

[0084] Fig.25 An exemplary semiconductor processing tool (or portion thereof) that may be configured to utilize a wafer equipped with a sensor is depicted.

[0085] Fig.26 A schematic diagram of a portion of a semiconductor processing tool is depicted.

[0086] Fig. 27 An example of a sensor-equipped wafer having a substrate supporting a plurality of microphone sensors is depicted.

[0087] Fig.28 An example of a sensor-equipped wafer having a substrate supporting a plurality of directional microphone sensors is depicted.

[0088] Fig.29 An example of a sensor-equipped wafer having a substrate supporting a rotatable support structure that supports a directional microphone sensor is depicted.

[0089] This article is attached Figure 1 The drawings are not generally drawn to scale unless indicated below. DETAILED DESCRIPTION

[0090] The inventors envision several different types of wafers or substrates equipped with sensors, which can be used to evaluate various aspects of the operational capabilities and / or performance of semiconductor processing tools. It should be understood that in many cases, the features of the various implementations discussed can be implemented together with the features of other implementations discussed herein, such as on a single wafer or substrate. It should be easily understood that since many of the implementations discussed herein can utilize relatively small sensors (compared to the size of the wafer supporting the sensor), it is feasible to include multiple different sensor systems on a common wafer or substrate. For the purposes of the present invention, in the context of the structure in which the sensors discussed herein can be installed, reference to a wafer should be understood to refer to a wafer or substrate, and the two terms can be used interchangeably herein. More generally, the sensors and related hardware discussed below about the wafer equipped with sensors (e.g., controllers, power supply sources, memory, etc. that can be docked with such sensors) can also be installed on structures other than wafers or substrates, such as on material sheets or plates, such as composite materials or carbon fibers. The shape of the structure to which such sensors and related hardware are mounted (either directly or indirectly) (also referred to herein as a "base structure") may be circular in shape (e.g., similar to a typical semiconductor wafer processed using a semiconductor processing tool, such as discussed below), or may be other shapes, such as polygonal, elliptical, circular, square, triangular, etc. Some such structures may also be generally flat in nature, but other such structures may be non-flat in nature, such as, for example, slightly domed. It should be understood that for the purposes of the present invention, references to a sensor-equipped wafer encompass similar devices that are not necessarily limited to using a wafer or substrate as a platform for attaching its sensors and other hardware (either directly or indirectly), such as devices using structures such as, but not limited to, the examples provided above. Therefore, references herein to a sensor-equipped wafer may be generally understood to refer more generally to a sensor-equipped device as well. Similarly, references herein to a substrate of such a sensor-equipped wafer may be understood to refer more generally to structures such as the above-mentioned structures as well.

[0091] The sensor-equipped devices discussed herein may generally be designed to include an independent power source, such as a rechargeable battery or other energy source. Such devices may also include one or more processors and one or more memory devices, and one or more communication interfaces, such as one or more wireless communication interfaces. The one or more processors may be configured to (e.g., via instructions stored on the one or more memory devices) obtain data from one or more sensors that can be operably connected to the one or more processors, and store the data in the one or more memory devices for subsequent transmission to, for example, an external controller, such as a controller of a semiconductor processing tool. Such communication may be performed, for example, via a physical connection to a chip (e.g., via a cable or connector connection) or via a wireless connection to a chip (e.g., via a Bluetooth or WiFi connection). It should be understood that the basic control and communication architecture can be used with a variety of different sensors and can be applied to any of the examples discussed herein.

[0092] The sensor-equipped wafers discussed herein may also be generally designed to be transported within and / or between semiconductor processing tools using the same equipment that is typically used to transport substrates or wafers during semiconductor processing operations. Thus, sensor-equipped wafers may generally be sized so as to have a similar size and shape to substrates or wafers that are typically processed using such equipment. For example, a sensor-equipped wafer used with a semiconductor processing tool for 300 mm diameter wafer processing operations may be sized to be 300 mm in diameter and to have a maximum thickness of no greater than, for example, 5 mm to 6 mm. Such sensor-equipped wafers may thus be transported between at least two locations within a semiconductor processing tool by a wafer handling robot, supported by shelves in a buffer (which may be sized to contact the edges of the wafer), loaded and transported by a front-opening wafer transport box (FOUP), transported through a slit valve aperture, a wafer transport channel, or other relatively wide and thin aperture (which may be provided to allow a wafer or substrate to be introduced into or removed from a semiconductor processing chamber and / or semiconductor processing tool). In some implementations, the substrate used in the sensor-equipped wafer may, for example, have the same diameter as a semiconductor wafer typically processed in a semiconductor processing tool (with which the sensor-equipped wafer is configured to be used). For example, if the semiconductor processing tool is configured to process 300 mm diameter wafers, the substrate of the sensor-equipped wafer may also be 300 mm diameter. The thickness of such a substrate may be similar to the thickness of such a wafer in some cases, for example, 0.75 mm to 1 mm. In other implementations, such a substrate may be larger and / or thicker than a wafer typically processed using a tool (with which the sensor-equipped wafer is expected to be used), for example, for a tool designed to process 300 mm wafers, the substrate may be on the order of 2 mm-4 mm thick or less and / or up to 400 mm in diameter, provided that the tool has clearance sufficient to allow such an oversized wafer to still be inserted and removed from one or more processing chambers of such a tool in a manner similar to the insertion or removal of a 300 mm wafer into or out of such a chamber or multiple chambers. For example, some semiconductor processing tools may be designed to allow wafers to be moved into and out of the tool, as well as between locations within the tool, using a "carrier ring," which is a generally thin, annular structure whose inner diameter is nominally the same size as the diameter of the wafer it is designed to carry. The carrier ring may have a number of features that support the wafer from below, such as protrusions that extend radially inward to a position within the edge of the wafer, or may have a rim along its inner circumference that has a diameter less than the diameter of the wafer, to enable the wafer to be brought from one location to another. In such a system, the semiconductor processing tool may have equipment that is configured to contact the carrier ring rather than directly contact the wafer. For example, lift pins or a wafer handling robot may be configured and / or arranged to contact the carrier ring rather than the wafer.In some instances, a carrier ring for a 300 mm diameter wafer may be up to 25 mm thick and 400 mm in diameter; it will be appreciated that some implementations of the sensor-equipped wafers discussed herein may therefore be configured to have a larger overall envelope than discussed above, e.g., up to 400 mm in diameter and 25 mm thick (thereby allowing the use of sensors of greater thickness).

[0093] It should also be understood that the sensor-equipped wafer may also have an overall height (including the substrate and components mounted thereto or supported therefrom) that is thicker than the height of a typical wafer to be processed. For example, if the void of the tool in which the sensor-equipped wafer is to be used supports the sensor-equipped wafer, such a sensor-equipped wafer may have an overall thickness of up to 25 mm.

[0094] It will also be appreciated that sensor-equipped wafers, such as those disclosed herein, may also be configured to be sufficiently large in size that they cannot be physically inserted into or withdrawn from a semiconductor processing tool or chamber through an interface through which the wafer to be processed is typically passed. For example, such oversized sensor-equipped wafers may be provided to such a semiconductor processing tool or chamber through a larger alternative interface than the interface through which the wafer to be processed passes. In some cases, the top plate of the chamber or tool may be removed to allow the sensor-equipped wafer to be placed in the chamber or tool, or the chamber or tool may have a resting position or resting point within it that can accommodate the sensor-equipped wafer (when not in use), thereby allowing the oversized sensor-equipped wafer to be used without having to insert the sensor-equipped wafer into the chamber or tool before each use and remove the sensor-equipped wafer from the chamber or tool after each use.

[0095] In some implementations discussed herein, one or more optical sensors (e.g., imaging sensors, photodetectors, etc.) may be located on a side of a substrate that is configured to face upward when placed in a semiconductor processing chamber. Such an upward arrangement may allow the optical sensor to obtain data about, for example, visible characteristics of a showerhead that is used to distribute gas to an entire wafer that may be loaded into a semiconductor processing chamber. Such data may, for example, provide insight into one or more aspects of the condition of a portion of a semiconductor processing chamber. For example, such data may be used to detect the presence of a deposited film on the underside of a showerhead or wear around a gas distribution port on the underside of a showerhead. A decision may then be made as to whether to clean and / or replace the showerhead based on the actual condition of the showerhead as evidenced by such data. In the event that a showerhead, for example, experiences a higher than expected rate of undesired deposition and / or wear on its underside, such data may allow an operator of a semiconductor processing tool to potentially perform a cleaning or replacement operation on the showerhead earlier than would normally be scheduled (e.g., according to a typical replacement or cleaning schedule). In the event that a showerhead experiences lower than expected undesirable deposition and / or wear rates, such as on its underside, such data may allow an operator of a semiconductor processing tool to potentially delay a scheduled cleaning or replacement operation for the showerhead.

[0096] In some implementations discussed herein, one or more optical sensors may be disposed on a substrate to have a field of view oriented along an axis parallel to or at least partially parallel to the substrate, for example, such that the one or more optical sensors may be used to obtain data regarding visible characteristics of, for example, a sidewall, a slit valve, or other component or portion of a semiconductor processing chamber of a semiconductor processing tool when the substrate is located within the semiconductor processing chamber. Such an apparatus may, for example, be used to obtain data regarding visible characteristics of such components or portions of a semiconductor processing chamber, such components or portions, for example, components or portions of the semiconductor processing chamber that are disposed radially outward from where a semiconductor wafer is typically located when semiconductor processing operations are performed within the semiconductor processing chamber. Such data may allow the condition of such components or portions of a semiconductor processing chamber to be evaluated for potential undesirable accumulation (e.g., film accumulation) and / or potential wear or damage to the component. This, in turn, may be used to determine whether and / or when it may be necessary to schedule a possible cleaning or component replacement operation.

[0097] In some implementations discussed herein, one or more humidity, gas level, temperature and / or airflow velocity sensors may be located on a substrate configured to be placed within a semiconductor processing chamber. Such sensors may then be used to obtain measurement data related to ambient atmospheric conditions near the substrate. Measurement data from some such sensors may be used, for example, to evaluate airflow on a substrate in a number of locations within an equipment front end module (EFEM), within a front opening wafer transfer box (FOUP), within a wafer buffer, within a load lock, or when transported by a wafer handling robot within an EFEM. In other instances, measurement data from some such sensors may be used to determine the level of a specific type of gas (e.g., oxygen) that may be present near a substrate under vacuum or near vacuum conditions within a semiconductor processing chamber. Such information may provide information about whether there is a potential leak of atmospheric air into a semiconductor processing chamber exceeding a specific limit. Such information may also be used in the context of nitrogen-purged EFEMs or other systems that operate at atmospheric pressure or near atmospheric pressure but have a composition significantly different from normal atmospheric air (e.g., a full nitrogen (or nearly full nitrogen) atmosphere). In such a case, such data may provide information about what the actual composition of such an atmosphere is.

[0098] Figure 1 A schematic diagram of an exemplary sensor-equipped wafer 100 is depicted showing various exemplary systems or components that may be included therein. As previously mentioned, the various sensors 120 included in the sensor-equipped wafer 100 may be communicatively coupled to a first controller 108, which may include one or more first processors 110 and one or more first memories or memory devices 112. The first controller 108 may also be electrically coupled to a power source 104, such as a battery, a capattery, or other power source. In some implementations, the power source 104 may be operably coupled to a charging feature utilizing electrical contact pins that are positioned to align with a charging feature located at, for example, a docking station for storing the sensor-equipped wafer 100 when the sensor-equipped wafer 100 is placed in the docking station. Figure 1 In the illustrated implementation, a wireless charging feature 106 is shown, which may be, for example, an inductive charging coil, such as a Qi-compatible inductive charging coil or other suitable wireless charging interface. In such a case, a docking station for storing the sensor-equipped wafer 100 may have a compatible wireless charging interface configured to charge the sensor-equipped wafer 100 when the sensor-equipped wafer 100 is placed therein. The various elements of the sensor-equipped wafer 100 may be mounted to or supported by the substrate 102 as previously described.

[0099] The first controller 108 may also be communicatively connected to a first wireless communication interface 114 (e.g., WiFi, Bluetooth, or other wireless communication interface) so that instructions and / or data may be sent from and / or to the first controller 108, and thus instructions and / or data may be sent from and / or to the sensor-equipped wafer 100. For example, a semiconductor processing tool docked with the sensor-equipped wafer 100 may include a second controller having one or more second processors and one or more second memories. The second controller may be communicatively connected to a second wireless communication interface, which in turn may be configured to dock with the first wireless communication interface of the sensor-equipped wafer. Therefore, the sensor-equipped wafer 100 may be able to wirelessly communicate with the semiconductor processing tool, thereby allowing information, instructions, and other data to be transmitted between the sensor-equipped wafer 100 and the semiconductor processing tool.

[0100] It should be understood that Figure 1 The basic architecture shown or other similar architectures may be connected to one or more sensors 120. The one or more sensors 120 may, for example, include multiple sensors, and in some implementations may include multiple sensors of multiple different types. It should be understood that the various components shown may be distributed as needed for a given layout or configuration of sensors to provide space for various individual sensors 120.

[0101] Figure 2 An exemplary layout of optical sensors of an exemplary sensor-equipped device or wafer is depicted, for example, a layout of a set of sensors 120 of a sensor-equipped wafer 100. Figure 2 As can be seen, a substrate 202 is provided; the substrate 202 may support various electronic systems, such as substrate 102 that may be similar to that which may be used to provide control, power, and communication functions to a plurality of sensors 120. The substrate 202 (as well as other substrates discussed herein) may generally be described as a nominally flat structure having a first side and a second side relative to the first side. The first side of the substrate 202 may, for example, be configured to be retained on an end effector of a wafer handling robot (used to transport wafers between locations within a semiconductor processing tool), while the second side may generally be oriented to face upward during transport within the semiconductor processing tool. Alternatively, the first side of the substrate 202 may be configured to be retained on some alternative type of object transfer system or device of the semiconductor processing tool, such as a rotary translator, an autonomous robot capable of freely navigating within a chamber or tool, and the like. As Figure 2As can be seen in FIG. 1 , optical sensors 222 (which are an example of sensors that may be included in the plurality of sensors 120) are distributed on the upper surface (second side) of substrate 202 such that each optical sensor 222 has a field of view that encompasses an area 223 on a reference plane (which is offset upwardly from substrate 202 by a distance X in a direction perpendicular to substrate 202). When a wafer equipped with sensors is positioned such that the first side of the wafer equipped with sensors is facing downward, optical sensors 222 may thus have a field of view that faces upward. When substrate 202 is supported in a semiconductor processing chamber with the top surface of substrate 202 facing upward and offset by a distance X from, for example, a showerhead of the semiconductor processing chamber (whose outer periphery is at Figure 2 When the lower side of the spray head 252 is shown as a dotted circle 252, most of the lower side of the spray head 252 will be within the field of view of the optical sensor 222. The distance X can be between 70 mm and 100 mm in some implementations, such as between 80 mm and 90 mm, such as about 85 mm.

[0102] This arrangement may allow the optical sensor 222 to obtain optical data about a large portion of the underside of the showerhead 252. Thus, for example, if the optical sensor 222 is an imaging sensor (e.g., a digital camera), the combined area of ​​the field of view on the reference plane may cover an area equal to 50%, 60%, 70%, 80%, or 90% or more (or even 100%) of the underside of the showerhead 252. If the fields of view 223 of such imaging sensors overlap at a focal plane parallel to and at a first distance from the second side of the substrate 202, the images obtained from these imaging sensors may be digitally composited to form a single larger image of the focal plane. For example, if the focal plane is at a distance X (e.g., coincident with the underside of the showerhead), such a composite image may depict the entire underside or nearly the entire underside of the showerhead 252. Even if the fields of view 223 do not necessarily overlap in such a focal plane, the discrete images may still provide information about the condition of the showerhead 252.

