A MEMS-based gas control module and a semiconductor device to which the same is applied

Abstract

The application relates to the technical field of semiconductor equipment, and discloses a gas control module based on MEMS, a construction method and a semiconductor equipment applying the same. The gas control module comprises a first substrate, which is provided with a plurality of first micro-valve arrays, wherein a plurality of reaction gases flow into the gas control module through the first micro-valve arrays; and a second substrate, which is provided with a plurality of second micro-valve arrays, wherein the plurality of reaction gases flow out of the gas control module through the second micro-valve arrays after being mixed between the first substrate and the second substrate. The structure of the gas panel is optimized by using MEMS and semiconductor packaging technology, so that a gas panel with a smaller size can be obtained, and a larger number of multi-path gas flow partition controls can be performed on a reaction cavity.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of semiconductor equipment in general. In particular, the present application relates to a MEMS-based gas control module, a construction method thereof and a semiconductor equipment using the same. BACKGROUND

[0002] Vacuum Coupling Radius Seal (VCR) fitting is a kind of metal gasket face seal fitting, which is widely used in semiconductor equipment. Figure 1 A structure diagram of a VCR fitting in the prior art is shown. As Figure 1 shown, the sealing element of the VCR fitting uses a metal gasket, and the metal gasket is compressed by the interlocking of the inner and outer threads to produce a certain deformation, thereby achieving the sealing effect.

[0003] Since a pair of VCR fittings is required between each two elements, the VCR fitting will occupy a large amount of transverse space between the elements such as valves, and with the large-scale and multi-chamber of semiconductor equipment, the VCR fitting gradually cannot meet the miniaturization requirement of semiconductor equipment.

[0004] For the gas control device, Surface Mount gas distribution module technology or modular technology can be used, in which the gas flows horizontally in the block, and the gas control elements such as valves and filters are surface mounted on the block to form a horizontal sealing surface. The sealing types include W-seal and C-seal. The W-seal and C-seal have two different specifications of 1.125 and 1.5 inch, and the widths are 28.5 and 39 mm respectively.

[0005] The gas panel (or gas box) is a key component in semiconductor equipment, which is mainly used to control the gas pressure and reduce the pressure of the source gas to the ideal specification to ensure that the gas is delivered at the correct flow rate and pressure. The gas panel usually includes a plurality of gas delivery devices (gas sticks), and in a gas delivery device, the components such as manual valve, pneumatic valve, filter, pressure display, pressure regulating valve, tee, etc. in front of the mass flow control meter (MFC) usually need to occupy 7 to 8 bases, and the length is about 28.5 x 7 to 39 x 8, i.e. 200 mm-320 mm, and the length of the mass flow meter is about 90-110 mm. Figure 2 A structure diagram of a gas panel in the prior art is shown. As Figure 2As shown, the gas panel is provided with 9 gas delivery devices, and is provided with 3 empty positions for three-way valves and the like to be connected transversely, the disc length of the 9 gas delivery devices is about 400-500 mm, and the width is 480-680 mm. The gas panel is difficult to meet the needs of complex mixed gas and / or proportional distribution after mixed gas, and to achieve the needs, up to three MFCs and more three-way valves and four-way valves are required to achieve complex purging, and at this time, the length of the gas cabinet usually needs to be further increased by 300 mm. If smaller MFCs manufactured by micro-electro-mechanical system (MEMS) microvalves are used to replace the current large MFCs, the gas panel (Gas panel or Gas Box) can be greatly reduced; at the same time, the traditional connection mode based on the modular gas system (IGS) and VCR form and the traditional mechanical three-way valve and four-way valve connected by IGS / VCR will become a bottleneck of the gas panel integration (the volume is too large to accommodate more gas paths, the precision is not high, and the mechanical valve has a large dead volume, which produces a large amount of residual gas). Therefore, it is necessary to further develop three-way valves, four-way valves, mixed gas and / or proportional distribution after mixed gas based on MEMS technology, to further reduce the gas panel (Gas panel or Gas Box) and improve the gas control precision of the gas panel (Gas panel or Gas Box). SUMMARY

[0006] To at least partially solve the above problems in the prior art, the present application provides 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 comprises a plurality of first channels, the first ends of the first channels are provided with a first microvalve array, and the second ends of the first channels are connected with the intermediate cavity.

