MEMS-based gas control module and semiconductor device using same

Abstract

The present invention relates to the technical field of semiconductor devices, and provides a MEMS-based gas control module, a construction method and a semiconductor device using the gas control module. The gas control module comprises: a first substrate, on which a plurality of first micro-valve arrays are provided, wherein a plurality of reaction gases flow into the gas control module through the first micro-valve arrays; and a second substrate, on which a plurality of second micro-valve arrays are provided, wherein the plurality of reaction gases are mixed between the first substrate and the second substrate and then flow out of the gas control module through the second micro-valve arrays. The present invention utilizes MEMS and semiconductor packaging technology to optimize the structure of a gas panel, so as to obtain a gas panel having a smaller size, thereby enabling more extensive multi-path gas flow partition control within a reaction cavity.

Description

A MEMS-based gas control module and its application in semiconductor devices. Technical Field

[0001] This invention generally relates to the field of semiconductor device technology. Specifically, this invention relates to a MEMS-based gas control module, its construction method, and its application in semiconductor devices. Background Technology

[0002] Vacuum Coupling Radius Seal (VCR) connectors are a type of metal gasket face seal fitting widely used in semiconductor equipment. Figure 1 shows a schematic diagram of a VCR connector in the prior art. As shown in Figure 1, the sealing element of the VCR connector uses a metal gasket. The gasket is compressed by the interlocking of internal and external threads, causing a certain deformation of the gasket, thereby achieving a sealing effect.

[0003] Since a pair of VCR connectors is required between every two components, the VCR connectors occupy a large amount of lateral space between components such as valves. As semiconductor equipment becomes larger and more multi-cavity, the VCR connectors are gradually unable to meet the miniaturization requirements of semiconductor equipment.

[0004] For gas control devices, surface mount gas distribution module technology or modular technology can be used. Gas flows horizontally within a block, and gas control components such as valves and filters are surface-mounted onto the block to form a horizontal sealing surface. Sealing types include W-seals and C-seals. W-seals and C-seals are available in two different sizes: 1.125 inches and 1.5 inches, with widths of 28.5 mm and 39 mm respectively.

[0005] A gas panel (or gas box) is a key component in semiconductor equipment. It is primarily used to control gas pressure, reducing the pressure of the source gas to ideal specifications to ensure the gas is delivered at the correct flow rate and pressure. A gas panel typically includes multiple gas delivery devices (gas sticks). Within each gas delivery device, components such as the manual valve before the mass flow controller (MFC), pneumatic valve, filter, pressure indicator, pressure regulating valve, and tee typically occupy 7 to 8 bases, with a length of approximately 28.5×7 to 39×8 (200mm-320mm). The mass flow controller itself is approximately 90-110mm long. Figure 2 shows a schematic diagram of a gas panel in the prior art. As shown in Figure 2, this gas panel has 9 gas delivery devices and 3 slots for lateral connections such as tee valves. The panel surface length of the 9 gas delivery devices is approximately 400mm-500mm, and the width is 480-680mm. The current gas panel is insufficient to meet the demands of complex gas mixing and / or proportional distribution after mixing. To achieve this, up to three MFCs and numerous three-way and four-way valves are required for complex purging, typically increasing the gas holder length by 300mm. Replacing the current large MFC with smaller microelectromechanical systems (MEMS) microvalves (mere millimeters square) would significantly reduce the size of the gas panel (or gas box). However, continuing to use traditional modular gas systems (IGS) and VCR-based connections, along with conventional mechanical three-way and four-way valves connected to IGS / VCRs, becomes a bottleneck for gas panel integration (their large size prevents the panel from accommodating more gas paths, and the large dead zone of mechanical valves results in significant stagnant residential gas). Therefore, further development of MEMS-based three-way and four-way valves, as well as gas mixing and / or proportional distribution mechanisms, is needed to further reduce the size of the gas panel (or gas box) and improve its gas control accuracy. Summary of the Invention

[0006] To at least partially solve the aforementioned problems in the prior art, the present invention proposes a MEMS-based gas control module, comprising: a first substrate and a second substrate, wherein an intermediate cavity is formed between the first substrate and the second substrate.

[0007] The first substrate includes multiple first channels, each with a first micro-valve array at its first end and a second end connected to an intermediate cavity.