[0103] In some implementations, multiple optical sensors 222 may be provided such that the area resulting from the intersection of the focal plane and the field of view of the optical sensor 222 has an area (eg, ), where d is the nominal wafer diameter of the underside of the wafer (the semiconductor processing tool is configured to process the wafer).

[0104] like Figure 2As shown, the optical sensors 222 may be arranged in a triangular array, for example, with the centers of the optical sensors 222 located at the vertices of an equilateral triangle grid or lattice. This may be suitable for optical sensors where the optical sensors capture images of an entire circular field of view and may generally allow a minimum number of optical sensors to fully cover a given circular area or region. For optical sensors where the optical sensors capture images of rectangular sub-portions of a circular field of view, the optical sensors may be arranged in a rectangular, parallelogram, or other pattern and still allow a minimum number of optical sensors to be used to cover a given circular area.

[0105] In some implementations, such as Figure 3 As shown, additional optical sensors 222' may be placed in locations that are not aligned with any particular repeating pattern to provide additional imaging coverage and extend the synthetic field of view provided by optical sensor 222. As can be seen, such an arrangement (including placing optical sensor 222' near the outer periphery of substrate 202) may allow the synthetic field of view provided by field of view 223 to extend further beyond the footprint of substrate 202. This may allow optical sensors 222 and 222' to be used to obtain synthetic images of the underside of showerhead 252 directly above substrate 202 and peripheral areas of the underside of showerhead 252 that extend beyond the periphery of substrate 202.

[0106] The imaging sensors used in the sensor-equipped wafer may be, for example, similar to those used in smartphones and other miniature electronic devices. For example, camera modules including integrated optical lens systems (e.g., single-lens or multi-lens optical systems with a field of view of 30° or greater, such as 40° or greater, 50° or greater, 60° or greater, 70° or greater, 80° or greater, or even up to 180° or greater, and a depth of focus of the order of 2 mm to 100 mm) designed specifically for integration into smartphones and other portable electronic devices are widely available and may have a thickness of the order of 5 mm or less, allowing them to be integrated into the sensor-equipped wafer and still allowing the sensor-equipped wafer to have an overall maximum thickness of the order of 25 mm. Such a thickness allows the sensor-equipped wafer to be handled within a semiconductor processing tool in the same manner as a standard wafer to be processed without the risk of collision with components of the semiconductor processing chamber or other wafers that may be present within the semiconductor processing chamber. In some implementations, an imaging sensor used in a sensor-equipped wafer may be coupled with an optical lens system that provides a field of view between 30° and 180°.

[0107] It will be appreciated that if an imaging sensor is used as an optical sensor, such an imaging sensor may be used to obtain still image data or continuous image data, i.e., video data, which may depict the appearance of one or more components over time. For example, if a sensor-equipped wafer having one or more imaging sensors is oriented within a semiconductor processing chamber such that a slit valve or gate valve of the chamber is within the field of view of one or more such imaging sensors, the sensor-equipped wafer may be caused to obtain video footage from within the chamber with the slit valve or gate valve opened and / or closed, which may provide information about any potential mechanical issues with the operation of such components. In another example, such an imaging sensor may be used to obtain video footage of, for example, an edge ring positioned within a semiconductor processing chamber.

[0108] In some implementations, other arrangements of optical sensors may be used. Figure 4 An exemplary optical sensor arrangement is depicted, wherein the optical sensors 422 are arranged on only a portion of the substrate 402, e.g., spaced apart along a radius of the substrate 402. Alternatively, such optical sensors 422 may be located at different radial distances from the center of the substrate 402, but not necessarily along the same radius. In some such implementations, the optical sensors 422 may be arranged such that the center of each optical sensor 422 is located at a radial distance from the center of the substrate 402 that increases in steps of 8 mm to 12 mm, such as 10 mm steps. For example, for a sensor-equipped wafer having a substrate 402 of 300 mm diameter, there may be approximately 12 to 17 (e.g., 13 to 16 or 14 to 15) optical sensors 422 arranged such that each is disposed at a different radial distance from the center of the substrate 402, such that the radial distances are generally evenly distributed (e.g., each radial distance between X mm and Y mm is greater than the next highest radial distance, where X and Y are on the order of 8 mm to 13 mm). Such an arrangement reduces the amount of wafer area that may be required to accommodate the optical sensor 422, thereby leaving additional space to accommodate other components, such as Figure 1 Various systems discussed. A smaller number of optical sensors 422 may also result in reduced cost and reduced power consumption. In some embodiments, other types of sensors (eg, ambient atmosphere sensors or sound sensors) may occupy areas not occupied by optical sensors.

[0109] Such an arrangement may be applicable to semiconductor processing tools that do not require an image of a large portion of the underside of the showerhead 452. For example, if a showerhead in a given semiconductor tool is known to consistently have a circumferentially uniform or nearly circumferentially uniform layer of an undesirably deposited film that gradually accumulates on its underside over time, then one image or multiple images of the sensor-equipped wafer 400 along any given radius may be sufficient to obtain information about film deposition on the entire underside of the showerhead. Similarly, if a portion or location on the underside of a showerhead is known to have an accelerated level of deposition compared to other portions of the underside of the showerhead, then the sensor-equipped wafer 400 may be provided with one or more optical sensors, such as imaging sensors, that may be positioned to be placed directly below such location or locations or to image an area containing such location or locations.

[0110] It should be understood that Figure 4 The arrangement of optical sensors shown can also be used (in some cases) to obtain an image of a larger portion of the underside of the spray head than would be possible using Figure 4 The sensor-equipped wafer can image a larger Figure 5 As shown, it can be Figure 4 The sensor-equipped wafer is shown rotating relative to the showerhead 452 between using the optical sensor 422 to obtain data about the underside of the showerhead.

[0111] Figures 6-1 to 6-6 For example, several stages in an example of such a technique are depicted. Figure 6-1 4, a wafer handling robot 454 has been caused to extend into a semiconductor processing chamber 450 to retrieve a sensor-equipped wafer 400. Prior to such retrieval, the sensor-equipped wafer 400 has been caused to acquire data via an optical sensor 422 having a field of view 423 extending across a portion of the underside of a showerhead 452. The darker shaded portion of the showerhead 452 represents the area of ​​the showerhead 452 over which data has been acquired. The sensor-equipped wafer 400 may be supported on a pedestal (not shown) within the semiconductor processing chamber 450, for example, while acquiring data, and may then be lifted off the pedestal using a plurality of lift pins. With the sensor-equipped wafer 400 in a raised position, the wafer handling robot 454 may be caused to position a portion of its end effector 456 below the sensor-equipped wafer 400. The lift pins may then be retracted into the pedestal, thereby lowering the sensor-equipped wafer 400 onto the end effector 456.

[0112] exist Figure 6-24, the wafer handling robot 454 has been controlled to remove the sensor-equipped wafer 400 from the semiconductor processing chamber 450 and place the sensor-equipped wafer 400 on a rotatable wafer support 460 of an aligner 458 or other mechanism configured to allow the wafer placed thereon to be rotated and reoriented. As can be seen, the darker shaded area in the shape of three overlapping circles within the semiconductor processing chamber 450 still represents the area of ​​the showerhead 452 on which data has been obtained using the optical sensor 422.

[0113] exist Figure 6-3 , the wafer handling robot has been caused to withdraw the end effector 456 from under the sensor-equipped wafer 400 so that the sensor-equipped wafer 400 is supported only by the rotatable wafer support 460. For example, the rotatable wafer support 460 may have three pins extending vertically upward therefrom. The three pins may be used to support the sensor-equipped wafer 400 when the sensor-equipped wafer 400 is placed thereon, but may also be high enough so that the gap between the rotatable wafer support 460 and the underside of the sensor-equipped wafer 400 when the sensor-equipped wafer 400 is supported by the pins is sufficient to allow the wafer handling robot to move the end effector 456 up and down to contact or disengage with the sensor-equipped wafer 400 and to allow the end effector 456 to be withdrawn or inserted from the gap between the rotatable wafer support 460 and the sensor-equipped wafer 400.

[0114] exist Figure 6-4 4, the aligner 458 has been caused to rotate the rotatable wafer support 460 relative to the aligner 458 by a first angular amount, for example, 30°. As can be seen, this causes the optical sensor 422 to be repositioned so that when the wafer handling robot 454 is caused to move the end effector 456 back under the wafer 400 equipped with the sensor, as shown in FIG. Figure 6-5 As shown, the angular position of the optical sensor 422 relative to the end effector 456 is Figure 6-2 The optical sensor 422 is located at a different rotational orientation relative to the end effector 456 .

[0115] exist Figure 6-6 4, the wafer handling robot 454 has been caused to place the rotated sensor-equipped wafer 400 back into the semiconductor processing chamber 450. As can be seen, the optical sensor 422 has a field of view 423 that now covers a different area under the showerhead 452 (although the optical sensor 422 located at the center of the sensor-equipped wafer 400 will again image the same area). It should be understood that the above process can be repeated as needed. Figures 6-1 to 6-6The process shown can be used to obtain data from different regions, or all or substantially all, of the underside of the showerhead 452 from the optical sensor 422. For example, if the optical sensor 422 is an imaging sensor, the techniques discussed above can be used to obtain multiple sets of images of the sensor-equipped wafer 400 at different angular orientations to allow a single composite image of the underside of the showerhead 452 to be obtained. In some implementations, the sensor-equipped wafer 400 can be rotated by a large rotational amount between obtaining data from the one or more optical sensors, for example, a rotational amount large enough to allow gaps to exist between regions of the showerhead 452 for which data is obtained at the closest adjacent rotational positions.

[0116] In other implementations, multiple sets of optical sensors 422 are present on a sensor-equipped wafer so that data about a larger portion of the underside of showerhead 452 can be obtained at any given rotational position, thereby allowing sensor-equipped wafer 400 to be rotated fewer times and in a smaller total amount to obtain the desired data coverage of the underside of showerhead 452. For example, if Figure 6-1 to Figure 6-6 If the sensor-equipped wafer 400 instead has a row of optical sensors 422 extending across the entire diameter of the sensor-equipped wafer 400 (rather than just along its radius), the optical sensors 422 can be used to obtain data for a given portion of an annular area around the center-most field of view, the required rotation is Figures 6-1 to 6-6 Half of what is needed for the arrangement shown in .

[0117] It should be similarly understood that in order to use the above-described techniques, the optical sensor 422 need not be Figure 6-1 to Figure 6-6 In some implementations, it may be sufficient to have at least one optical sensor 422 whose field of view is offset from the center of the sensor-equipped wafer 400, so that when the sensor-equipped wafer 400 is angularly reoriented, the off-center optical sensor 422 rotates to a new rotational orientation and also rotates to a new XY position relative to a coordinate system (which is fixed relative to the showerhead 452). In some such implementations, there may be a plurality of optical sensors 422, each disposed at a different radial distance from the center of the sensor-equipped wafer 400, so that if the sensor-equipped wafer 400 were to be continuously rotated at a position below the showerhead 452, each such optical sensor 422 could be used to obtain data regarding visible characteristics of a different annular region on the underside of the showerhead 452.

[0118] It should be understood that in some implementations, the sensor-equipped wafer 400 may never actually be placed on a susceptor in a semiconductor processing chamber. For example, the wafer handling robot 454 may only support the sensor-equipped wafer 400 within the semiconductor processing chamber 450 at all times. Thus, the wafer handling robot 454 may position the sensor-equipped wafer 400 within the semiconductor processing chamber 450 at a location centered below the showerhead 452 and then cause the sensor-equipped wafer 400 to obtain data about visible features of the underside of the showerhead 452. The wafer handling robot 454 may then withdraw the sensor-equipped wafer 400 from the semiconductor processing chamber 450 and place it on a mechanism that can be used to rotate the sensor-equipped wafer, after which the wafer handling robot 454 may again retrieve the sensor-equipped wafer 400 and insert it into the semiconductor processing chamber 450. While the sensor-equipped wafer 400 is supported by the wafer handling robot 454 , the sensor-equipped wafer 400 may then be again manipulated to obtain further data regarding visible characteristics of different portions of the underside of the showerhead 452 .

[0119] It should be further understood that equipment other than the aligner 458 may be used in some implementations to perform rotation of the sensor-equipped wafer 400 between each data acquisition using the optical sensor 422. For example, in some implementations, a pedestal that may be used to support the sensor-equipped wafer 400 within the semiconductor processing chamber 450 may be provided with a rotation capability. In such an implementation, the pedestal may simply rotate and directly or indirectly support the sensor-equipped wafer 400. Such an implementation allows the sensor-equipped wafer 400 to be rotated relative to the showerhead 452 without having to move the sensor-equipped wafer 400 out of the semiconductor processing chamber 450 between rotation operations.

[0120] In another example, some wafer handling systems may have built-in wafer rotation capabilities. For example, in some multi-station semiconductor processing chambers, multiple (e.g., four) pedestals may be arranged in a circular array. Such semiconductor processing chambers may have a rotary indexer, such as an apparatus having a rotatable central hub with four equal-length rigid arms extending outwardly therefrom at equally spaced locations about the central hub. The wafer supports at the distal ends of the arms may be arranged so that each wafer supported thereby may be moved from a position centered above the center of a corresponding pedestal to a position centered above the center of a corresponding other pedestal in the semiconductor processing chamber 450.

[0121] In some rotary indexers, the rotary indexer may be equipped with a mechanism that allows the wafer support at the end of the rotary indexer arm to rotate relative to the arm, and the rotary indexer is otherwise fixed, for example. Thus, for example, the rotary indexer may be rotated to place one of its wafer supports below the sensor-equipped wafer 400 (which may be lifted off the base below it by, for example, lift pins to provide clearance for the wafer support to be so positioned). The sensor-equipped wafer 400 may then be placed on the wafer support and the wafer support may be rotated. The sensor-equipped wafer 400 may then be removed from the wafer support (e.g., by being lifted upward by lift pins in the base), and the indexer may be rotated so that the wafer support is removed from below the sensor-equipped wafer, thereby allowing the wafer to be lowered onto the base, for example, in a new rotational orientation. Such an indexer that is capable of rotating a wafer without rotating the indexer arm may in some cases be capable of rotating the wafer placed thereon by any angle between 0° and 90°, thereby allowing a variety of sensor-equipped wafer rotation options.

[0122] In a further implementation, if Figure 7 As shown, the sensor-equipped wafer itself may be equipped with the ability to rotate one or more optical sensors relative to its substrate. Figure 7 , a sensor-equipped wafer 700 is shown with a substrate 702. The substrate 702 has a support structure 764 rotatably mounted relative to the substrate 702. The substrate 702 may also support a rotational drive 766, such as a motor or other system, configured to rotate the support structure 764 relative to the substrate 702 by at least a first rotational amount. In some implementations, the first rotational amount may be an amount less than 360°, but in other implementations, the first rotational amount may be 360° (or greater than 360°).