[0008] The second substrate comprises a plurality of second channels, the first ends of the second channels are connected with the intermediate cavity and are provided with a second microvalve array, and the second ends of the second channels are outlets, so that the gas in the intermediate cavity flows out through the second microvalve array and the second channels.

[0009] In an embodiment of the present application, the plurality of first microvalve arrays are configured to control the mass flow of a plurality of reaction gases; and / or

[0010] The plurality of second microvalve arrays are configured to control the mass flow or flux of the mixed reaction gases.

[0011] In an embodiment of the present application, the mass flow control principle is thermal or pressure.

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

[0013] a housing, the housing enclosing the first substrate and the second substrate or being disposed between the first substrate and the second substrate; and / or

[0014] a shut-off valve arranged below the first channel and / or the second channel.

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

[0016] In one embodiment of the present application, the first micro-valve array and the second micro-valve array comprise diaphragm valves or cantilever diaphragm valves.

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

[0018] a control system configured to control the opening and closing of the first micro-valve array and the second micro-valve array.

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

[0020] a gas stirring device arranged in the intermediate cavity, the gas stirring device being configured to accelerate the mixing of the plurality of reaction gases.

[0021] In one embodiment of the present application, the first substrate and / or the second substrate are formed by a plurality of wafer bonds.

[0022] In one embodiment of the present application, the MEMS valve and the smaller volume gas mixing or proportional distribution cavity formed by the MEMS bonding or packaging have a feature size of 5mm-10 microns.

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

[0024] In one embodiment of the present application, a passive mixing unit and / or an active mixing unit are further included, which are arranged inside and / or around the MEMS-based gas control module,

[0025] The passive mixing unit is a wedge-shaped inlet, a Z-shaped channel, a three-dimensional serpentine channel structure, an inlaid structure, a twisted channel, a chemical surface arranged in the channel or the intermediate cavity.

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

[0027] In one embodiment of the present application, the MEMS-based gas control module further comprises a pressure and temperature sensor arranged inside the MEMS-based gas control module.

[0028] In one embodiment of the present application, the pressure and temperature sensor measures at least the pressure upstream of the valve, the pressure and temperature between the substrates, and the pressure downstream of the valve.

[0029] The present application further provides a semiconductor device comprising:

[0030] A plurality of gas inlet lines connected to the plurality of gas control modules;

[0031] The plurality of gas control modules are the MEMS-based gas control modules, wherein the plurality of reaction gases flow into the gas control modules through the gas inlet lines for mixing; and

[0032] A reaction cavity connected to the gas control modules, wherein the mixed reaction gases flow from the gas control modules into the reaction cavity for reaction on the substrates to be processed.

[0033] In one embodiment of the present application, the semiconductor device further comprises:

[0034] A gas inlet module, wherein the plurality of gas inlet lines pass through the gas inlet module to connect to the plurality of gas control modules; and

[0035] A gas outlet module, wherein the purge gas flows from the plurality of gas control modules to the gas outlet module.

[0036] The present application has at least the following advantages: the present application provides a MEMS-based gas control module, a construction method, and a semiconductor device using the same, wherein the structure of the gas panel is optimized by using the MEMS and semiconductor packaging technologies, a smaller gas panel can be obtained, and a larger number of multi-path gas flow partition control of the reaction cavity can be achieved.

[0037] Meanwhile, the precision of the gas control is also improved by 1-12 orders of magnitude due to the use of higher precision MEMS valves and smaller volume mixing or proportional distribution cavities based on MEMS bonding or packaging, whose characteristic size is 5mm-10 microns. In the present application, the "characteristic size" can be understood as "characteristic length". For example, if the three-dimensional structure of a key component of the MEMS-based gas control module is approximately spherical, the characteristic size refers to the radius or diameter of the sphere; or if the three-dimensional structure of a key component of the MEMS-based gas control module is approximately cuboid, the characteristic size refers to the length, width or height of the cuboid. The characteristic size of a key component of a prior art gas panel is 1.125 inch, while the characteristic size of the MEMS-based gas control module is 5mm-10 microns. The unit of the mass flow rate of the gas flow is SCCM or SLM, and a decrease of the characteristic size by 1 order of magnitude means an improvement of the control precision by 3 orders of magnitude, and a MEMS of 100 microns can provide an improvement of the precision by at most 12 orders of magnitude. That is, when the control precision of the prior art is 1 SCCM, the control precision is 1 / 10 3 SCCM. BRIEF DESCRIPTION OF DRAWINGS

[0038] To further clarify the advantages and features of the present application, a more particular description of embodiments of the application will be rendered by reference to specific embodiments thereof which are illustrated in the drawings. It is appreciated that these drawings depict only typical embodiments of the application and are therefore not to be considered limiting of its scope. The drawings show, for the purpose of illustration only, the same or corresponding parts of the application using the same or similar reference numerals and letters.