[0008] The second substrate includes multiple second channels. The first end of the second channel is connected to the intermediate cavity and is provided with a second micro-valve array. The second end of the second channel is an outlet, so that the gas in the intermediate cavity flows out through the second micro-valve array and the second channel.

[0009] In one embodiment of the invention, a plurality of first microvalve arrays are configured to perform mass flow control on a variety of reaction gases; and / or

[0010] Multiple arrays of second microvalve are configured to control the mass flow rate or flux of the mixed reaction gas.

[0011] In one embodiment of the present invention, the mass flow control principle is specified to be thermal or pressure-based.

[0012] In one embodiment of the present invention, the MEMS-based gas control module further includes:

[0013] A housing, the housing surrounding or disposed between the first substrate and the second substrate; and / or

[0014] A shut-off valve is disposed below the first channel and / or the second channel.

[0015] In one embodiment of the present invention, the purge gas flows into the gas control module from the first channel and flows out of the gas control module from the first channel or the second channel.

[0016] In one embodiment of the present invention, the first microvalve array and the second microvalve array include diaphragm valves or cantilever beam diaphragm valves.

[0017] In one embodiment of the present invention, the MEMS-based gas control module further includes:

[0018] The control system is configured to control the opening and closing of the first microvalve array and the second microvalve array.

[0019] In one embodiment of the present invention, the MEMS-based gas control module further includes:

[0020] A gas stirring device is arranged in the intermediate cavity, and the gas stirring device is configured to accelerate the mixing of multiple reactive gases.

[0021] In one embodiment of the present invention, the first substrate and / or the second substrate are formed by bonding multiple wafers.

[0022] In one embodiment of the present invention, the MEMS valve and the smaller gas mixing or proportioning cavity based on MEMS bonding or encapsulation are specified to have a feature size of 5 mm to 10 micrometers.

[0023] In one embodiment of the present invention, the control accuracy of the MEMS-based gas control module is improved by 1 to 12 orders of magnitude.

[0024] In one embodiment of the invention, a passive mixing unit and / or an active mixing unit are further provided inside and / or around the MEMS-based gas control module.

[0025] Passive mixing units are wedge-shaped inlets, Z-shaped channels, three-dimensional serpentine channel structures, inlaid structures, twisted channels, and chemical surfaces set in channels or intermediate cavities;

[0026] The active mixing unit is a sound wave generating device, pressure disturbance applying device, magnetic field generating device, electric field generating device, and heater installed inside or outside the channel or intermediate cavity.

[0027] In one embodiment of the present invention, the MEMS-based gas control module further includes pressure and temperature sensors disposed within the MEMS-based gas control module.

[0028] In one embodiment of the present invention, the parameters measured by the pressure and temperature sensor include at least the upstream pressure of the valve, the pressure and temperature between the substrates, and the downstream pressure of the valve.

[0029] The present invention also proposes a semiconductor device, comprising:

[0030] Multiple air intake lines connect to multiple gas control modules;

[0031] Multiple gas control modules, specifically the MEMS-based gas control module, wherein various reactive gases flow into the gas control module through inlet pipes for mixing; and

[0032] A reaction chamber, which is connected to the gas control module, wherein the mixed reaction gas enters the reaction chamber from the gas control module and reacts on the substrate to be processed.

[0033] In one embodiment of the present invention, the semiconductor device further includes:

[0034] An intake module, wherein multiple intake pipes are connected to multiple gas control modules via the intake module; and

[0035] The gas outlet module contains purge gas that flows from multiple gas control modules to the gas outlet module.

[0036] The present invention has at least the following beneficial effects: The present invention proposes a MEMS-based gas control module, a construction method and its application in semiconductor devices, wherein the structure of the gas panel is optimized by using MEMS and semiconductor packaging technology, which can obtain a smaller gas panel, thereby enabling a larger number of multi-channel airflow partition control in the reaction chamber.