[0123] One or more optical sensors 722 may be supported by the support structure 764 and oriented so that they have a field of view 723 pointing upward, for example, a field of view 723 along a direction generally parallel to an axis of rotation about which the support structure 764 is configured to rotate. At least one of the one or more optical sensors 722 may be supported by the support structure 764 at a position radially offset from the axis of rotation (for example, in a direction perpendicular to the axis of rotation) by at least some distance, for example, such that rotation of the support structure 764 causes the field of view 723 of at least one first optical sensor supported by the support structure 764 to rotate about the axis of rotation of the support structure 764. In some such implementations, there may be a plurality of such first optical sensors 722, each of which is disposed at a different distance from the axis of rotation, thereby allowing different annular regions of the underside of the spray head 752 to be imaged as the support structure 764 rotates. For example, in Figure 7In the embodiment, there are three such first optical sensors 722, which are arranged at three different distances from the rotation axis of the support structure 764. When the rotation drive 766 rotates the support structure 764, the first optical sensors 722 rotate around the rotation axis at different distances, so each has a field of view 723 that sweeps across one of several different annular areas on the underside of the spray head 750.

[0124] In some implementations, other electronics for the sensor-equipped wafer 700 (e.g., controllers, power sources, communication interfaces, etc.) may also be mounted to the support structure 764, so that all electronics rotate with the support structure 764. However, in other implementations, at least some of the other electrical components of the sensor-equipped wafer 700 may be mounted on the substrate 702. In such implementations, the one or more optical sensors 722 may be electrically connected to one or more electrical components mounted to the substrate 702, directly or indirectly, via, for example, a flexible cable. Alternatively, such electrical connections may be provided by conductive paths integrated into, for example, a bearing assembly (which is used to rotatably support the support structure)—for example, the electrical connection may be provided by a slip ring connection.

[0125] In such a sensor-equipped wafer, its controller may be controlled to provide one or more control signals to the rotational driver 766. The control signal may cause the rotational driver 766 to rotate, thereby causing the support structure 764 (and the optical sensor 722 mounted thereon) to rotate relative to the substrate 702. By such rotation, the optical sensor 722 may be moved between different rotational positions relative to the substrate 702, thereby allowing the optical sensor 722 to be used to collect data from different areas of the underside of the showerhead 752. In some implementations, such data may be continuously obtained from the optical sensor 722 while the support structure 764 is rotated, and the optical sensor 722 effectively acts as a rotating scanner. In other implementations, the optical sensor 722 may be caused to obtain such data between rotations of the support structure 764.

[0126] In some implementations, a sensor-equipped wafer configured for use in a particular semiconductor processing tool may include a substrate having a size that is smaller than the size of the wafer that the semiconductor processing tool is configured to process. For example, if the semiconductor processing tool is configured to process 300 mm wafers, such a sensor-equipped wafer may be, for example, 200 mm or less, 150 mm or less, or 100 mm or less in diameter. Such a sensor-equipped wafer may, for example, have a substrate having a diameter that is 60% or less (e.g., 50%) of the nominal wafer diameter of wafers typically processed in a semiconductor processing chamber, such that such a sensor-equipped wafer is intended for use internally. For example, in some instances, an end effector that supports a semiconductor wafer during a wafer transport operation in a semiconductor processing tool (and which will be used to transport a sensor-equipped wafer) may contact a 300 mm wafer with a diameter contact area that spans 50 mm, in which case the diameter of the sensor-equipped wafer may be as low as 17% of the nominal diameter of a wafer typically processed in a semiconductor processing chamber and still be supported by the end effector.

[0127] In such an implementation, the smaller substrate size would limit the space available to support the optical sensors - however, such a sensor-equipped wafer may offer more positional flexibility due to its smaller size. Figures 8 to 11 A diagram of a wafer equipped with smaller diameter sensors is shown. Figures 8 to 11 8, a semiconductor processing chamber 850 including a showerhead 852 is shown. A wafer footprint 872 is shown below the showerhead 852, which represents a typical position / footprint of a semiconductor wafer within a semiconductor processing chamber during wafer processing operations. A wafer handling robot 854 is shown having an end effector 856 for supporting a sensor-equipped wafer 800. The sensor-equipped wafer 800 has a substrate 802 supporting a number of optical sensors 822 having an upward field of view 823. In this example, there are seven optical sensors 822, but it should be understood that more or fewer optical sensors may also be used.

[0128] It should be noted that substrate 802 has a smaller diameter than the diameter of wafers typically processed within semiconductor processing chamber 850, as indicated by the size difference between wafer footprint 872 and substrate 802. This allows sensor-equipped wafer 800 to be moved between different locations within a semiconductor processing chamber, such as Figures 8 to 11 As shown, data can be obtained about visible characteristics of different portions of the showerhead 852. Such an arrangement can allow such a sensor-equipped wafer to obtain optical data of a larger area of ​​the showerhead that is much larger than the total field of view of the optical sensors contained on such a sensor-equipped wafer.

[0129] It should be understood that in such implementations, the sensor-equipped wafer may have more or fewer optical sensors than the seven depicted. The sensor-equipped wafer may even have only a single optical sensor (or a single optical sensor of a particular type of optical sensor). In some implementations, a controller of a semiconductor processing tool (e.g., having one or more processors and one or more memory devices) may control a wafer handling robot, through computer executable instructions stored therein, to retrieve such a sensor-equipped wafer, for example, from a storage location or other location outside of a semiconductor processing chamber of the semiconductor processing tool, and then insert it into the semiconductor processing chamber of the semiconductor processing tool. The instructions may further cause the wafer handling robot to move the sensor-equipped wafer between different locations within the semiconductor processing chamber and send one or more commands to the sensor-equipped wafer so that the sensor-equipped wafer obtains data about the visible characteristics of the underside of the showerhead at each such location. Such optical data may then be retrieved from the sensor-equipped wafer and analyzed, for example, to generate a composite image of the underside of the showerhead.

[0130] As previously described, the optical sensor used may be, for example, an imaging sensor, such as a charge coupled device (CCD) or other pixel-based imaging sensor. In some cases, such an optical sensor may be used without an external illumination source. In other implementations, a sensor-equipped wafer having one or more optical sensors may also include one or more lighting devices or systems that can be configured to provide a desired form of illumination. In some such examples, an illumination source (e.g., a light source) may be used that provides diffuse, relatively uniform light on a surface from which data will be acquired using an optical sensor. For example, one or more light emitting diodes, electroluminescent panels, or other light emitting structures may be mounted to a side of the sensor-equipped wafer 400 facing the showerhead 452, so that the sensor-equipped wafer 400 may direct light (e.g., light in a specific spectrum or light in a broad spectrum (e.g., white light)) upward toward the lower side of the showerhead 452. In some such implementations, a diffuse material (e.g., a diffuse light-transmitting medium) may be placed on the light emitting structure to more evenly distribute the illumination and prevent or mitigate potential specular reflections that may blur the visible features expected to be captured by the optical sensor.

[0131] Fig.12 and 13 Describes something similar to Figure 2-5 Sensor-equipped wafer examples of those discussed, but with the addition of an illumination source that can be used to illuminate the surface from which the optical sensor (imaging sensor) is configured to acquire optical data. For example, Fig.12 Depicted Figure 2The sensor-equipped wafer 200 is similar to the sensor-equipped wafer 200, but with the addition of illumination devices 224 arranged on the upper surface of the substrate 202. The illumination devices 224 are electroluminescent panels or LEDs in this example that are generally triangular in shape and arranged so that the corners of each triangular panel are generally adjacent to different ones of the optical sensors 222. Such illumination devices 224 can be illuminated to direct light toward the surface of any object located above the sensor-equipped wafer (e.g., underside of the showerhead 252). As described above, the illumination devices 224 may in some cases include a layer of diffusing material that is used to diffuse the light emitted from the illumination devices 224, thereby reducing or preventing specular reflections of the surface being imaged.

[0132] Fig.13 Depicted Figure 4 The sensor-equipped wafer 400 is shown in FIG. 1 , but with the addition of lighting devices 424. The lighting devices 424 are rectangular electroluminescent panels or LEDs in this example, which are disposed on either side of, between, and at both ends of the three optical sensors 422 shown. Such lighting devices may in some examples include a layer of diffuser material, such as Fig.12 as shown in the example.

[0133] In some implementations of a sensor-equipped wafer with an illumination source, an illumination source may be provided that projects a structured image along an axis that is at an oblique angle relative to the substrate 402 of the sensor-equipped wafer 4002, for example, at an oblique angle relative to the second side of the substrate 402 (the first side of the substrate 402 faces and / or contacts the base, while the second side of the substrate 402 faces upward toward the showerhead). For example, an illumination source may be used that projects a straight line that is parallel to and coincides with a plane that is at an oblique angle relative to the substrate 402. Such an illumination source may be provided, for example, using a laser diode coupled to a diffractive optical element that disperses collimated light generated by the laser diode into a line. When such an illumination pattern is projected onto a reference plane that is parallel to the substrate 402 (and farther from the first side of the substrate than the second side of the substrate), the projected light will intersect the reference plane along a line. Thus, if the reference plane is, for example, the underside of the showerhead 452 and the underside of the showerhead 452 is flat and parallel to the substrate 402, the light irradiated to the underside of the showerhead 452 will form a straight line. Fig.14 The schematic is depicted.

[0134] Fig.141400 is shown at the top in a side view of a sensor equipped wafer 1400 supported by a pedestal 1462 below a showerhead 1452 and at the bottom in a plan view of the same structure. The sensor equipped wafer 1400 includes a substrate 1402 on which a plurality of optical sensors 1422 arranged along a diameter of the sensor equipped wafer 1400 are mounted. An illumination device 1424 is also supported by the substrate 1402, which in this example is a laser diode coupled to a diffractive optical element that expands a collimated beam emitted by the laser diode into a two-dimensional fan beam 1426. The fan beam is parallel to and coincident with a plane perpendicular to the page, i.e., parallel to the Y axis of the coordinate system shown, and parallel to the dashed line indicating the beam 1426.

[0135] When the bottom side of the showerhead 452 is flat and completely parallel to the substrate 1402, as shown in FIG. Fig.14 As shown, the fan-shaped beam will produce a straight-line illumination pattern 1428. The optical sensors 1422, which may be imaging sensors, may be disposed on the substrate 1402 such that the illumination pattern 1428 is within the collective field of view 1423 of the optical sensors 1422. Thus, if an image of the underside of the showerhead 1452 is acquired using the optical sensors 1422 when the illumination pattern 1428 is projected onto the underside of the showerhead 1452, the resulting composite image will display the illumination pattern 1428 as a straight line.

[0136] However, if the underside of the nozzle 1452 where the beam falls is not flat due to deposition on the underside of the nozzle 1452, the fan-shaped beam will illuminate the underside of the nozzle and the Fig.14 For example, in addition to a slight bulge on the underside of the nozzle 1452, Fig.15 and Fig.14 The same may be caused, for example, by the deposition on the underside of the showerhead 1452 being thickest near the center of the showerhead and decreasing in thickness near the edge of the showerhead 1452 .

[0137] Due to the protrusion, the light beam 1426 shining on the lower side of the nozzle 1452 shines on the same direction as in the ideal case (such as Fig.14 This is because the beam strikes the underside of the printhead at a small angle; any change in the height at which the beam strikes the underside of the printhead will generally result in a lateral (XY) shift in the intersection point location. Fig.15 In the case of the shallow dome-shaped profile of the underside of the nozzle 1452 shown, as shown Fig.14 The previously straight illumination pattern shown instead presents a slightly curved illumination pattern 1428'. The maximum amount of deviation from the straight illumination pattern 1428 to the curved illumination pattern 1428' represents the maximum amount of non-uniformity in the thickness of the deposited material on the underside of the showerhead 1452.

[0138] In some implementations, a second illumination device can be used to provide a second illumination pattern. The second illumination pattern can be projected onto the underside of the showerhead 1452 in a manner that minimizes or eliminates the amount of deformation that the second illumination pattern may experience when projected onto the underside of the showerhead 1452 when the underside is not flat and / or parallel to the substrate 1402.

[0139] Fig.16 Depicts the following Fig.15 Elements identical to those depicted: Sensor-equipped wafer 1400 further includes a second illumination device 1424' configured to project a reference illumination pattern 1430 onto the underside of showerhead 1452 in a manner that substantially frees it from distortion similar to that experienced by illumination pattern 1428'. For example, reference illumination pattern 1430 may resemble a fan beam from a laser diode, but may be projected such that the fan beam is perpendicular to substrate 1402 and parallel to a line formed by the intersection of illumination pattern 1428 with a plane (e.g., a reference plane parallel to substrate 1402). Thus, the fan beam forming reference illumination pattern 1430 may actually be a vertical plane that intersects the underside of showerhead 1452, but without any offset in the position of the intersection in a direction perpendicular to the vertical plane. Thus, reference illumination pattern 1430 will remain linear and may provide a basis for comparison with illumination pattern 1428'. As can be seen, optical sensor 1422 can be configured to simultaneously image both reference illumination pattern 1430 and illumination pattern 1428. If illumination pattern 1428' is linear (e.g., Fig.14 1428), the illumination pattern 1428 and the reference illumination pattern 1430 may be parallel or even co-linear, depending on the positioning of the two patterns.

[0140] It should be appreciated that illumination pattern 1428 may take any of a variety of different forms including, for example, a rectangular grid pattern, a rectangular array of "+" symbols, a rectangular array of dots, a pattern of concentric circles, a rectangular pattern of circles, etc. The illumination pattern may also be an arrangement of non-repeating shapes. Figures 14 to 16 The single line pattern used in provides an easily understood example, but it is apparent that any illumination pattern projected onto the underside of the showerhead 1452, typically at an oblique angle compared to a flat showerhead underside, will be deformed when projected onto the non-flat showerhead underside, and the amount of such deformation imaged by the optical sensor 1422 located substantially directly below the location where the illumination pattern impinges on the underside of the showerhead 1452 will provide information about the deviation of the showerhead underside from a completely flat surface parallel to the substrate 1402.

[0141] It should also be appreciated that determining the degree of deviation in a given illumination pattern due to the non-planar underside of showerhead 1452 may be accomplished by a variety of mechanisms. For example, an illumination pattern recorded by an optical sensor of sensor-equipped wafer 1400 may be compared to a known or expected illumination pattern, e.g., if it is known that illumination pattern 1428 should produce a straight line, then the illumination pattern recorded by the optical sensor may be evaluated to determine how far it deviates from the straight line.

[0142] In other implementations, as discussed above, a reference illumination pattern that is not deformed (in at least one direction) due to changes in the underside profile of showerhead 1452 may also be projected onto the underside of showerhead 1452, such that optical sensor 1422 may be used to obtain image data for both illumination pattern 1428 and reference illumination pattern 1430, thereby allowing a direct comparison between the two imaged patterns. It should be understood that reference illumination pattern 1430 and illumination pattern 1428 may be projected onto the underside of showerhead 1452 at different, non-overlapping times and separate images may be taken for each pattern. If the wafer on which the sensor is mounted does not move between taking such pictures, then using the two images to assess the amount of deviation between the two patterns may be relatively simple.

[0143] In still further implementations, a sensor-equipped wafer may be used to obtain an initial calibration image of the underside of showerhead 1452 while an illumination pattern is projected thereon. Such a calibration image may be obtained while showerhead 1452 is still in a pristine state, e.g., before showerhead 1452 is first exposed to a gas that may deposit a film on its underside, thereby potentially changing the profile of the underside of showerhead 1452. This calibration image may then be retained and compared to future images of such an illumination pattern projected onto the underside of the showerhead with the sensor-equipped wafer positioned at the same position and orientation within a semiconductor processing chamber. Deviations between the illumination pattern shown in the calibration image and the illumination pattern shown in subsequent images (e.g., obtained after the underside of the showerhead has experienced a change in the underside profile, possibly due to unintended deposition) may then be identified and quantified to provide an indication of non-uniformity of the underside of the showerhead.