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

[0040] Figure 2 A schematic diagram of a gas panel in the prior art is shown.

[0041] Figure 3A A functional module diagram of the gas panel is shown.

[0042] Figure 4A A PID diagram of a MEMS-based gas control module in an embodiment of the present application is shown.

[0043] Figure 5A A working state diagram of a MEMS-based gas control module in an embodiment of the present application is shown.

[0044] Figure 6 A PID diagram of a semiconductor device in an embodiment of the present application is shown.

[0045] Figure 7A Fig. 7 shows a schematic view of a three-dimensional structure of a MEMS-based gas control module according to an embodiment of the present application.

[0046] Figure 8 Fig. 8 shows a schematic view of a structure of a semiconductor device according to an embodiment of the present application.

[0047] Figure 9 Fig. 9 shows a schematic view of a cross-section of a mixing unit according to an embodiment of the present application. DETAILED DESCRIPTION

[0048] It should be noted that the components in the various figures could be shown exaggerated in size for illustrative purposes and are not necessarily to scale. In the various figures, identical or similar components are provided with the same reference numerals.

[0049] In the present application, unless specifically indicated otherwise, "arranged on", "arranged above" and "arranged over" do not exclude the presence of an intermediate between the two. Furthermore, "arranged on or above" merely indicates the relative position between two components, which in certain cases, such as after reversing the product direction, can also be converted into "arranged below or under", and vice versa.

[0050] In the present application, the various embodiments merely aim to illustrate the solution of the present application and should not be understood as limiting.

[0051] In the present application, unless specifically indicated otherwise, the quantifier "one", "a" does not exclude the scenario of multiple elements.

[0052] It should also be noted here that, for the sake of clarity and simplicity, only a part of the components or assemblies could be shown in the embodiments of the present application, but a person of ordinary skill in the art could understand that, under the teaching of the present application, the required components or assemblies could be added according to the specific scenario. In addition, unless otherwise stated, the features in different embodiments of the present application could be combined with each other. For example, a feature in the second embodiment could replace the corresponding or functionally similar feature in the first embodiment, and the resulting embodiment also falls within the disclosure or recitation range of the present application.

[0053] It should also be noted here that, within the scope of the present application, the expressions "same", "equal", "equal to" and the like do not mean that the two values are absolutely equal, but allow a certain reasonable error, that is to say, the expressions also cover "substantially the same", "substantially equal", "substantially equal to". By analogy, in the present application, the terms "perpendicular to", "parallel to" and the like also cover the meanings of "substantially perpendicular to", "substantially parallel to".

[0054] In addition, the numbering of the steps of the methods of the present application does not limit the order in which the method steps are performed. Unless otherwise specified, the method steps can be performed in different order.

[0055] The present application is further illustrated by the following specific embodiments with reference to the accompanying drawings.

[0056] In Figure 2 In the conventional semiconductor equipment such as gas panel or gas box, the gas path is usually simple and no multi-path gas mixing is performed. A single gas flows through a stop valve, a pressure regulating valve, an MFC, a stop valve and then directly enters the reaction cavity. If it is an explosive or toxic gas, a tee valve for purging gas is also needed.

[0057] However, in the epitaxial equipment, it is usually required to accurately mix multiple gases. In such a gas path, gas A, B and even C have their own independent MFCs, and the gas with a flow rate of Qa, Qb and / or Qc is injected into the confluence header. The total flow rate of the mixed gas is Qtotal=Qa+Qb+Qc. A gas with a flow rate of Qmix (Qmix

[0058] Further, in order to accurately control the process, the same gas injected into the reaction cavity can be controlled in zones, i.e. the single-path gas is split by the MFC to become multi-path gas injected into the reaction cavity through different injection points. In the case of gas mixing, N proportional control flow meters are arranged below the mixing mass flow meter. At this time, the number of MFCs is N+4 (MFCa b c+MFCmix+n×Proportional MFC), while if independent mixing is performed from N injection points, 4N MFCs (n×(MFCa b c+MFCmix)) are needed. In comparison, the number of MFCs can be reduced by 3N-4.