[0037] Simultaneously, due to the use of higher-precision MEMS valves and smaller gas mixing or proportioning cavities constructed based on MEMS bonding or encapsulation, the characteristic size is 5mm-10 micrometers, resulting in a 1-12 order of magnitude improvement in gas control accuracy. In this invention, "characteristic size" can be understood as "characteristic length," where, for an object, the characteristic length typically refers to a representative length. For example, if the three-dimensional structure of a key component of a MEMS-based gas control module is approximately spherical, the characteristic size refers to the radius or diameter of that sphere; or if the three-dimensional structure of a key component of a MEMS-based gas control module is approximately cuboid, the characteristic size refers to the length, width, or height of that cuboid. The characteristic size of a key component in a prior art gas panel is 1.125 inches, while the characteristic size of a MEMS-based gas control module is 5mm-10 micrometers. Since the unit of gas flow mass flow rate is SCCM or SLM, a 1-order-of-magnitude decrease in characteristic size means a 3-order-of-magnitude improvement in control accuracy; 100-micrometer-level MEMS can provide up to a 12-order-of-magnitude improvement in accuracy. That is, when the control accuracy of the existing technology is 1 SCCM, the feature size decreases by one order of magnitude, and the control accuracy becomes 1 / 10. 3 SCCM. Attached Figure Description

[0038] To further illustrate the advantages and other features of the various embodiments of the present invention, a more specific description of the embodiments of the present invention will be presented with reference to the accompanying drawings. It is understood that these drawings depict only typical embodiments of the invention and are therefore not intended to limit its scope. In the drawings, identical or corresponding parts will be indicated by the same or similar reference numerals for clarity.

[0039] Figure 1 shows a schematic diagram of a VCR connector in the prior art.

[0040] Figure 2 shows a schematic diagram of the structure of a gas panel in the prior art.

[0041] Figures 3A-D show schematic diagrams of the functional modules of the gas panel.

[0042] Figures 4A-C show the PID diagrams of a MEMS-based gas control module in one embodiment of the present invention.

[0043] Figures 5A-C show schematic diagrams of the working state of a MEMS-based gas control module in one embodiment of the present invention.

[0044] Figure 6 shows a PID diagram of a semiconductor device in one embodiment of the present invention.

[0045] Figures 7A-D show a three-dimensional structural schematic diagram of a MEMS-based gas control module in one embodiment of the present invention.

[0046] Figure 8 shows a schematic diagram of the structure of a semiconductor device in one embodiment of the present invention.

[0047] Figure 9 shows a cross-sectional schematic diagram of a hybrid unit according to an embodiment of the present invention. Detailed Implementation

[0048] It should be noted that the components in the various figures may be shown exaggeratedly for illustrative purposes and are not necessarily to scale. In each figure, the same reference numerals are used for components that are identical or have the same function.

[0049] In this invention, unless otherwise specified, "arranged on," "arranged above," and "arranged on" do not exclude the possibility of an intermediate element between them. Furthermore, "arranged on or above" merely indicates the relative positional relationship between two components, and in certain cases, such as when the product orientation is reversed, it can also be converted to "arranged below or under," and vice versa.

[0050] In this invention, the various embodiments are merely intended to illustrate the solutions of the invention and should not be construed as limiting.

[0051] In this invention, unless otherwise specified, the quantifiers “a” and “one” do not exclude scenarios involving multiple elements.

[0052] It should also be noted that, in the embodiments of the present invention, only a portion of the components or parts may be shown for clarity and simplicity. However, those skilled in the art will understand that, under the teachings of the present invention, necessary components or parts can be added as needed for specific scenarios. Furthermore, unless otherwise stated, features in different embodiments of the present invention can be combined with each other. For example, a feature in the second embodiment can replace a corresponding or functionally identical or similar feature in the first embodiment, and the resulting embodiment will also fall within the scope of disclosure or description of this application.

[0053] It should also be noted here that within the scope of the present invention, terms such as "identical", "equal", "equivalent" do not mean that the two values are absolutely equal, but allow for a certain reasonable error. That is to say, such terms also cover "substantially identical", "substantially equal", "substantially equivalent". By analogy, in the present invention, terms indicating direction such as "perpendicular to", "parallel to", etc. also cover the meanings of "substantially perpendicular to", "substantially parallel to".

[0054] In addition, the numbering of the steps of each method of the present invention does not limit the execution order of the method steps. Unless specifically stated, the method steps can be executed in different orders.

[0055] The present invention will be further described below in conjunction with the specific embodiments with reference to the accompanying drawings.