[0144] In some implementations, one or more optical sensors may be disposed on a sensor-equipped wafer and oriented such that the one or more optical sensors have a field of view directed radially outward toward, for example, a semiconductor processing chamber sidewall or toward a component located in a semiconductor processing chamber sidewall. Fig.17 An example of a sensor-equipped wafer having an optical sensor configured to have a radially outward field of view is depicted. Fig.17, a substrate 1702 for a sensor-equipped wafer 1700 is shown. A plurality of optical sensors 1722 are disposed at spaced locations along the outer periphery of the substrate 1702 and are oriented such that they have fields of view 1723 directed radially outward from the substrate 1702. In the depicted example, the optical sensors 1722 (which may be imaging sensors) are spaced such that they have circumferentially overlapping fields of view 1723 at a given radial distance from the center of the sensor-equipped wafer 1700. For example, the fields of view 1723 may circumferentially overlap at a radial distance from the center of the sensor-equipped wafer 1700 that is equal to the distance between the inner wall surface of a semiconductor processing chamber 1750 in which the sensor-equipped wafer 1700 is disposed and the center of the sensor-equipped wafer 1700 (or the distance between the inner wall surface and the central axis of a susceptor on which the sensor-equipped wafer 1700 is disposed when placed in the semiconductor processing chamber).

[0145] When arranged in such a manner, data (e.g., image data) obtained from optical sensor 1722 may be processed to provide a single data set representing optical data obtained from the entire perimeter of a portion of one or more interior walls of a semiconductor processing chamber (or other structure, such as a slit valve through which a wafer may pass for introduction / removal from a semiconductor processing chamber). Thus, for example, such a sensor-equipped wafer may be used to obtain a single synthetic panoramic image of the interior wall surface of semiconductor processing chamber 1750.

[0146] It should also be understood that the spacing between the optical sensors 1722 may be large enough so that some or all of the fields of view 1723 of the optical sensors 1722 do not overlap in such a manner, and therefore there may be areas of the inner wall surface of the semiconductor processing chamber 1750 for which data is not obtained from the optical sensors 1722. In some implementations, the optical sensors 1722 may be placed at one or more locations, and then the sensor-equipped wafer 1700 is placed in the semiconductor processing chamber 1750 in a predefined orientation, aligned with and oriented toward the one or more locations for which data is to be obtained from the optical sensors 1722. Such locations may include, for example, locations where it is known or expected that undesirable increases in deposition levels (or other semiconductor processing byproducts or effects) may occur, or areas where components that are particularly sensitive to such deposition or other processing operations may exist. For example, one or more such optical sensors 1722 may be arranged to be located at a position along the outer periphery of the sensor-equipped wafer, which is located near a slit valve with a field of view 1723 oriented toward the slit valve, which is used to seal a wafer transfer channel through which a sensor-equipped wafer can pass when it is introduced into the semiconductor processing chamber 1750. Such a slit valve may be susceptible to potential damage, for example, caused by undesirable deposition or etching or by normal wear and tear. For example, such a slit valve may have an elastomeric seal that is used to seal the slit valve door of the semiconductor processing chamber 1750 to provide an airtight interface. Such a seal may be subject to wear each time the slit valve is opened or closed. If a sensor-equipped wafer with an optical sensor 1722 (e.g., an image sensor) is provided as suggested, such an optical sensor 1722 can be used to obtain data about the slit valve, such as one or more images. Such data can allow the condition of the seal to be evaluated without opening the semiconductor processing chamber or disassembling the slit valve.

[0147] In some implementations, the sensor-equipped wafer may be provided with one or more radially outwardly facing optical sensors mounted to a support structure that is rotatably mounted relative to the substrate; Fig.18 An example of such a sensor-equipped wafer is shown in .

[0148] exist Fig.18, a sensor-equipped wafer 1800 is shown with a substrate 1802. The substrate 1802 has a support structure 1864 rotatably mounted relative to the substrate 1802. The substrate 1802 may also support a rotational drive 1866, such as a motor or other system, which is configured to rotate the support structure 1864 relative to the substrate 1802 at least a first rotational amount. As shown, the rotational drive 1866 has a gear that meshes with gear teeth along the exterior of the support structure 1864, but alternative implementations may use a linkage-based mechanism (e.g., a crank arm coupled to a linear actuator), a friction drive mechanism (e.g., a wheel with an outer edge of an elastomeric body pressed against the exterior of the support structure 1864), etc. In some implementations, the first rotational amount may be an amount less than 360°, but in other implementations, the first rotational amount may be 360° (or greater than 360°).

[0149] One or more optical sensors 1822 may be supported by the support structure 1864 and oriented so that they have a field of view 1823 directed, for example, radially outward from the center of rotation of the support structure 1864. In some implementations, other electronics for the sensor-equipped wafer 1800 (e.g., controllers, power sources, communication interfaces, etc.) may also be mounted to the support structure 1864 so that all electronics rotate with the support structure 1864. However, in other implementations, at least some of the other electrical components of the sensor-equipped wafer 1800 may be mounted on the substrate 1802. In such implementations, the one or more optical sensors 1822 may be electrically connected to the one or more electrical components mounted to the substrate 1802, directly or indirectly, via, for example, a flexible cable. Alternatively, such electrical connection may be provided by a conductive path integrated into, for example, a bearing assembly (for rotatably supporting the support structure)—for example, the electrical connection may be provided by a slip ring connection.

[0150] In such a sensor-equipped wafer, its controller may be controlled to provide one or more control signals to the rotation driver 1866. The control signal may cause the rotation driver 1866 to rotate, thereby causing the support structure 1864 (and the optical sensor 1822 mounted thereon) to rotate relative to the substrate 1802. By such rotation, the optical sensor 1822 may be moved between different rotational positions relative to the substrate 1802, thereby allowing the optical sensor 1822 to be used to collect data of an area of ​​the inner wall of the semiconductor processing chamber 1850 at different rotational positions. In some implementations, such data may be continuously obtained from the optical sensor 1822 while the support structure 1864 is rotated, and the optical sensor 1822 actually acts as a rotating scanner. In other implementations, the optical sensor 1822 may be caused to obtain such data between rotations of the support structure 1864.

[0151] It should also be understood that a sensor-equipped wafer having a support structure configured to be rotatable relative to a substrate of the sensor-equipped wafer, e.g., as described above, can also be used with an optical sensor having an upward field of view, e.g., as previously described with reference to Figure 4 In the sensor-equipped wafer discussed. For example, the support structure may support one or more optical sensors facing upward, such as having a field of view that is perpendicular or nearly perpendicular to the substrate. At least one of such optical sensors may be disposed at a distance radially offset from the rotation axis of the support structure, such that when the support structure is rotated relative to the substrate, the offset optical sensor follows a circular path. In such a system, the support structure may be rotated to position the optical sensors it supports below different locations on the underside of the showerhead, thereby allowing optical data to be collected from different areas of the underside of the showerhead.

[0152] In another type of sensor-equipped wafer, the optical sensor may be located on a support structure that is movable to reposition the optical sensor to a location at a greater distance from the center of the sensor-equipped wafer. Fig.19A and 9 B depicts such a sensor-equipped wafer in two different operating states. Fig.19A As shown in FIG. 1 , a sensor-equipped wafer 1900 is provided, which includes a substrate 1902 and a support structure 1964 rotatably connected to the substrate 1902. The support structure 1964 is configured to rotate relative to the substrate 1902 around an axis located offset from the center of the substrate 1902, for example, around an axis located near the edge of the substrate 1902. A rotation drive 1966 is coupled to the support structure 1964 so that when the rotation drive 1966 is rotated, the support structure 1964 also rotates - this is shown in FIG. Fig.19B , wherein the rotational drive 1966 has been rotated, thereby causing the support structure 1964 to rotate 180° relative to the substrate 1902. Thus, the support structure 1964 has been rotated from a position in which it points inwardly toward the center of the substrate 1902 to a position in which it points outwardly from the substrate 1902.

[0153] The support structure 1964 can support one or more optical sensors 1922 having a field of view 1923 as shown. When the support structure 1964 is swung outside the substrate 1902 by actuation of the rotation drive 1966, this causes the optical sensor 1922 to be positioned at a position away from where such optical sensor 1922 is located (e.g., Fig.19A This can allow the sensor-equipped wafer 1900 to obtain optical data from a component that is significantly larger than the footprint of the substrate 1902. For example, Fig.19A and 19B, the outline of the nozzle 1952 is shown, and its diameter is much larger than the diameter of the wafer 1900 equipped with the sensor. The optical sensor 1922 can be repositioned, such as Fig.19B As shown, optical data can be captured for a portion of the showerhead 1952 that is outside the outer perimeter of the substrate 1902. It should also be understood that such an implementation can also allow the optical sensor to capture optical data from a position above the interior of the substrate 1902, where there may not be any structure. For example, if the substrate 1902 is annular, i.e., has an opening in the center, such an implementation would allow the optical sensor to be repositioned above the opening so as to be able to capture optical data for the area of ​​the showerhead that is above the opening.

[0154] In some implementations, Fig.19A and Fig.19B The implementation scheme can be found in Figure 7 The sensor-equipped wafer 700 has some similarities to the sensor-equipped wafer implemented on FIG. Fig. 20 An example of such a sensor-equipped wafer is depicted. Fig. 20 , a sensor-equipped wafer 2000 is shown, which includes support structures 2064a and 2064b. The first support structure 2064a is rotatably supported by the substrate 2002 (for example, the first support structure 2064 may be coupled to the substrate 2002 via a rotary bearing), and the second support structure 2064b is rotatably supported by the support structure 2064a. Therefore, the first support structure 2064a can be rotated relative to the substrate 2002 and around its central axis in response to the rotation input provided by the first rotation driver 2066a, and the second support structure 2064b can be rotated relative to the first support structure 2064a around a rotation axis radially offset from the central axis of the substrate 2002 in response to the rotation input provided by the second rotation driver 2066b.

[0155] Such a configuration allows the second support structure 2064b to rotate between different positions, thereby causing at least some of the optical sensors 2022 located on the second support structure 2064b to move between different radial positions relative to the center of the substrate 2002 (this is in Fig. 20 In addition, the first support structure 2064a can be rotated to rotate the optical sensor 2022 located on the second support structure 2064b to a different azimuth position relative to the substrate 2002 (in FIG. Fig. 20 Such an implementation can be used, for example, to obtain a nozzle (in Fig. 202002, which is much larger than the footprint of the substrate 2002. For example, the first support structure 2064a can be rotated relative to the substrate 2002, and the second support structure 2064b can be oriented to point inwardly toward the center of rotation of the first support structure 2064a. During such rotation, the optical sensor 2022 (which can be an upward-looking imaging sensor) can be periodically obtained Optical data, such as an image, of the underside of the showerhead located above the substrate 2002 during such rotation. The second support structure 2064b can then be rotated 180° (or more generally, between 90° and 180°) relative to the first support structure 2064a to place at least some of the optical sensor 2022 and a portion of the second support structure 2064b outside of the substrate 2002. The first support structure 2064a can then be rotated relative to the substrate 2002, with the second support structure 2064b in a partially outboard position. Then, during such rotation, further optical data may be periodically obtained from the optical sensor 2022 located on the underside of the showerhead 2052 outside of the substrate 2002. The optical data collected during such rotation of the first support structure 2064a may then be composited together to form a composite data set representing the entire underside of the showerhead 2052. Such a sensor-equipped wafer may thus facilitate the collection of optical data, such as image data, from a showerhead having a diameter that is larger than the substrate diameter of such a sensor-equipped wafer (e.g., at least 25% or 50% larger).

[0156] As described above, a sensor-equipped wafer may include different sets of sensors, for example, multiple sets of optical sensors arranged to image different portions of a semiconductor processing chamber. Figures 21A to 21E Depicted are views of a sensor-equipped wafer having multiple sets of different optical sensors.

[0157] Fig.21A and 21B 2 and 3. Isometric views of the top and bottom of a sensor-equipped wafer 2100 are shown, respectively. The sensor-equipped wafer 2100 may include a substrate 2102 that may support a plurality of different sets of optical sensors 2122, such as imaging sensors. For example, a first set of optical sensors 2122a may be arranged around the periphery of the substrate 2102 and oriented such that their fields of view 2123a (see Fig. 21C ) are oriented radially outward from the central axis of the substrate 2102. Such optical sensors 2122a can be used to obtain optical data about visible properties of the inner wall of the semiconductor chamber in which the wafer 2100 equipped with the sensor will be used. A first set of illumination devices 2124a can be optionally disposed near the optical sensors 2122a, such as LEDs disposed on either side of each optical sensor 2122a and oriented to direct light radially outward. Such illumination devices 2124a can allow the surface to be imaged to be illuminated.

[0158] A second set of optical sensors 2122b may be provided distributed on the top surface of the substrate 2102. The optical sensors 2122b may be oriented such that their field of view 2123b (see Fig.21D ) can obtain optical data from a location directly above the sensor-equipped wafer 2100 (e.g., underside of a showerhead). A second set of illumination devices 2124b can also be optionally distributed on the substrate 2102 to direct light vertically upward, for example, toward the showerhead that can be imaged using the optical sensor 2122b.

[0159] A third set of optical sensors 2122c may be provided that are distributed on the top surface of the substrate 2102, but whose field of view 2123c (see Fig.21E ) is directed vertically downward, for example, through a hole formed in substrate 2102. Such an optical sensor 2122c can be used to image a location (e.g., a wafer pedestal) below a wafer equipped with the sensor, for example. It should be understood that an additional illumination source can also be provided to direct light vertically downward, if desired.

[0160] Such a sensor-equipped wafer 2100 demonstrates that it is feasible to equip a sensor-equipped wafer with a large number of different sensors arranged in different orientations and located in different areas to allow the sensor coverage to extend above, below and to the periphery of the sensor-equipped wafer, thereby allowing the sensor-equipped wafer to be used to collect data from almost anywhere within a semiconductor processing chamber or tool.

[0161] FIG. 22A to FIG. 22C Another example of an exemplary semiconductor-equipped wafer is shown in , which depicts an isometric view and two detailed views of a sensor-equipped wafer with a steerable optical sensor. Fig.22A As shown, a sensor-equipped wafer 22A may be provided having a support structure 2264 rotatably supported relative to a substrate 2202. The support structure 2264 may be rotatably driven, for example, by a first rotary drive 2266a, such that the support structure 2264 may be rotated about an axis perpendicular to the substrate 2202. The support structure 2264 may support an optical sensor 2222 mounted to a rotatable shaft, and a second rotary drive 2266b may be rotated about an axis parallel to the substrate 2202. Such an arrangement may be used to allow adjustment of the azimuth and elevation of the line of sight of the optical sensor 2222, to allow the optical sensor to be reoriented between any of a number of directions.