[0059] The gas panel can usually be divided into multiple layers according to the order of gas inlet, Figure 3A -D shows a functional module diagram of the gas panel, in which CV represents a check valve, MV represents a manual valve, GF represents a gas filter, PV represents a pneumatic valve, RG represents a pressure regulator, GA represents a pressure gauge, and MFC represents a mass flow controller. As shown in the figure, Figure 3AThe first layer includes a pneumatic / manual shut-off valve, a manual pressure reducing valve, a pressure display gauge and / or a filter, and can further include a purge tee or cross valve. The second layer includes an MFCa, an MFCb and an MFCc, which are used to perform a first mass flow measurement. The third layer includes a gas mixing mass flow meter, which is used to perform a gas mixing mass flow measurement. The fourth layer includes a proportional control flow meter or a gas splitter, which is used to perform a multi-way distribution of a single gas. The fifth layer includes a shut-off valve or an atomic layer deposition (ALD) valve. Figure 3B The second layer includes an MFCa, an MFCb and an MFCc, which are used to perform a first mass flow measurement. The third layer includes a gas mixing mass flow meter, which is used to perform a gas mixing mass flow measurement. The fourth layer includes a proportional control flow meter or a gas splitter, which is used to perform a multi-way distribution of a single gas. The fifth layer includes a shut-off valve or an atomic layer deposition (ALD) valve. Figure 3C The second layer includes an MFCa, an MFCb and an MFCc, which are used to perform a first mass flow measurement. The third layer includes a gas mixing mass flow meter, which is used to perform a gas mixing mass flow measurement. The fourth layer includes a proportional control flow meter or a gas splitter, which is used to perform a multi-way distribution of a single gas. The fifth layer includes a shut-off valve or an atomic layer deposition (ALD) valve. Figure 3D The second layer includes an MFCa, an MFCb and an MFCc, which are used to perform a first mass flow measurement. The third layer includes a gas mixing mass flow meter, which is used to perform a gas mixing mass flow measurement. The fourth layer includes a proportional control flow meter or a gas splitter, which is used to perform a multi-way distribution of a single gas. The fifth layer includes a shut-off valve or an atomic layer deposition (ALD) valve.

[0060] In the present application, by wafer-level three-dimensional integration of MEMS temperature sensors, MEMS pressure sensors, MEMS shut-off valves and MEMS proportional control valves, a semiconductor device gas panel with complete functions and ultra-small size can be obtained, so that the traditional VCR joint and metal pipeline or the surface-mounted W-shaped seal or C-shaped seal can be avoided.

[0061] In the present application, all the shut-off valves and proportional control valves are located on a MEMS substrate (the MEMS substrate can be a wafer or a plurality of wafers bonded together), and the proportional control valves and the shut-off valves can be arranged in pairs on two sides of the same substrate. At least two layers of proportional control valves are connected to form a closed space by wafer bonding technology or packaging technology. The space and the valves located on the upper and lower surfaces of the space can realize proportional gas mixing, mass flow control of mixed gas, purging and replacement functions, and / or three-way and four-way functions required for purging and mixing.

[0062] In the space formed by the two layers of substrates, pressure and temperature sensors are provided to obtain the temperature of the device and the pressure upstream and downstream of the valves, so that the device can be controlled according to the standard thermal or pressure mass flow principle. Further, since the pressure MFC does not require a heater and a laminar flow element, the present application is more inclined to use the pressure principle for control, i.e. the flow is proportional to P 上游 > 2P 下游 under the blocked flow condition (P 上游 , and the flow is proportional to the square difference of the upstream and downstream pressures under the unblocked flow condition.

[0063] In the present application, the parameters measured by the sensors include at least the upstream pressure, the pressure and temperature between the substrates and the downstream pressure.