[0056] In a traditional semiconductor device such as the gas panel or gas box (Gas Box) shown in Figure 2, the gas path is usually relatively simple and there is no multi-path gas mixing. A single gas flows directly into the reaction chamber after passing through the stop valve, pressure regulating valve, MFC, and stop valve. If it is a deflagration or toxic gas, a three-way valve for purging gas needs to be connected.

[0057] However, in an epitaxial device, precise mixing of multiple gases is usually required. In such a gas path, gases A, B, and even C have their own independent MFCs, injecting gases with flow rates of Qa, Qb, and / or Qc into the converging main pipe. The total flow rate of the mixed gas is Qtotal = Qa + Qb + Qc. A mixing mass flowmeter (MFCmix) can be set to control the gas with a flow rate of Qmix (Qmix < Qtotal) to enter the downstream gas path, and the excess flow rate is discharged through the bypass pipeline.

[0058] Furthermore, in order to precisely control the process, the same gas injected into the reaction chamber can be divided into zones for control, that is, the single-path gas is split into multiple paths of gas through the MFC and injected into the reaction chamber through different injection points. In the case of gas mixing, N proportional control flowmeters are set below the mixing mass flowmeter. At this time, the number of MFCs is N + 4 (MFC a b c + MFC mix + n × Proportional MFC), while if independent gas mixing is carried out from N injection points, 4N MFCs are required (n × (MFC a b c + MFC mix)). In comparison, the number of MFCs can be reduced by 3N - 4.

[0059] Gas control panels are typically divided into multiple layers according to the gas intake sequence. Figures 3A-D show schematic diagrams of the functional modules of a gas control panel, where CV represents a check valve, MV represents a manual valve, GF represents a gas filter, PV represents a pneumatic valve, RG represents a regulator, GA represents a pressure gauge, and MFC represents a mass flow controller. As shown in Figure 3A, the first layer includes a pneumatic / manual check valve, a manual pressure reducing valve, a pressure gauge, and / or a filter, and may also include a three-way or four-way valve for purging. As shown in Figure 3B, the second layer includes MFCa, MFCb, and MFCc, used for the initial mass flow measurement. As shown in Figure 3C, the third layer includes a mixed-gas mass flow meter for mixed-gas mass flow measurement. As shown in Figure 3D, the fourth layer includes a proportional control flow meter or a gas proportional distributor for multi-channel distribution of a single gas stream. The fifth layer includes shut-off valves or atomic layer deposition (ALD) valves.

[0060] In this invention, by integrating MEMS temperature sensors, MEMS pressure sensors, MEMS shut-off valves, and MEMS proportional control valves in three dimensions at the wafer level, an ultra-small gas panel for semiconductor devices with full functionality can be obtained. This eliminates the need for integration via traditional VCR connectors and metal pipes, or by surface-mount W-shaped or C-shaped seals.

[0061] In this invention, all shut-off valves or proportional control valves are located on a MEMS substrate (the MEMS substrate can be a wafer or a bonded combination of multiple wafers). The proportional control valves and shut-off valves can be arranged in pairs on opposite sides of the same substrate. At least two layers of proportional control valves form a closed space connecting multiple valves through wafer bonding or packaging technology. This space and the valves located on its upper and lower surfaces enable proportional mixing of multiple gases, mass flow control of the mixed gas, purging and displacement functions, and / or the three-way and four-way functions required for purging, displacement, and mixing.

[0062] Pressure and temperature sensors are integrated into the space formed by two substrates to obtain the device's temperature and the pressure upstream and downstream of the valve, enabling control based on standard thermal or pressure-based mass flow principles. Furthermore, since pressure-based MFCs eliminate the need for heaters and laminar flow elements, this invention prefers to use the pressure principle for control, i.e., in choked flow conditions (P... 上游 >2P 下游 The flow rate is proportional to P. 上游In non-blocking flow, the flow rate is proportional to the square difference between the upstream and downstream pressures.

[0063] In this invention, the parameters measured by these sensors include at least upstream pressure, inter-substrate pressure and temperature, and downstream pressure.