[0162] The sensor-equipped wafer according to the present invention may also include or alternatively include other types of sensors. For example, in some implementations, the sensor-equipped wafer may include one or more ambient atmosphere sensors, for example, which measure one or more characteristics of the ambient atmosphere surrounding the sensor-equipped wafer. In the context of the present invention, the ambient atmosphere sensor should be understood to be limited to a gas concentration sensor configured to determine at least the concentration of a non-water gaseous component of the ambient atmosphere, for example, a partial pressure sensor configured to measure the partial pressure of a non-water gaseous component in the ambient atmosphere, or a gas flow sensor configured to measure the velocity of an air flow passing through such an air flow sensor. It should be further understood that the ambient atmosphere sensor mentioned herein may also refer to a sensor configured to obtain a water concentration measurement value, for example, in addition to obtaining a concentration measurement value of at least one gas component other than water (e.g., oxygen partial pressure), the partial pressure of water is also obtained. Detecting the gas concentration of the atmospheric components (other than water) of the ambient air surrounding the semiconductor processing tool may allow, for example, the use of such a gas concentration sensor to perform leak detection (discussed in more detail below). The presence of water in a semiconductor processing chamber is generally not a good indicator for leak detection, because there may be many factors other than atmospheric air leaking into the chamber that cause the presence of water in the semiconductor processing chamber.

[0163] In some implementations, the ambient atmospheric sensor may be configured to obtain such measurements under ambient atmospheric conditions, such as those in the high vacuum to rough vacuum pressure range, such as may exist within a semiconductor processing chamber during some semiconductor processing operations (e.g., in the 40 mTorr to 550 mTorr range or lower). Examples of sensor technologies that may be used to obtain such measurements are adsorption / desorption based sensor technologies, such as substrates (e.g., gallium nitride based substrates) that selectively adsorb a particular gas species (e.g., oxygen) and have an electrical property (e.g., resistance) that varies based on the amount of gas adsorbed by the substrate. When exposed to light, such substrates may also desorb the gas species, and the gas desorption rate is proportional to the intensity of the light to which the substrate is exposed (e.g., from an illumination source configured to illuminate the substrate). When the resistance across the substrate is in a steady state, this indicates that the adsorption and desorption rates are in equilibrium. Thus, by measuring the resistance across such a substrate, and then adjusting the intensity of light emitted from the illumination source and directed to the substrate until the resistance is balanced, a light intensity level corresponding to a state in which the adsorption and desorption rates are in equilibrium may be obtained. This intensity level will be proportional to the partial pressure of the adsorbed gas and therefore to the gas concentration, and can therefore be used as a measure of the gas concentration. Such a sensor may be very compact, for example mounted within a volume of 25 mm x 10 mm x 10 mm. Of course, other suitable sensor types may be used for this purpose, and the present invention should not be considered limited to this particular example type of gas concentration sensor. It should be understood that while the exemplary ambient atmosphere sensor discussed above integrates multiple different sensor types into a single integrated chip-based package, other implementations may use discrete sensor devices, for example, each mounted separately to a substrate, to provide similar functionality.

[0164] One or more such ambient atmospheric sensors may (in some implementations) be included on a sensor-equipped wafer to provide a mobile platform that can be positioned at various locations within a semiconductor processing tool to assess atmospheric conditions at such locations. This allows assessment of atmospheric conditions within each semiconductor processing chamber of, for example, a multi-chamber semiconductor processing tool, as well as atmospheric conditions within, for example, a transfer chamber and / or load lock of the semiconductor processing tool.

[0165] In some implementations, such a sensor-equipped wafer may include a plurality of ambient atmosphere sensors disposed at different locations on the substrate surface of the sensor-equipped wafer. Fig.23An example of a sensor-equipped wafer 2300 is depicted, having a substrate 2302 supporting a plurality of ambient atmosphere sensors 2332A-E, which may be collectively referred to herein as ambient atmosphere sensors 2332. The sensor-equipped wafer 2300 is shown disposed on a pedestal 2362 within a semiconductor processing chamber 2350; a slit valve 2368 is shown that may be moved upward or downward to seal or open a wafer transport passage 2370 to the interior of the semiconductor processing chamber 2350. The ambient atmosphere sensors 2332 may be, for example, ambient atmosphere sensors configured to obtain partial pressure measurements of oxygen and water vapor in the ambient atmosphere surrounding each ambient atmosphere sensor 2332.

[0166] If multiple ambient atmospheric sensors 2332 are used, such as Fig.23 As shown, such ambient atmosphere sensors 2332 may be disposed at spaced locations on the substrate 2302. For example, Fig.23 In the embodiment, there are five ambient atmosphere sensors 2332 - one located at the center of substrate 2302, and the others located near the outer edge of substrate 2302, and spaced 90 degrees apart from each other. If multiple ambient atmosphere sensors are set at different locations, such as Fig.23 As shown, this allows for simultaneous or nearly simultaneous measurements of the partial pressure of oxygen (and, optionally, water) at different locations. Such measurements can then be used to a) obtain a more accurate assessment of whether the ambient atmospheric conditions at more than, for example, a single location relative to the substrate 2302 are within acceptable ranges, and b) determine the direction in which a potential leak may be located.

[0167] Semiconductor processing chambers are typically operated at subatmospheric pressure. Such chambers are typically machined from large pieces of metal (e.g., aluminum) to provide a sealed environment. Various openings and holes in such components are sealed with vacuum-grade seals to prevent gas from leaking from the external surroundings (e.g., atmospheric air) into the interior of the semiconductor processing chamber. Such leaks may result in increased pressure and / or may introduce contaminants (e.g., oxygen, etc.) that may negatively impact the semiconductor processing operations performed within the semiconductor processing chamber. The concentration of such contaminants and the partial pressures caused by these contaminants are generally highest at the point of introduction of such contaminants into the semiconductor processing chamber (i.e., at the location where a leak may exist), and then decrease as the distance from the leak point increases.

[0168] For clarity, it should be noted that in the context of the present invention, a "leak" is understood to refer to a location in a semiconductor processing chamber where the amount of gas leaking from the surrounding external atmosphere into the semiconductor processing chamber exceeds a predetermined threshold when the semiconductor processing chamber is at a specified pressure below atmospheric pressure. A sensor-equipped wafer (e.g., sensor-equipped wafer 2300) can, for example, be able to determine when and where the level (e.g., concentration and / or partial pressure) of a particular component (e.g., oxygen) in the ambient atmospheric air is above a particular threshold.

[0169] For a sensor-equipped wafer (such as sensor-equipped wafer 2300), an ambient atmosphere sensor 2332 may be used to obtain partial pressure measurements of oxygen. Such measurements may then be used to determine the approximate direction (relative to sensor-equipped wafer 2300) of where a leak may be located. For example, Fig.24 Depicted Fig.23 2300, but with different gas (e.g., oxygen) partial pressure levels, which are represented by different shaded areas separated by dashed lines. The depicted partial pressure levels (P1 to P5 representing pressure reductions) represent the partial pressure levels that would typically occur if, for example, a leak point existed in the seal for the slit valve 2368 at position A. Generally speaking, an ambient atmosphere sensor (which measures, for example, a partial pressure level of oxygen that is higher than the partial pressure level of such a gas measured simultaneously by other ambient atmosphere sensors on the sensor-equipped wafer 2300) will be physically closer to the leak (which is the source of the gas of interest) than these other ambient atmosphere sensors. Generally speaking, the more ambient atmosphere sensors 2332 are distributed on or along the periphery of the sensor-equipped wafer, the higher the accuracy with which the leak location can be determined using the sensor-equipped wafer 2300.

[0170] As can be seen, the ambient atmosphere sensor 2332C of the five ambient atmosphere sensors 2332 will measure the highest oxygen partial pressure P1, while the next highest oxygen partial pressure (slightly lower than P2) is measured at the ambient atmosphere sensor 2332B. Such information can be used to at least determine the sector of the sensor-equipped wafer that is closest to a potential leak, for example, it can be generally determined that the location of such a leak is within the α arc circular sector 2334 extending outward from the center of the sensor-equipped wafer 2300 and having a centerline 2336 passing through the ambient atmosphere sensor 2332 (in this example, ambient atmosphere sensor 2332C) with the highest oxygen partial pressure reading. In the case where the sensor-equipped wafer 2300 has ambient atmosphere sensors evenly spaced around the periphery of the sensor-equipped wafer 2300, the angle α can be equal to 360° divided by the number of ambient atmosphere sensors 2332 disposed along the periphery of the sensor-equipped wafer 2300. In the depicted example, α is equal to 90°, and the highest oxygen partial pressure reading at ambient atmosphere sensor 2332C therefore indicates that the leak is radially outward from the rightmost quadrant (relative to the orientation of the figure) of the sensor-equipped wafer 2300. Potential leak locations can (in some cases) be analyzed with additional granularity by considering data from other ambient atmosphere sensors 2332 on the sensor-equipped wafer 2300. For example, both ambient atmosphere sensors 2332B and 2332A measure partial pressure readings in this example, slightly below P2 for ambient atmosphere sensor 2332B and close to P3 for ambient atmosphere sensor 2332A. In contrast, ambient atmosphere sensor 2332D indicates a partial pressure reading of less than P4. Therefore, compared with the lower partial pressure measurement value of the ambient atmosphere sensor 2332D, the increased partial pressure measurement value of the ambient atmosphere sensor 2332B indicates that the leakage location "A" is located on the side of the center line 2336 closer to the ambient atmosphere sensor 2332B, thereby further narrowing the location of the leakage "A" to a position radially outward from the octant of the chip 2300 equipped with the sensor and above the center line 2336 (relative to the direction of the figure).

[0171] In general, by identifying a local peak in the partial pressure readings (e.g., a partial pressure reading reported by an ambient atmosphere sensor 2332 that is higher than the partial pressure readings reported by a circumferentially adjacent ambient atmosphere sensor 2332), a good approximation of where a potential leak or multiple potential leaks may exist can be determined. This can roughly indicate that the leak exists radially outward of the wafer equipped with the sensor and is located between radii extending outward from the center of the wafer and along an axis midway between the ambient atmosphere sensor 2332 reporting the local peak and the circumferentially adjacent ambient atmosphere sensor 2332. The location of the leak can be further refined, for example, to one side or the other side of the ambient atmosphere sensor 2332 reporting the local peak partial pressure based on which of the ambient atmosphere sensors 2332 circumferentially adjacent to the ambient atmosphere sensor 2332 reporting the local peak partial pressure reports the higher partial pressure.

[0172] It should be understood that while the above examples have featured an ambient atmosphere sensor that measures the partial pressure of oxygen, similar techniques may be implemented using partial pressure sensors that measure the partial pressures of other gases that may be present in ambient atmospheric air, such as nitrogen (N2), argon (Ar), carbon dioxide (CO2), and neon (Ne). It should also be understood that other types of gas concentration sensors (in addition to partial pressure sensors) may be used in place of or in addition to the partial pressure sensors described above. It should also be understood that during such measurements, the gas whose partial pressure is being sought may be prevented from otherwise flowing into the semiconductor processing chamber, for example, if the semiconductor processing tool is configured to supply oxygen to the semiconductor processing chamber during some stages of normal semiconductor processing operations, such intentional oxygen delivery may be prevented during leak testing, such that the only potential source of oxygen (or other gas detectable by the ambient atmosphere sensor) is a leak at one or more locations within the semiconductor processing chamber.

[0173] Such a semiconductor processing chamber may also include an exhaust system that can be used to exhaust process gases introduced during semiconductor processing operations and maintain a desired vacuum level within the semiconductor processing chamber. During leak testing, it may also be necessary to temporarily disable such an exhaust system to avoid affecting the partial pressure level of contaminants within the semiconductor processing chamber. Thus, for example, the above-mentioned gas concentration measurements can be performed in a semiconductor processing chamber using a wafer 2300 (or the like) equipped with a sensor, and the internal atmosphere of the semiconductor processing chamber is not disturbed by gas flows flowing in (except, of course, for any potential leaks) or out, movement of components within the semiconductor processing chamber (e.g., changes in the height of the pedestal and / or showerhead), opening and / or closing operations of valves and / or doors, or startup of systems (e.g., turbo pumps or cryopumps). By performing such measurements in a "static" internal ambient atmosphere, potential sources of partial pressure changes other than potential leak points can be minimized or eliminated, thereby increasing the likelihood of accurately detecting such leaks and identifying where such leaks may be located.

[0174] It will be further understood that some implementations of the sensor-equipped wafer may have a gas concentration sensor that may be configured to obtain readings of gases other than those commonly found in atmospheric air, such as gases that may be used in semiconductor processing operations, gases that may be byproducts of such processing operations, and / or gases that may be introduced into the processing chamber from other locations within the tool (e.g., from other processing chambers within the tool) (e.g., which may be accompanied by a wafer being transferred to the chamber from another chamber within the tool). For example, in some implementations, the sensor-equipped wafer may be configured to have a gas concentration sensor that detects hydrogen species (H x ), ozone (O3), nitrogen oxides (NO x One or more gas concentration sensors for ), chlorofluorocarbons (CFCs), methane (CH4), and / or volatile organic compounds (VOCs). Such chemicals may, for example, outgas from materials deposited on wafers within the processing chamber. Such material liquids may be deposited on surfaces of the processing chamber and thus remain in the processing chamber even after the wafer or wafers being processed are removed. Materials remaining in the processing chamber after the wafers are removed may, for example, outgas or react with other gases within the processing chamber to produce gaseous species that, if their concentration exceeds a certain threshold, may be deemed sufficiently detrimental to the processing operations to be performed in such a processing chamber to warrant corrective action, such as cleaning the chamber or removing the chamber from the tool and replacing it with a new chamber.

[0175] In some implementations, the sensor-equipped wafer may include a particle sensor, such as an ionization or photoelectric particle sensor (e.g., similar to the sensors used in smoke detectors to detect smoke particles, but perhaps more sensitive). In an ionization detector, a small sample of radioactive material is provided to ionize or charge gas molecules of the atmosphere being sensed between two metal plates (e.g., electrodes) in a sample chamber that is fluidly connected to the monitored atmosphere. When solid particles (e.g., particles) flow through the chamber, they attract the ionized material and carry it away, thereby reducing the current flowing between the two electrodes. The amount of current reduction enables a measurement of the amount of particles that may be present. In a photoelectric particle detector, a light source may be configured to direct a light beam so that the light beam passes through a photodetector associated with the light source without irradiating it, e.g., the light beam passes in front of and parallel to the photosensitive surface of the photodetector but is not incident thereon. However, when particles are present in the atmosphere in front of the photodetector, some of the light that would normally pass through the photodetector instead strikes the particles and is scattered, resulting in some of the scattered light striking the photodetector. Such an amount of light striking the photodetector enables a measurement of the concentration of particles in the atmosphere.

[0176] A sensor-equipped wafer having one or more particle sensors can be used to detect the presence of particle contamination within a semiconductor processing chamber. Such particles may be caused, for example, by mechanical wear between moving parts within the processing chamber (e.g., lift pins and / or susceptors moving up and down, wafer handling robots moving within the chamber, showerheads moving within the chamber, etc.), or may be a byproduct of semiconductor processing operations, for example, deposited material that may have been deposited on surfaces of the semiconductor processing chamber and may have been detached from such surfaces, for example, by flaking.

[0177] It should be understood that techniques similar to those discussed above for sensor-equipped wafers with atmospheric gas concentration sensors (e.g., for leak detection) may also be used with gas concentration sensors configured to detect gas species not normally present in atmospheric air, but for slightly different purposes. For leak detection, the gas being detected is generated within the processing chamber via a leak path from the ambient atmosphere surrounding the tool. For sensor-equipped wafers with gas concentration sensors configured to detect gases other than those in atmospheric air, the gas being detected may be generated within the processing chamber by exhaust or other mechanisms. Thus, techniques for detecting the location of potential leak points using a gas concentration sensor configured to detect oxygen may similarly be used with a gas concentration sensor configured to detect, for example, CFCs exhausted from a deposited film within a processing chamber. Rather than being used to indicate a potential leak detection point, such techniques may be used to indicate one or more regions in the chamber where the maximum concentration of such deposited film exists. Similarly, such techniques may also be implemented with a particle sensor to achieve a similar effect, such as to detect one or more regions in the processing chamber where the maximum particle concentration is generated.