[0064] Figures 4A-C illustrate a schematic diagram (PID diagram) of the piping and instrumentation of a MEMS-based gas control module according to an embodiment of the present invention. As shown in Figure 4A, the device has a multi-gas proportioning function and is capable of mass flow control and purging / replacement of the mixed gases. The device includes a first substrate 410, a second substrate 420, and a housing 430. The housing 430 surrounds the first substrate 410 and the second substrate 420 or is disposed between the first and second substrates to form an intermediate cavity 440 between the first substrate 410 and the second substrate 420. The first substrate 410 includes a plurality of first channels, the first end of which is provided with a first micro-valve array 450, and the second end of which opens to the intermediate cavity 440, allowing multiple reactant gases to flow into the intermediate cavity 440 for mixing through the first micro-valve array and the first channels. The second substrate 420 is located below the first substrate 410 and includes a plurality of second channels. The first end of the second channel is connected to the intermediate cavity and is provided with a second micro-valve array 460. The second end of the second channel is an outlet, allowing gas in the intermediate cavity 440 to flow out through the second micro-valve array 460 and the second channel. As shown in Figure 4B, the device further adds shut-off valves 470 and 480. As shown in Figure 4C, the device only provides shut-off valve 480 at the second substrate, and the shut-off valve 470 at the first substrate can be omitted. In this invention, the gas control module can achieve an integrated design of gas mixing and three-way purge valve through chip-to-chip bonding, high-purity ceramic / metal packaging, and metal sealing gaskets. Therefore, the housing 430 can be a sidewall structure for sealing and bonding the first and second substrates. Alternatively, the housing 430 can be a separate sealing housing to enclose the first and second substrates.

[0065] The following description uses the MEMS-based gas control module shown in Figure 4A as an example to illustrate its working mode. Figures 5A-C show schematic diagrams of the working state of the MEMS-based gas control module in one embodiment of the present invention. As shown in Figure 5A, in the gas mixing mode, the micro-valve arrays at the inlets of gas A and gas B, as well as the micro-valve arrays at the outlets leading to the cavity, injection port, or shower head, are open. Gas A and gas B flow in from the inlets, mix in the intermediate cavity, and flow to the cavity, injection port, or shower head. As shown in Figures 5B-C, in the purging mode, the micro-valve arrays at the inlets of the incoming gas and purging gas, as well as the micro-valve arrays at the purging gas outlets of the first substrate or the second substrate, are open. Purging gas flows in from the inlets and flows out from the outlets of the first substrate or the second substrate. Since the gas mixing process is a superposition of mass flow control and three-way / four-way / multi-way functions, and the purging process is a simplified gas mixing process that does not include proportional mixing but only multi-way functions, they can be integrated into the same module. The micro-valve arrays in this device can be arranged in an interleaved manner to improve the efficiency of gas mixing or purging. The micro-valve array can be a diaphragm valve or a cantilever beam diaphragm valve, and its opening and closing are controlled by a software-driven control system.

[0066] Figure 6 shows a PID diagram of a semiconductor device in one embodiment of the present invention. As shown in Figure 6, the main inlet pipe of a single device or a single reaction chamber can be a standard 3 / 8, 1 / 4, or 1 / 8 pipe, using VCR or IGS devices and connections, leading downwards into multiple MEMS-based gas control modules. Due to the presence of the MEMS microvalve array, the flow rate of the microvalve array depends on the number of microvalves or the area of ​​the microarray, i.e., at least one times the flow rate of the microvalve array (area) is required before and after gas separation. A gas separation strategy of 1 to N does not reduce the number of microvalves; the simplest and most effective method is to use N sets of gas mixing structures for N sets of individual control. Gases A and B, as well as the carrier gas (purge gas), enter the mixing space between the first substrate and the second substrate through conventional manual shut-off valves, pneumatic shut-off valves, filters, and pressure regulating valves via gas separation pipes. The first substrate is provided with multiple first proportional control valves for mass flow control of the gas before mixing. The second substrate is provided with multiple second proportional control valves for mass flow control or flow rate control of the mixed gas. A gas stirring and disturbance structure can be provided between the first substrate and the second substrate to help accelerate mixing. A shut-off valve can be installed below the first proportional control valve and / or the second proportional control valve to ensure gas cut-off. This structure allows for the connection of all gas panels and gas boxes on semiconductor (flat panel, LED, solar energy, and other general semiconductor technologies) equipment using traditional VCR or IGS structures.

[0067] Devices to promote gas mixing can also be placed inside and / or around the MEMS-based gas control module. Mixing technologies are divided into passive and active: in the formation of MEMS structures, passive mixing can well meet the requirements due to its larger specific surface area compared to traditional VCR / IGS technologies. Simultaneously, MEMS fabrication technology can effectively realize these passive fluid disturbance structures.

[0068] "Active" mixing is another important type of mixing. In active mixing, mixing efficiency is increased by applying external forces to the sample. To obtain an active mixing scheme, special transducers need to be incorporated into this invention. Different physical means are involved in achieving "active" mixing of fluids: sound waves, pressure disturbances, electromagnetic fields, and heating methods. MEMS actuation technology can also effectively provide these necessary physical fields.

[0069] Active mixing processes involve various physical methods: sound waves, pressure disturbances, magnetic fields, and thermal methods. For example, sound waves enhance mixing; however, the external energy required for active mixing can lead to side effects, such as the heating effect of sound waves causing potential decomposition / deposition of the gas / precursor. Therefore, the appropriate active mixing driving method and energy level must be carefully selected based on the gas being used. Thus, when a passive method can meet the mixing requirements, it should be preferred.

[0070] Based on the passive and active mixing technologies described above, passive and active mixing units can be placed inside and / or around a MEMS-based gas control module. Passive mixing units can be wedge-shaped inlets, Z-shaped channels, three-dimensional serpentine channel structures, inlaid structures, twisted channels, or chemical surfaces located within channels or intermediate cavities. Active mixing units can be acoustic wave generators, pressure disturbance application devices, magnetic field generators, electric field generators, heaters, etc., located inside or outside channels or intermediate cavities.

[0071] Figure 9 shows a cross-sectional schematic diagram of a mixing unit according to an embodiment of the present invention. As shown in Figure 9, at the outlet of the second substrate, a spiral or other twisted or elongated flow channel structure is provided around the outlet, such that the path of the insufficiently mixed gas is prolonged and / or the disturbance is increased.

[0072] The hybrid unit can be fabricated by etching, or fabricated on a third substrate and then assembled onto a first or second substrate by bonding or other means.

[0073] Figures 7A-D show three-dimensional structural diagrams of a MEMS-based gas control module according to one embodiment of the present invention. Figure 7A shows the three-dimensional structure of a gas control module with a shut-off valve on the back side of the substrate; the structure at the top of the gas control module for distributing the three gases is omitted. Figure 7B shows the three-dimensional structure of a gas control module without a shut-off valve on the back side of the substrate, where the partial structure at the top of the gas control module for distributing the three gases can be seen. Figure 7C shows a perspective view of the top of the gas control module, showing the entry channels for the three different gases. Figure 7D shows a three-dimensional perspective view of the top of the gas control module, showing the entry channels for the three different gases and the proportional control valve at the first substrate.

[0074] As shown in Figures 7A-D, a shut-off valve may or may not be installed on the back of the substrate of the gas control module. The gas entering the gas control module can be divided into three groups, allowing for either three-way gas mixing or two-way gas mixing. The third valve is used for purging or purging exhaust. Purging exhaust can be performed using either the upper or lower valves. Since the lower exhaust port is usually closer to the cavity, directly facing the shower head or injector of the reaction chamber, it is more reasonable to place the purging exhaust port at the upper position. Without considering the packaging shell, the area of ​​the substrate in the gas control module can be controlled to 10mm × 10mm, which can achieve the functions of the second, third, and fourth layers of a traditional gas panel with a maximum flow rate of 20-80 SLM.