[0178] Some implementations of a sensor-equipped wafer may have (possibly in addition to other sensors discussed herein) one or more gas concentration sensors and / or one or more particle sensors. In some implementations, such a sensor-equipped wafer may include multiple gas concentration sensors configured to detect the same gas species (e.g., to facilitate determining the location of a leak or the location of an area in a chamber where the greatest outgassing occurs). In some other or additional such implementations, gas concentration sensors or groups of gas concentration sensors for detecting different gas species may be located on a common sensor-equipped wafer. For example, a sensor-equipped wafer may have one group of gas concentration sensors for detecting oxygen (for leak detection) and another group of gas concentration sensors for detecting CFCs (for detecting gas exhaust locations of deposition byproducts on chamber surfaces).

[0179] In a semiconductor processing tool in which such a sensor-equipped wafer may be used, a controller of the semiconductor processing tool may be configured to move such a sensor-equipped wafer between different locations, for example, between a storage or loading location of the semiconductor processing tool and a semiconductor processing chamber. The semiconductor processing tool controller may be further configured to send one or more commands to the sensor-equipped wafer, for example via a wireless communication connection, so that the controller of the sensor-equipped wafer obtains one or more sensor readings via its ambient atmosphere sensor. For example, a concentration or partial pressure measurement of a particular component (e.g., oxygen) of a gas within a semiconductor processing chamber and around the sensor-equipped wafer may be caused to be obtained. The semiconductor processing tool controller may also cause various other operations to be performed before such measurements may be caused to be obtained.

[0180] Fig.25 An exemplary semiconductor processing tool (or portion thereof) is depicted that may be configured to utilize a method similar to that described above with respect to Fig.23 and Fig.24 The wafer equipped with the sensor in question can be Fig.25 As seen in FIG. 2 , a semiconductor processing tool 2548 is shown having a vacuum transfer module 2580 and connected thereto six semiconductor processing chambers 2552. A wafer handling robot 2554 may be located within the vacuum transfer module 2580 and may be configured to be able to move wafers between the various semiconductor processing chambers 2552 (not shown are load locks that may be used to transfer wafers from, for example, an EFEM into and out of the vacuum transfer module 2580, for example).

[0181] Each semiconductor processing chamber 2552 may have a pedestal 2562 and a showerhead 2553 located therein. The pedestal may be configured to allow the flow of gas provided by one or more gas sources 2576 when one or more valves (represented by a double end-to-end triangle symbol) are controlled by a controller 2574 to be opened (e.g., during semiconductor processing operations). Each semiconductor processing chamber 2552 may also include a door 2568 that may be controlled by the controller 2574 to switch between an open and a closed state, thereby allowing the semiconductor processing chamber 2552 to be sealed and opened to allow wafers to pass into or out of the semiconductor processing chamber 2552, for example, during wafer processing operations. The semiconductor processing tool 2548 may also have or be connected to a vacuum pump 2578 that may be fluidly connected to each semiconductor processing chamber 2552 to enable exhaust of processing gases from the semiconductor processing chamber 2552. The exhaust flow from each semiconductor processing chamber 2552 may be regulated by a corresponding valve controlled by the controller 2574, for example, to allow the exhaust of each semiconductor processing chamber 2552 to be increased or decreased as needed, or even stopped completely.

[0182] As can be seen, the controller 2574 may be caused, for example, by computer executable instructions stored in a memory device, to control the wafer handling robot 2554 to place the sensor-equipped wafer 2500 into one of the semiconductor processing chambers 2552 (in this case, shown as the upper left semiconductor processing chamber 2552). The controller 2574 may then cause the wafer handling robot 2554 to withdraw from the semiconductor processing chamber 2552, leaving the sensor-equipped wafer 2500 in position on the pedestal 2562, as shown by the dashed outline of the center left semiconductor processing chamber 2552. Once the wafer handling robot 2554 has been withdrawn from the semiconductor processing chamber 2552, the controller 2574 may stop the flow of gas from the one or more gas sources 2576 to the semiconductor processing chamber 2552, for example, by controlling one or more valves to transition to a closed state, and may cause the chamber door 2568 to transition to a sealed state (shown in the center left semiconductor processing chamber 2552 by the chamber door 2568 being colored black). The controller 2574 may then send a command or commands to the sensor-equipped wafer 2500 to cause the sensor-equipped wafer 2500 to obtain one or more sensor readings from one or more ambient atmosphere sensors located thereon (represented by the five small squares in the sensor-equipped wafer 2500). Data from the sensor readings may then be stored, for example, in a memory on the sensor-equipped wafer and / or transmitted to the controller 2574 for further processing.

[0183] Controller 2574 and / or a controller of a wafer equipped with a sensor can, for example, determine a) whether there is a potential leak (based on a peak concentration or partial pressure of a particular component of the ambient atmospheric air (e.g., oxygen) within the semiconductor processing chamber being above a predetermined threshold level) and in some cases b) the possible location of one or more such leaks, as discussed above.

[0184] In some alternative or additional implementations, the ambient atmospheric sensor used may include an ambient atmospheric sensor configured to obtain measurements under non-vacuum ambient atmospheric conditions, for example, at a pressure at or near one atmosphere, such as may exist in an equipment front end module (EFEM), a front opening wafer transport box (FOUP), or other equipment that holds semiconductor wafers within a semiconductor processing tool or during transfer between semiconductor processing tools or other equipment.

[0185] In such an implementation, the ambient atmospheric sensor used may include one or more different types of sensors, including but not limited to relative humidity sensors, oxygen level sensors, temperature sensors, and airflow sensors (e.g., anemometers). A sensor-equipped wafer equipped with one or more such sensors may, for example, be used to evaluate and / or characterize different aspects of equipment operating under atmospheric conditions. For example, while the atmosphere within an EFEM is generally maintained at or near atmospheric pressure levels, in some cases, the atmosphere within such an EFEM may be pre-conditioned to have a specified humidity level and / or temperature. In some cases, an EFEM may have an atmosphere that is significantly different in composition from ambient atmospheric air, for example, an atmosphere from which most or all of the oxygen has been removed and / or from which only nitrogen or nitrogen concentrations much greater than those in the atmosphere may be supplied to the EFEM.

[0186] Ambient atmospheric sensors that measure humidity, thermometers, and / or gas concentrations can thus be used to assess what the actual humidity level, temperature level, and / or gas concentration within such an EFEM may be. Such measurements are then compared to target values ​​to determine whether the EFEM has the desired internal environment. It should be understood that such measurements can also be similarly obtained with such sensor-equipped wafers in other environments, such as within a wafer storage buffer, within a FOUP, within a wafer cassette, etc.

[0187] As described above, some sensor-equipped wafers may be equipped with one or more airflow sensors to allow measurements of the velocity of air (or other gas or gas mixture) over the sensor-equipped wafers to be obtained. Such measurements may, for example, allow the effectiveness of various airflow systems within an EFEM, FOUP, buffer, or other system to be evaluated ("airflow" is understood to include systems that can operate using gases other than air (e.g., nitrogen)). For example, in some buffers and / or FOUPs, an inert gas (e.g., nitrogen) may be introduced into such a structure and then exhausted therefrom in a manner that will result in a specific minimum amount of airflow above each wafer (which may be placed therein). For example, a buffer may have a set of 25 shelves arranged in a vertical stack with a spacing of 10 mm between each pair of shelves. Each shelf may be used to temporarily support a wafer while the wafer occupies the buffer. The buffer may have a gas inlet that directs an inert gas (e.g., nitrogen) into the buffer so that at least some of the inert gas flows over the top of each wafer loaded into the buffer (when the buffer is full). In such a buffer, a specified minimum level of inert gas flow may be required above each wafer, regardless of the position of the wafer. Sensor-equipped wafers (such as those discussed above) equipped with airflow sensors can be placed at different wafer positions within such a buffer, and the airflow sensors are used to achieve direct measurement of the amount of airflow occurring above the wafer (which can be placed at each of these positions).

[0188] Such an airflow sensor may, for example, comprise an anemometer, such as a hot wire anemometer. Such a sensor may have a small size to be suitable for use on a wafer equipped with the sensor. For example, an air velocity sensor based on a low-profile surface-mount microelectromechanical systems (MEMS) having a thickness of only a few millimeters (e.g., 4 millimeters or less) may be used. Such a sensor may operate as a hot wire anemometer, where air flows through a wire carrying an electric current. When the air cools the wire, this changes the resistance of the wire in a manner corresponding to the velocity of the airflow through the wire. Such a sensor is suitable for use on a wafer equipped with the sensor that may, for example, need to maintain an overall maximum thickness of 5 mm or less to be transported within a semiconductor processing tool without violating the clearance requirements of the semiconductor wafer.

[0189] Fig.26 A schematic diagram depicting a portion of a semiconductor processing tool. Fig.26, an EFEM 2684 is shown. The EFEM 2684 may have a plurality of load ports 2686 connected thereto, each of which may receive a FOUP 2688, which may contain or receive wafers to be processed or have been processed in a semiconductor processing tool. The EFEM 2684 may have a wafer handling robot 2654 located therein, which is configured to move wafers between the FOUP 2688, the load lock 2692, and / or the buffer 2682. The controller 2674 may control the wafer handling robot 2654 and various other systems of the EFEM 2684, such as a FOUP door, a load lock door, etc.

[0190] Buffer 2682 may, for example, have a plurality of wafer storage locations arranged in a stacked configuration (e.g., Fig.26 ). In some examples, buffer 2682 may have a pressurized plenum for introducing a gas (e.g., nitrogen or other gas that does not react with the wafers loaded therein) into the buffer so that the gas then flows through the wafers stored therein, e.g., along the path indicated by the arrows within buffer 2682.

[0191] A controller 2674 in such a semiconductor processing tool may cause the wafer handling robot 2654 to move the sensor-equipped wafer 2600 between a plurality of locations 2690 and, when the sensor-equipped wafer 2600 is at each location 2690, send one or more commands to the sensor-equipped wafer 2600 to cause the sensor-equipped wafer 2600 to obtain sensor readings, such as airflow readings, from one or more ambient atmospheric sensors located thereon. Such readings may be stored on the sensor-equipped wafer (e.g., in a memory located on the sensor-equipped wafer) or transmitted to the controller 2674.

[0192] In some implementations, the sensor-equipped wafer may include one or more acoustic sensors (e.g., audio sensors or microphones) that can be used to collect audio data from the surrounding environment or from the sensor-equipped wafer itself. In some embodiments, the one or more acoustic sensors may have a capacitive microphone, a peak detector, and an amplifier. For example, if the bearings of a wafer handling robot that is transporting a sensor-equipped wafer having one or more microphones begin to degrade, this may cause the end effector of the wafer handling robot to have small vibrations, which are then transmitted to the sensor-equipped wafer. Such vibrations may produce audible noise artifacts (artifacts), that is, acoustic wave signals that may have a characteristic spectrum and / or signal intensity, which are transmitted through the structure of the sensor-equipped wafer itself, for example, the sensor-equipped wafer may vibrate so that a portion of it repeatedly breaks away from the support feature of the end effector and then falls back onto the support feature, resulting in a series of rapid contact events between the sensor-equipped wafer and the support feature, each contact event resulting in an acoustic pulse, which is transmitted through the structure of the sensor-equipped wafer and then detected by the microphone mounted thereon. Such a sound signal may, for example, have a frequency in the range of 20 Hz to 20,000 Hz.

[0193] Such microphone-equipped wafers can also be used to detect acoustic events that result in acoustic waves being transmitted through the atmosphere (as opposed to propagating through solid materials) to reach the microphone. For example, equipment that is beginning to malfunction or is experiencing excessive wear and tear may produce sounds that such microphone-equipped wafers can detect, allowing such problems to be detected within a processing chamber or vacuum transfer chamber. In some sensor-equipped wafers, multiple microphones may be used and placed in different locations, for example, similar to the description of Fig.23 The arrangement of the gas concentration sensors discussed above to allow the location of the source of a detected acoustic event relative to a wafer equipped with the sensors to be determined, similar to how gas concentration sensors are used to detect leaks. This may allow, for example, a sensor-equipped wafer with a microphone to be used not only to detect acoustic events that may indicate a potential component failure, but also to determine the approximate location of the origin of the acoustic event, which may help identify which component is the source of the acoustic event (and therefore may require replacement or repair).

[0194] Generally speaking, sound data from a microphone sensor will provide time domain data indicating the strength of a sound signal at any given moment. However, such sound data may represent multiple different sound signal sources that are combined together and received simultaneously by the microphone sensor as a single mixed sound signal. Such sound data may be subjected to various types of post-processing, for example, to provide data that is more suitable for various analysis techniques.

[0195] For example, analog-to-digital conversion can be used to convert an analog signal from a microphone sensor into a digital representation. The digitized data from the continuous time intervals can then be processed using a fast Fourier transform to obtain frequency domain data, from which the power spectral density over the time interval can be determined. The power spectral density provides information related to the signal strength at different frequency bins. As discussed below, such information can be used to characterize the possible sources of such sound signals and determine the possible location of the sound signals.

[0196] Fig. 27 An example of a sensor-equipped wafer 2700 is depicted, including a plurality of microphone sensors 2738, such as microphone sensors 2738A-2738E. Fig. 27 27. The sensor-equipped wafer 2700 is shown on a susceptor 2762 within a chamber 2750. The chamber 2750 may include a wafer transfer passage 2770 through which the sensor-equipped wafer 2700 may be inserted into or removed from the chamber 2750.

[0197] The microphone sensors 2738A-2738E are omnidirectional microphone sensors in this example, which are arranged in a dispersed manner on the substrate 2702. As shown, the microphone sensors 2738A-2738E are arranged in a cross pattern, with one microphone sensor 2738A located in the center of the substrate 2702, and the remaining four microphone sensors 2738B-E are arranged in a circular, evenly spaced array at the edge of the substrate 2702. It should be understood that more or fewer microphone sensors 2738 can be used, for example, as few as three microphone sensors 2738 can be used to determine the direction from which a particular sound is emitted, which is achieved by triangulation based on the time points at which each individual microphone sensor 2738 detects the same sound signal and / or by trilateration based on the signal strength measured by each microphone sensor in response to the same sound event. In either case, the signal detected by each microphone sensor can be used as a simulation of the distance between the source of the sound event being detected and the microphone sensor.

[0198] In triangulation, the intensity or signal strength of the sound signal detected by each microphone sensor can be used as an indication of the distance between each microphone sensor and the source of the sound event of interest. In triangulation, the difference in time points between the microphone sensors receiving the same sound signal can be used as an indication of the relative distance from each microphone sensor to the source of the sound event. In triangulation, the distance simulation can take the form of a scalable component (represented by the difference in time points between the sound event signals received between the microphone sensors) plus a constant component (which is the same for all signals - this represents the shortest distance between any microphone sensor and the source of the sound event, that is, the distance between the source of the sound event and the microphone sensor closest to it). It should be understood that in the case of triangulation or triangulation, the signal being evaluated (whether in terms of signal strength or reception time point) may actually be a sub-part of the sound signal, such as a sub-signal of a specific frequency range. For example, after converting the sound signal into the frequency domain by fast Fourier transform, the analysis can indicate that the frequency bin with the highest signal strength contribution to the overall signal is the 190Hz to 200Hz frequency bin. For purposes of triangulation and / or trilateration techniques, the reception times and / or signal strengths obtained and evaluated in each such technique may be determined based on the reception times or signal strengths of sound signal components in the 190 Hz to 200 Hz frequency interval.