[0075] Figure 8 shows a schematic diagram of a semiconductor device according to one embodiment of the present invention. As shown in Figure 8, each gas control module may have an overlapping sealing structure, allowing multiple reactive gases to flow through the top gas distribution plate to the first micro-valve array on the first substrate. After mixing, the reactive gases flow from the second micro-valve array on the second substrate to the reaction chamber. Specifically, the head-end module (inlet module) and the tail-end module (outlet module) respectively handle inlet and outlet gases, while the intermediate gas control modules can overlap to handle inlet and outlet gases. The intermediate gas control modules outlet gases downward through the second substrate, forming a mixed gas output to the injection point of the reaction chamber. In Figure 8, the two intermediate gas control modules correspond to the nozzles of the two injection points, mixing the three sets of reactive gases by mass flow rate and then outputting two independent gases. Furthermore, multiple intermediate gas control modules can be connected to provide more independent mixed gas injection points, where each gas control module has a complete purging function. A gas control module can be 10mm wide, corresponding to a 12-inch semiconductor substrate, and can provide more than 30 independently controlled mass flow mixing injection points in a single dimension. In addition, the number of VCR or IGS pipelines can be minimized. In Figure 8, the reaction gases A, B, and C correspond to three gas delivery devices.

[0076] In summary, this invention allows for the use of conventional techniques to arrange pneumatic / manual shut-off valves, manual pressure reducing valves, pressure gauges, and / or filters in the first layer of a conventional gas panel. This is because the number of these components is small, with each gas in a chamber corresponding to one pipeline, and the usage does not increase with the complexity of the gas circuit. The purging tee or four-way valve in the first layer of the conventional gas panel can be integrated into a first substrate or other substrate that implements the second layer's functionality. The first substrate can perform the first mass flow rate measurement function of the second layer of the conventional gas panel. The first or second substrate can perform the mixed gas mass flow rate measurement function of the third layer of the conventional gas panel. The third substrate, or the combination of the first and second substrates, can perform the function of multi-channel distribution of a single gas stream by a proportional control valve in the conventional gas panel. The method using the first and second substrates reduces the number of module layers and topological complexity. The fourth substrate can perform the function of a shut-off valve or ALD valve in the conventional gas panel.

[0077] In this invention, the gas control module achieves an integrated design of gas mixing and a three-way purge valve through chip-to-chip bonding, high-purity ceramic / metal encapsulation, and metal sealing gaskets. A shut-off valve can also be added to prevent leakage. The multi-way valve, gas mixing, and proportional gas distribution structure is formed by two sets of micro-valve arrays and the space between them, achieving the functions of the original gas panel while significantly reducing its size and manufacturing cost.

[0078] This invention retains only the VCR or IGS piping in the first layer of a traditional gas panel. The purging function of the first layer and the functions of the second, third, and fourth layers of a traditional gas panel can be achieved through a gas control module, significantly reducing the volume, weight, and cost of the gas panel. Most reaction chambers use fewer than 10 types of gases, while advanced processes require more than 10 injection ports. The complexity of this combination would exponentially increase the number of valves required. However, this invention requires only a number of traditional IGS or VCR type valves that are proportional to the number of reactant gases. The upper and lower micro-valve arrays and the space between the micro-arrays constitute a multi-way valve, a gas mixing and even a proportional gas distribution structure, realizing the purging function of the first layer and the functions of the second, third, and fourth layers of the gas panel, significantly reducing the use of pressure reducing valves, manual valves, and pneumatic valves.

[0079] Simultaneously, due to the use of higher-precision MEMS valves and smaller gas mixing or proportioning cavities constructed based on MEMS bonding or encapsulation, the characteristic size is 5mm-10 micrometers, resulting in a 1-12 order of magnitude improvement in gas control accuracy. In this invention, "characteristic size" can be understood as "characteristic length," where, for an object, the characteristic length typically refers to a representative length. For example, if the three-dimensional structure of a key component of a MEMS-based gas control module is approximately spherical, the characteristic size refers to the radius or diameter of that sphere; or if the three-dimensional structure of a key component of a MEMS-based gas control module is approximately cuboid, the characteristic size refers to the length, width, or height of that cuboid. The characteristic size of a key component in a prior art gas panel is 1.125 inches, while the characteristic size of a MEMS-based gas control module is 5mm-10 micrometers. Since the unit of gas flow mass flow rate is SCCM or SLM, a 1-order-of-magnitude decrease in characteristic size means a 3-order-of-magnitude improvement in control accuracy; 100-micrometer-level MEMS can provide up to a 12-order-of-magnitude improvement in accuracy. That is, when the control accuracy of the existing technology is 1 SCCM, the feature size decreases by one order of magnitude, and the control accuracy becomes 1 / 10. 3 SCCM.

[0080] Although various embodiments of the invention have been described above, it should be understood that they are presented by way of example only and not as limitations. It will be apparent to those skilled in the art that various combinations, modifications, and alterations can be made without departing from the spirit and scope of the invention. Therefore, the breadth and scope of the invention disclosed herein should not be limited by the exemplary embodiments disclosed above, but should be defined solely by the appended claims and their equivalents.

Claims

1. A MEMS-based gas control module, characterized in that, include: A first substrate and a second substrate, wherein an intermediate cavity is formed between the first substrate and the second substrate. The first substrate includes multiple first channels, each with a first micro-valve array at its first end and a second end connected to an intermediate cavity. The second substrate includes multiple second channels. The first end of the second channel is connected to the intermediate cavity and is provided with a second micro-valve array. The second end of the second channel is an outlet, so that the gas in the intermediate cavity flows out through the second micro-valve array and the second channel.

2. The MEMS-based gas control module according to claim 1, characterized in that, Multiple first microvalve arrays are configured to perform mass flow control on a variety of reactive gases; and / or Multiple arrays of second microvalve are configured to control the mass flow rate or flux of the mixed reaction gas.

3. The MEMS-based gas control module according to claim 1, characterized in that, The mass flow control principle is either thermal or pressure-based.

4. The MEMS-based gas control module according to claim 1, characterized in that, Also includes: A housing that surrounds or is disposed between a first substrate and a second substrate; and / or A shut-off valve is disposed below the first channel and / or the second channel.

5. The MEMS-based gas control module according to claim 1, characterized in that, The purge gas flows into the gas control module from the first channel and flows out of the gas control module from either the first or second channel.

6. The MEMS-based gas control module according to claim 1, characterized in that, The first microvalve array and the second microvalve array include diaphragm valves or cantilever beam diaphragm valves.

7. The MEMS-based gas control module according to claim 1, characterized in that, Also includes: The control system is configured to control the opening and closing of the first microvalve array and the second microvalve array.

8. The MEMS-based gas control module according to claim 1, characterized in that, Also includes: A gas stirring device is arranged in the intermediate cavity, and the gas stirring device is configured to accelerate the mixing of multiple reactive gases.

9. The MEMS-based gas control module according to claim 1, characterized in that, The first substrate and / or the second substrate are formed by bonding multiple wafers.

10. The MEMS-based gas control module according to claim 1, characterized in that, MEMS valves and smaller mixing or proportioning cavities based on MEMS bonding or encapsulation, with feature dimensions of 5 mm to 10 micrometers.

11. The MEMS-based gas control module according to claim 10, characterized in that, The control accuracy of MEMS-based gas control modules is improved by 1 to 12 orders of magnitude.

12. The MEMS-based gas control module according to claim 1, characterized in that, It also includes passive mixing units and / or active mixing units, disposed inside and / or around the MEMS-based gas control module. Passive mixing units are wedge-shaped inlets, Z-shaped channels, three-dimensional serpentine channel structures, inlaid structures, twisted channels, and chemical surfaces set in channels or intermediate cavities; The active mixing unit is a sound wave generating device, pressure disturbance applying device, magnetic field generating device, electric field generating device, and heater installed inside or outside the channel or intermediate cavity.

13. The MEMS-based gas control module according to claim 1, characterized in that, It also includes pressure and temperature sensors housed within the MEMS-based gas control module.

14. The MEMS-based gas control module according to claim 13, characterized in that, The parameters measured by the pressure and temperature sensors include at least the upstream pressure of the valve, the pressure and temperature between the substrates, and the downstream pressure of the valve.

15. A semiconductor device, characterized in that, include: Multiple air intake lines connect to multiple gas control modules; Multiple gas control modules, which are MEMS-based gas control modules as described in any one of claims 1-14, wherein multiple reactive gases flow into the gas control modules through inlet pipes for mixing; and A reaction chamber, which is connected to the gas control module, wherein the mixed reaction gas enters the reaction chamber from the gas control module and reacts on the substrate to be processed.

16. The semiconductor device according to claim 15, characterized in that, Also includes: An intake module, wherein multiple intake pipes are connected to multiple gas control modules through the intake module; as well as The gas outlet module contains purge gas that flows from multiple gas control modules to the gas outlet module.

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