[0199] Each distance simulation can be thought of as defining the radius of a circle centered at the corresponding microphone sensor. In an ideal situation (where the distance simulation is scaled to match the actual distance between the corresponding microphone sensor and the source of the sound event), the circle will pass entirely through the point corresponding to the source of the sound event (or, to account for potential measurement errors, through a circular area centered at this point - the size of the circular area can be selected to be commensurate with the desired level of position determination accuracy). Since the positions of the microphone sensors on the substrate relative to each other are known, the position of the sound event relative to the substrate can be determined by adjusting the scaling of the distance simulation until a solution is found for some or all of the points (or circular areas) where the above circles intersect; the points of intersection will represent the position of the source relative to the substrate. If the position and orientation of the substrate relative to the processing chamber is known, this enables the position of the sound event relative to the chamber to be determined.

[0200] For trilateration, scaling of the distance simulation may involve scaling only the distance simulation (for trilateration) or scaling the scalable component of the distance simulation and also varying the constant component of the distance simulation (for trilateration).

[0201] The ideas discussed above are Fig. 272742A, 2742B, and 2742C (centered on the three microphone sensors 2738A, 2738B, and 2738C). Similar circles are not shown for microphone sensors 2748D and 2738E, but such circles may be added if desired. Fig. 27 Also shown are sound signals 2740A, 2740B, and 2740C detected by microphone sensors 2738A, 2738B, and 2738C at the same time interval (where time is along the x-axis and signal strength is along the y-axis) in response to a sound event occurring at sound event location 2744. It can be seen that sound signals 2740A, 2740B, and 2740C have different maximum signal strengths, as shown by the horizontal dashed lines that coincide with the peaks of sound signals 2740A, 2740B, and 2740C.

[0202] Circles 2742A, 2742B, and 2742C are shown with radii proportional to the corresponding signal strengths of acoustic signals 2740A, 2740B, and 2740C. Circles 2742A, 2742B, and 2742C have been scaled in this example to all intersect at a common point, namely, location 2744. Thus, the radius of circles 2742A, 2742B, and 2742C represents the actual distance between each microphone sensor 2738A, 2738B, and 2738C and location 2744. By solving for the location where all three circles 2742A, 2742B, and 2742C intersect, the location of location 2744 relative to substrate 2702 can be determined, thereby allowing the location of location 2744 relative to chamber 2750 to be subsequently determined.

[0203] Additional microphone sensors 2738 beyond the three such microphone sensors 2738 may provide additional sound signal data that may be used to additionally refine any signal direction determinations performed using data collected by such microphone sensors 2738 .

[0204] exist Fig.28 , another example of a sensor-equipped wafer 2800 is shown. The sensor-equipped wafer 2800 may include a substrate 2802 supporting a plurality of microphone sensors 2838, which in this example are directional microphone sensors. Such microphone sensors 2838 may have directional bias in their sensitivity, for example, the sensitivity to sound signals may vary in azimuth. Fig.28, a pickup area 2846 is shown to represent that the relative sensitivity of each microphone sensor 2838 varies with azimuth direction relative to the microphone sensor 2838. The farther any portion of the dashed line representing the pickup area 2846 is from the corresponding microphone sensor 2838, the more sensitive the microphone sensor 2838 is to sound signals produced along a line extending from the microphone sensor 2838 to that portion of the dashed line.

[0205] like Fig.28 As shown, the microphone sensors 2838 are arranged in an equally spaced circular array around the outer perimeter of the substrate 2802. Such an arrangement can allow the azimuthal direction along which a sound event occurred to be quickly determined, for example, by identifying two or three such microphone sensors 2838 that detected the highest intensity signal generated by the sound event. For example, if one microphone sensor detected the highest intensity signal generated by a sound event, and two microphone sensors to the side of that sensor detected sound signals of equal signal strength, it can be assumed that the sound event occurred at a location along a radius extending outward from the center of the substrate 2802 and passing through the microphone sensor 2838 that detected the highest intensity signal. If the two side microphone sensors 2838 are unequal in size, the microphone sensor 2838 of the two side microphone sensors 2838 that detected the second highest signal strength sound signal can be used together with the highest intensity sound signal to determine a ratio that can be applied to the angular spacing between the microphone sensors 2838 to determine the direction from which the sound signal appears to originate.

[0206] For example, in the depicted example, the angular spacing between the microphone sensors 2838 is 45°. If the microphone sensor 2838 at the 12 o'clock position detects the highest intensity signal (S1) of a sound event, and the microphone sensor 2838 to its right detects the second highest intensity signal (S2) of the sound event, it can be determined that the azimuthal direction (relative to the center of the substrate 2802) at which the location of the sound event is located is between the two microphone sensors 2838 that recorded the highest signal intensity from the sound event and are offset by an angle θ from a first radius (which extends from the center of the substrate 2802 to the center of the microphone sensor that detected the sound signal with the highest signal intensity). The angle θ can be determined by multiplying the angle defined between the first radius and the second radius (which extends from the center of the substrate 2802 to the center of the microphone sensor that detected the sound signal with the second highest signal intensity) by S1 / (S1+S2).

[0207] Such a determination can be used to identify the azimuth angle at which the acoustic event originates relative to the substrate 2802. Further determinations can be made of the relative orientation of the substrate 2802 relative to the chamber to determine the direction at which the acoustic event originates relative to the chamber.

[0208] Fig.29Another exemplary sensor-equipped wafer is depicted in the context of a process chamber. Fig.29 2950. As shown, the sensor-equipped wafer 2900 is supported on a base 2952 of a chamber 2950. The sensor-equipped wafer 2900 includes a substrate 2802 that rotatably supports a support structure 2964. The support structure 2964 can be rotated, for example, by a rotation drive 2966. The support structure 2964 can support a microphone sensor 2938; the microphone sensor 2938 can be a directional microphone, similar to the directional microphone sensor 2838 discussed previously. The dashed line 2946 indicates the pickup area of ​​the microphone sensor 2938. As can be seen, when the support structure 2964 is rotated, for example, as shown in FIG. Fig.29 The clockwise manner shown allows the microphone sensor 2938 to be rotated about the center of rotation of the support structure 2964, thereby reorienting the pickup area so that the axis of maximum sensitivity of the microphone sensor can be changed to any desired angle. This allows the microphone sensor 2938 to be used to scan the audio signal in azimuth around the perimeter of the substrate 2902.

[0209] For example, the support structure 2964 may be rotated through a plurality of different angular positions, and data may be collected from the microphone sensor 2938 at each such angular position. If such a rotational scan is performed when a sound event occurs, the angular position at which the highest sound signal strength for the sound event is detected will generally indicate the direction in which the sound event occurred. For example, when the support structure 2964 is oriented so that the sound signal detected by the microphone sensor 2938 is at a maximum, a radius extending from the center of rotation of the support structure 2964 through the microphone sensor 2938 may be aligned with the origin of the sound event.

[0210] In the above discussion of techniques for directionally locating a source of an acoustic signal using a microphone sensor, it may be desirable to obtain such acoustic measurements while the chamber in which the measurements are made is maintained sufficiently to transmit the acoustic waves without experiencing undesirable acoustic signal attenuation. Thus, for example, a processing chamber (or other chamber) in which such measurements are made may be controlled to flow a gas (e.g., a chemically inert or non-reactive gas such as argon or nitrogen) into the chamber to provide a sound propagation medium.

[0211] In some implementations, a sensor-equipped chip having one or more microphone sensors may be used to determine the origin of a sound event using, for example, acoustic fingerprinting techniques. For example, as previously described, the sound data collected by the microphone sensor may be analyzed to obtain a power spectral density of the sound signal. Such power spectral density data may be provided to a machine learning algorithm, which classifies the obtained power spectral density into one of several potential sound event types or sources based on the characteristics of the power spectral density data. For example, a particular sound signal, after being converted into the frequency domain and analyzed to obtain a power spectral density, may exhibit characteristics consistent with a sound fingerprint, wherein the three highest signal intensities appear in the frequency bands of 100 Hz, 120 Hz, and 200 Hz (each ±5 Hz), and wherein the signal intensities of the 120 Hz and 200 Hz frequency components are 50% ± 20% of the signal intensities of the 100 Hz frequency component.

[0212] Such a machine learning algorithm may, for example, be trained using sound signal data obtained from such a sensor-equipped wafer under conditions that produce sound events (known to be caused by an error or operating condition). For example, such a machine learning algorithm (e.g., a neural network) may be trained using a dataset of sound signal data obtained from a sensor-equipped wafer having a microphone sensor while the sensor-equipped wafer is transported by a wafer handling robot that is known to produce sound events caused by, for example, a rotating bearing that is nearing the end of its useful life. Different datasets of sound signal data caused by different potential sound signal sources (error conditions) may be provided to the machine learning algorithm to train the algorithm to recognize a variety of different sound signal types, each sound signal type serving as a fingerprint for a specific error condition that produces such sound signal type. When a specific potential source / error condition associated with a specific sound print is identified, a notification may be generated to notify an operator of the potential error condition.

[0213] For example, the voiceprint recognition techniques described above may allow the location of a particular sound event to be determined without necessarily relying on multiple microphone sensors or movable microphone sensors, for example, if the voiceprint is associated with a particular component in a semiconductor processing tool. This enables a sensor-equipped wafer to collect sound signal data, for example, under vacuum conditions, and still identify the location where the sound event may have occurred. For example, the sound signal may be provided to the sensor-equipped wafer 2900 via acoustic coupling from a solid structure (e.g., via the structure of the wafer handling robot itself). By analyzing the received sound signal and matching the intensity of the frequency components therein with the voiceprint, the source of the sound signal (the component of the semiconductor processing tool that generated the signal) can potentially be identified, thereby identifying where the sound signal originated.

[0214] Because the sensor-equipped wafers discussed herein are self-powered (e.g., with a battery or other power source) and are configured to communicate with one or more other devices (e.g., via a wireless connection), such sensor-equipped wafers can provide an extremely flexible architecture for collecting measurements that can be used to identify, evaluate, characterize, and / or quantify multiple aspects of semiconductor tool performance. For example, in some implementations, such sensor-equipped wafers can be configured to receive commands indicating that one or more measurements are to be taken by one or more sensors of the sensor-equipped wafer. A controller separate from the sensor-equipped wafer (e.g., a tool controller that can control various systems of a semiconductor processing tool) can be configured to establish a communication link with the sensor-equipped wafer and then periodically send instructions to the sensor-equipped wafer to obtain the desired set of measurements for the sensor-equipped wafer. For example, the controller can be provided with computer-executable instructions that cause the controller to cause a wafer handling robot of a semiconductor processing tool to retrieve the sensor-equipped wafer from, for example, a dedicated storage slot in an EFEM or from a FOUP storing the sensor-equipped wafer and move it to one or more locations within the EFEM (and / or a buffer and / or FOUP). Such instructions may also cause the controller to send instructions to the sensor-equipped wafer between locations, causing the sensor-equipped wafer to obtain one or more measurements at each such location using one or more sensors in the sensor-equipped wafer.

[0215] Measurement data collected by such a sensor-equipped wafer may (in some instances) be stored in one or more memory devices on the sensor-equipped wafer and subsequently retrieved. In other or additional instances, such measurement data may be transmitted in real time or near real time to an external device, such as a controller of a semiconductor processing tool using the sensor-equipped wafer, using a wireless interface of the sensor-equipped wafer, if present. In the case where the sensor-equipped wafer additionally includes sensors such as relative humidity sensors, temperature sensors, or the like, the sensor readings obtained may also include measurement data from such additional sensors.

[0216] In some implementations, the sensor-equipped wafer may include a gas flow sensor and a gas concentration and / or partial pressure sensor for atmospheric or near-atmospheric conditions. For example, some EFEMs may be configured to have an internal atmosphere within the EFEM that has a gas composition that is different from the gas composition present in the surrounding atmosphere. For example, such an EFEM may be configured to maintain a pure nitrogen atmosphere (or at least an atmosphere without the presence of oxygen). In actual practice, it is not possible to maintain such an environment because the EFEM is generally not sealed (unlike a semiconductor processing chamber, which is sealed to be able to be maintained at a pressure below atmospheric pressure, such as a vacuum). Therefore, there will generally be at least some ambient atmospheric air (containing oxygen) that leaks into such an EFEM. Accordingly, it may be desirable to quantify the amount of oxygen that leaks into such an EFEM—if it is within acceptable limits, the EFEM may be considered to have an internal atmosphere that is sufficiently oxygen-free so that wafers passing therethrough are not exposed to an unacceptable risk of contamination. However, if the oxygen level within the EFEM exceeds such a threshold, the semiconductor processing tool controller may generate an error condition to alert the operator that oxygen may be leaking into the EFEM at an unacceptable rate.

[0217] In such a system, one or more small surface-mount gas sensors (e.g., oxygen sensors) may be included in the sensor-equipped wafer in addition to (or in place of) the airflow sensor. For example, a low-profile side-mounted gas sensor (e.g., oxygen sensor) may be used, such as is commonly used in medical or safety equipment. Such a sensor may be an electrochemical device that consumes a fuel (e.g., oxygen) to produce an electrical output through a chemical reaction, and has a package height of less than 7 mm thickness (in some cases), making it suitable for use with the sensor-equipped wafer. Such a sensor package may, for example, be modified to be slightly thinner to achieve a total maximum thickness of the sensor-equipped wafer of, for example, less than 5 mm, or may be used as is when the total thickness of the sensor-equipped wafer is greater than, for example, 5 mm. For example, for a sensor-equipped wafer designed for use within an EFEM, the height restriction may be slightly relaxed than for a sensor-equipped wafer configured for use within a semiconductor processing chamber. Thus, for a sensor-equipped wafer that may not need to be transported to the interior of a semiconductor processing chamber, a sensor-equipped wafer may be allowed to have a slightly larger maximum thickness, such as 6 mm to 8 mm.

[0218] The controller 2674 (or controller 2574) may be further configured to analyze data collected from the ambient atmosphere (or other) sensors on the sensor-equipped wafer and determine whether the ambient atmosphere conditions within some portion of the semiconductor processing tool (measured using the sensor-equipped wafer) meet the required minimum threshold or thresholds. If not, the controller may cause an error condition to be reported and may, for example, prevent operation of the semiconductor processing tool or at least the relevant portion thereof until a subsequent set of sensor wafer measurements indicates that the problem has been resolved or until an operator provides, for example, a replacement command.

[0219] It should be understood that while the exemplary sensor-equipped wafers discussed above tend to each focus on sensor-equipped wafers that include only a single type of sensor, e.g., one or more upward-facing optical sensors, one or more radially-outward-facing optical sensors, one or more ambient atmospheric sensors, etc., sensor-equipped wafers may also be configured to include multiple different types of sensors, e.g., ambient atmospheric sensors and upward-facing and / or radially-outward-facing optical sensors. In addition, some sensor-equipped wafers may further include one or more of the following: one or more accelerometers, one or more proximity sensors, one or more relative humidity sensors, one or more temperature sensors, one or more sound sensors, etc.

[0220] It should also be understood that the sensor-equipped chips discussed herein may have sensors mounted to the top surface of a substrate (or other structure supported by a substrate), sensors mounted to the underside of a substrate, sensors mounted within the substrate, sensors mounted near the periphery of the substrate, and / or sensors mounted to the edge of a substrate.

[0221] As described above, the controller discussed herein can be part of a system that can include semiconductor processing equipment, including one or more processing tools, one or more chambers, one or more platforms for processing, and / or specific processing components (wafer pedestals, gas flow systems, etc.). These systems can be integrated with electronic devices for controlling their operation before, during, and after the processing of semiconductor wafers or substrates. The electronic device can be referred to as a "controller" that can control various components or subcomponents of one or more systems. Depending on the processing requirements and / or system type, the controller can be programmed to control any of the processes disclosed herein, as well as various parameters that affect semiconductor processing, such as the delivery of process gases, temperature settings (e.g., heating and / or cooling), pressure settings, vacuum settings, power settings, radio frequency (RF) generator settings, RF matching circuit settings, frequency settings, flow rate settings, fluid delivery settings, position and operation settings, wafer transfer in and out tools and other transfer tools and / or load locks connected to or interfaced with a specific system.

[0222] In addition to a semiconductor processing tool controller, the sensor-equipped wafer discussed herein may also include a controller configured to enable data to be collected from the one or more sensors on the sensor-equipped wafer and to communicate with, for example, the controller of the semiconductor processing tool (or another external controller) to receive commands from the semiconductor processing tool and / or send data to the semiconductor processing tool.

[0223] In general, a controller may be defined as an electronic device having various integrated circuits, logic, memory, and / or software that receive instructions, issue instructions, control operations, enable cleaning operations, enable endpoint measurements, etc. The integrated circuits may include chips in the form of firmware that store program instructions, digital signal processors (DSPs), chips defined as application specific integrated circuits (ASICs), and / or one or more microprocessors, or microcontrollers that execute program instructions (e.g., software). The program instructions may be instructions sent to the controller in the form of various individual settings (or program files) that define operating parameters for performing a particular measurement operation or calibration operation using a wafer equipped with a sensor.

[0224] In some implementations, the controller may be part of or coupled to a computer that is integrated with the system, coupled to the system, otherwise networked to the system, or a combination thereof. For example, the controller may be in the "cloud" or may be all or part of a wafer fab host system that may allow remote access to wafer processing. The computer may enable remote access to the system to monitor the current progress of measurement or calibration operations using sensor-equipped wafers, check the history of measurement or calibration operations using sensor-equipped wafers in the past, and check trends or performance metrics from multiple sensor-equipped wafer measurements from different semiconductor processing tools. In some examples, a remote computer (e.g., a server) may provide a processing recipe to the system via a network (which may include a local network or the Internet). The remote computer may include a user interface that enables input or programming of parameters and / or settings, which are then sent from the remote computer to the system. In some examples, the controller receives instructions in the form of data that specify parameters for each measurement or calibration process step to be performed during one or more sensor-equipped wafer operations. It should be understood that the parameters may be specific to the type of measurement to be performed and the type of tool the controller is configured to interface with or control the sensor-equipped wafer. Thus, as described above, the controller may be distributed, for example, by including one or more discrete controllers that are networked together and work toward a common purpose (e.g., processing and control as described herein). An example of a distributed controller for such a purpose is one or more integrated circuits on a chamber that communicate with one or more integrated circuits remotely (e.g., at a platform level or as part of a remote computer), which combine to control processing on the chamber.

[0225] Without limitation, the sensor-equipped wafers may be used in exemplary systems, which may include plasma etching chambers or modules, deposition chambers or modules, spin rinse chambers or modules, metal plating chambers or modules, cleaning chambers or modules, chamfer edge etching chambers or modules, physical vapor deposition (PVD) chambers or modules, chemical vapor deposition (CVD) chambers or modules, atomic layer deposition (ALD) chambers or modules, atomic layer etching (ALE) chambers or modules, ion implantation chambers or modules, track chambers or modules, and any other semiconductor processing system that may be associated with or used for the manufacture and / or preparation of semiconductor wafers.

[0226] As described above, depending on one or more processing steps to be performed by the sensor-equipped wafer and / or tool, the controller may communicate with one or more other tool circuits or modules, other tool components, cluster tools, other tool interfaces, adjacent tools, neighboring tools, tools located throughout the factory, a host computer, another controller, or a tool used in the transport of materials used to transport wafer containers to and from tool locations and / or load ports in a semiconductor manufacturing facility. For example, the controller may communicate with a remote system that can assign a sensor-equipped wafer to a particular tool, such as by FOUP, to allow the sensor-equipped wafer to be used within that tool to obtain measurements or data about various aspects of that tool.

[0227] It should be understood that the techniques discussed herein involving the use of sensor-equipped wafers can be practiced by one or more controllers, such as a controller located on the sensor-equipped wafer itself, or (in many cases) a controller located on the sensor-equipped wafer itself in combination with a separate controller (e.g., a controller associated with a semiconductor processing tool). Such controllers can be collectively or collectively configured to perform the techniques discussed herein.

[0228] In understanding the possibility of such a distributed processing arrangement, the term "jointly" as used herein to refer to memory devices and / or processors or various other items should be understood to indicate that the collection of items mentioned has characteristics or provides functions related to the collection. For example, if the server and client devices jointly store instructions that cause A, B, and C to occur, this includes at least the following situations: a) The server stores the instructions that cause A, B, and C to occur, but the client device does not store the instructions that cause A, B, and C to occur. b) The client device stores the instructions that cause A, B, and C to occur, but the server does not store the instructions that cause A, B, and C to occur. c) The server stores instructions that cause a specific subset of A, B, and C to occur (e.g., A and B but no C), and the client device stores instructions that cause a different specific subset of A, B, and C to occur (e.g., C but no A and B), wherein the instructions that cause each of A, B, and C to occur are stored separately on either or both of the client device and the server. d) The server stores instructions that cause a subset of A, B, and C to occur (e.g., A and B but no C), and the client device stores instructions that cause a different subset of A, B, and C to occur (e.g., B and C but no A), wherein the instructions that cause each of A, B, and C to occur are stored separately on either or both of the client device and the server. e) The server stores instructions that cause A and part of B to occur, and the client device stores instructions that cause C and the remainder of B to occur.

[0229] In all of the above situations, instructions for causing A, B and C to occur are stored jointly between the server and the client device, that is, such instructions are stored on one or two devices and it should be understood that the use of the term "jointly" (e.g., the server and the client device jointly store instructions that cause A, B and C to occur) covers all of the above situations and additional similar situations.

[0230] Similarly, a set of processors (eg, one or more processors of the first group and one or more processors of the second group) may be caused to jointly perform one or more actions, such as actions A, B, C, D, and D. B and C. As in the previous example, various permutations fall into this "common" language: a) One or more processors of the first group may be caused to execute each of A, B, and C, while one or more processors of the second group may not execute any of A, B, or C. b) The one or more processors of the second group may be caused to execute each of A, B, and C, while the one or more processors of the first group may not execute any of A, B, or C. c) One or more processors of the first group may be caused to execute a specific subset of A, B, and C, while one or more processors of the second group may be caused to execute a different specific subset of A, B, and C to be executed, so that between the two groups of processors, all of A, B, and C are executed. d) One or more processors of the first group may be enabled to execute part of A and B, and one or more processors of the second group may be enabled to execute the rest of C and B.

[0231] The term "wafer" as used herein may refer to a semiconductor wafer or substrate or other similar types of wafers or substrates; in the context of a wafer equipped with sensors, the wafer may also be made of other materials (eg, carbon fiber).

[0232] It should also be understood that the use of ordinal numbers herein, such as (a), (b), (c), ..., is for organizational purposes only and is not intended to convey any particular order or importance to the items associated with each ordinal number. For example, "(a) obtaining information related to speed; and (b) obtaining information related to position" should include obtaining information related to position before obtaining information related to speed, obtaining information related to speed before obtaining information related to position, and obtaining information related to position while obtaining information related to speed. Nevertheless, there may be situations where certain items associated with ordinal numbers may require a specific order, for example, "(a) obtaining information about speed, (b) determining acceleration based on information about speed, and (c) obtaining information about position"; in this example, (a) requires (b) to be performed because (b) depends on the information obtained in (a), but (c) may be performed before or after either (a) or (b).

[0233] It should be understood that phrases such as "for each of the one or more <items>" or "of each <item>" <item>)" (if used in this document) should be understood to include both single groups of items and multiple groups of items, that is, the use of the phrase "for...each" means that it is used in the programming language to refer to each item in the entire group of items referred to. For example, if the group of items referred to is a single item, then "each" will only refer to that single item (despite the fact that the dictionary definition of "each" is often defined as "each of two or more things"), and does not mean that there must be at least two of these items. Similarly, when a selected item can have one or more sub-items and a selection is made of one of these sub-items, it should be understood that in the case where the selected item has one and only one sub-item, selecting that one sub-item is inherently selecting the item itself.

[0234] It should also be understood that reference to a plurality of controllers that are generally configured to perform a variety of functions is intended to encompass situations where only one of the controllers is configured to perform all of the functions disclosed or discussed, as well as situations where various controllers each perform a subset of the functions discussed. For example, an auto-calibration wafer may include a controller that is configured to: control the operation of various sensors on the auto-calibration wafer and communicate data from the sensors to another controller associated with a semiconductor processing tool; the semiconductor processing tool controller may then analyze such data to determine various operating parameters for use with the semiconductor processing tool.

[0235] Various modifications to the embodiments described in this disclosure will be apparent to those skilled in the art, and the general principles defined herein may be applied to other embodiments without departing from the spirit or scope of the disclosure. Therefore, the claims are not intended to be limited to the embodiments presented herein, but should be given the broadest scope consistent with the disclosure, principles, and novel features disclosed herein.

[0236] Certain features in this specification described in the context of separate implementations may also be implemented in combination in a single embodiment. Conversely, various features described in the context of a single embodiment may also be implemented individually in multiple embodiments or in any suitable subcombination. Furthermore, while features may be described above as acting in certain combinations and even initially claimed, one or more features from a claimed combination may in some cases be deleted from that combination, and a claimed combination may be directed to subcombinations or variations of subcombinations.

[0237] Similarly, although operations are depicted in a particular order in the accompanying drawings, this should not be construed as requiring these operations to be performed in the particular order shown or in a continuous order, or to perform all the operations shown to achieve the desired result. In addition, the accompanying drawings can schematically depict another example process in the form of a flow chart. However, other operations that are not depicted can be incorporated in the schematically illustrated example process. For example, one or more additional operations can be performed before, after, simultaneously or between any illustrated operations. In some cases, multitasking and parallel processing may be advantageous. In addition, the separation of various system components in the above-described embodiments should not be construed as requiring such separation in all embodiments, and should be understood that the program components and the system can be generally integrated together or packaged into multiple software products in a single software product. In addition, other embodiments all fall within the scope of the following claims. In some cases, the actions described in the claims can be performed in different orders and still achieve the desired result.< / item>

Claims

1. An apparatus for evaluating characteristics of a semiconductor processing tool or component, the apparatus comprising: a base structure sized to be inserted through an opening of the semiconductor processing tool, the opening sized to receive a wafer for processing and transportable between at least two locations in the semiconductor processing tool by an object transport apparatus of the semiconductor processing tool, the base structure having a first side configured to contact and be supported by a portion of the object transport apparatus and a second side facing in a direction opposite the first side; one or more optical sensors, each optical sensor oriented so as to have an upward-facing field of view when the base structure is oriented with the first side facing downward; a controller, wherein the controller is communicatively coupled to each of the one or more optical sensors; as well as A power source is configured to provide power to at least the controller. 2 . The apparatus of claim 1 , wherein at least one of the one or more optical sensors is an imaging sensor.

3. The apparatus of claim 1, wherein at least one of the one or more optical sensors is coupled to a corresponding one or more lenses, the one or more lenses providing a field of view of at least 30° for the optical sensor.

4. An apparatus according to claim 2 or claim 3, wherein the apparatus has two or more optical sensors, the two or more optical sensors being distributed on the apparatus to have overlapping fields of view relative to a focal plane parallel to the second side and located at a first distance from the second side. The apparatus of claim 4 , wherein the first distance is between 2 mm and 100 mm.

6. The device according to claim 5, wherein the area formed by the intersection of the focal plane and the field of view of the optical sensor has a width of The semiconductor processing tool may be configured to process a plurality of wafers having a total area of ​​at least 15% of the total area of ​​the semiconductor processing tool, wherein d is a nominal wafer diameter of wafers that the semiconductor processing tool is configured to process.

7. An apparatus as claimed in claim 2 or claim 3, wherein there are a plurality of optical sensors and at least two of the optical sensors are located at different distances from a centre point of the base structure.

8. The apparatus according to any one of claims 1 to 3, further comprising: a first support structure rotatably coupled to the base structure; as well as A first rotation drive is configured to rotate the first support structure about a first rotation axis and relative to the base structure in response to receiving one or more first control signals, wherein at least one of the one or more optical sensors is directly or indirectly supported by the first support structure and is located a certain distance away from the first rotation axis in a direction perpendicular to the first rotation axis.

9. The apparatus of claim 8, wherein there are a plurality of optical sensors supported directly or indirectly by the first support structure, and at least two of the optical sensors supported by the first support structure are located at different distances from the first rotation axis.

10. The apparatus of claim 9, wherein the first axis of rotation is nominally centered on the base structure.

11. The apparatus of claim 9, wherein the first axis of rotation is offset from a center of the base structure.

12. The apparatus according to claim 11, further comprising: a second support structure rotatably coupled to the first support structure; as well as a second rotational drive configured to rotate the second support structure about a second rotational axis and relative to the first support structure in response to receiving one or more second control signals, wherein: The second supporting structure is supported by the first supporting structure, The at least one of the one or more optical sensors is supported by the second support structure, and The second rotation axis is radially offset from the first rotation axis.

13. The apparatus of any one of claims 1 to 3, wherein a maximum dimension of the base structure is 50% or less of a nominal wafer diameter of a wafer that the semiconductor processing tool is configured to process.

14. The apparatus according to any one of claims 1 to 3, wherein: The maximum dimension of the base structure is 50% or less of 300 mm, and At least one of the one or more optical sensors is disposed on the base structure at a position offset from a central axis of the base structure perpendicular to the second side.

15. The apparatus of claim 13, wherein there are a plurality of optical sensors and one of the optical sensors is located near the central axis of the base structure.

16. The apparatus according to any one of claims 1 to 3, further comprising a first optical projection unit configured to project a first illumination pattern along a first axis, wherein: The first axis is inclined at an angle relative to the second side, The first axis intersects a reference plane, the reference plane is parallel to the second side and offset from the second side by a first distance, The first side is further from the reference plane than the second side, and The one or more optical sensors are positioned such that at least some locations where the reference plane intersects the first illumination pattern are within a total field of view of the one or more optical sensors.

17. The apparatus of claim 16, wherein the first illumination pattern intersects the reference plane along a first line.

18. The device according to claim 17, further comprising a second optical projection unit, wherein: The second optical projection unit is configured to project a second illumination pattern along a second reference plane, the second reference plane being perpendicular to the second side and parallel to the first line, the first illumination pattern intersecting the reference plane along the first line, and The second illumination pattern intersects the reference plane along a second line parallel to the first line.

19. The apparatus of claim 16, wherein the first illumination pattern intersects the reference plane at a plurality of discrete locations distributed on the reference plane.

20. The apparatus of any one of claims 1 to 3, further comprising an inductive charging coil coupled to the power source.

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