[0064] Figure 4A -C shows the piping and PID (process identification diagram) of a MEMS-based gas control module in an embodiment of the present application. As shown in FIG. 1C, the first layer includes a pneumatic / manual shut-off valve, a manual pressure reducing valve, a pressure display gauge and / or a filter, and can further include a purge tee or cross valve. The second layer includes an MFCa, an MFCb and an MFCc, which are used to perform a first mass flow measurement. The third layer includes a gas mixing mass flow meter, which is used to perform a gas mixing mass flow measurement. The fourth layer includes a proportional control flow meter or a gas splitter, which is used to perform a multi-way distribution of a single gas. The fifth layer includes a shut-off valve or an atomic layer deposition (ALD) valve. Figure 4AAs shown, the device has the function of mixing multiple gases in proportion, and can perform mass flow control and purging replacement of mixed gases. The device includes a first substrate 410, a second substrate 420, and an outer shell 430. The outer shell 430 surrounds the first substrate 410 and the second substrate 420 or is arranged between the first substrate and the second substrate 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 ends of the first channels are provided with a first microvalve array 450, and the second ends of the first channels are connected to the intermediate cavity 440, so that multiple reaction gases flow into the intermediate cavity 440 through the first microvalve array and the first channels for mixing. The second substrate 420 is arranged below the first substrate 410 and includes a plurality of second channels. The first ends of the second channels are connected to the intermediate cavity and are provided with a second microvalve array 460, and the second ends of the second channels are outlets, so that the gases in the intermediate cavity 440 flow out through the second microvalve array 460 and the second channels. As shown in Figure 4B As shown, the device further increases the stop valves 470 and 480. As shown in Figure 4C As shown, the device only provides the stop valve 480 at the second substrate, and the stop valve 470 provided at the first substrate can be cancelled. In the present application, the gas control module can be integrated with the mixed gas and three-way purging valve through the chip-to-chip bonding, high-purity ceramic / metal packaging, and metal sealing gasket. Therefore, the outer shell 430 can be a side wall structure for realizing the sealing bonding of the first substrate and the second substrate. Alternatively, the outer shell 430 can be a separate sealing outer shell to wrap the first substrate and the second substrate therein.

[0065] The working mode of the MEMS-based gas control module shown in Figure 4A As shown in the working mode of the MEMS-based gas control module shown in Figure 5A As shown in the working mode of the MEMS-based gas control module shown in Figure 5A As shown, in the mixed gas mode, the microvalve arrays at the inlets of the gases A and B and the microvalve arrays at the outlets of the cavities, injection ports, or shower heads are opened, and the gases A and B flow from the inlets, mix in the intermediate cavity, and flow to the cavities, injection ports, or shower heads. As shown in Figure 5B-C, the microvalve arrays at the inlet of purge gas and purge gas array at the outlet of the first substrate or the second substrate are opened, the purge gas flows in from the inlet and out from the outlet of the first substrate or the second substrate. Since the mixing process is the superposition of mass flow control and three-way / four-way / multi-way function, the purge process is a simplified mixing process without proportional mixing and only with multi-way, so it can be integrated in the same module. The microvalve arrays in the device can be staggered to improve the efficiency of mixing or purging. The microvalve arrays can be diaphragm valves or cantilever diaphragm valves, which are controlled by the control system based on software driving to control their opening and closing.

[0066] Figure 6 A PID diagram of a semiconductor device in one embodiment of the present application is shown. As shown in Figure 6 which can be standard 3 / 8, 1 / 4 or 1 / 8 pipes, using VCR or IGS devices and connections, down into a plurality of the MEMS-based gas control modules. Due to the presence of the MEMS microvalve array, the flow of the microvalve array depends on the number of microvalves or the area of the microarray, i.e. at least one time the flux of the microvalve array (area) is needed before and after the gas distribution. The gas distribution strategy from 1 to N cannot reduce the number of microvalves, the most simple and effective method is to use N groups of mixing structures, and control them separately. Among them, gas A, B and carrier gas (purge gas) pass through traditional manual stop valve, pneumatic stop valve, filter and pressure regulating valve, respectively enter the mixing space between the first substrate and the second substrate through the gas distribution pipeline. A plurality of first proportional control valves are arranged on the first substrate for mass flow control of the gas before mixing. A plurality of second proportional control valves are arranged on the second substrate for mass flow control or flux control of the mixed gas. A gas stirring disturbance structure can be arranged between the first substrate and the second substrate to help accelerate the mixing. Stop valves can be arranged below the first proportional control valves and / or the second proportional control valves to ensure the cut-off of the gas. Through this structure, all the gas panels and gas tanks on the semiconductor (flat panel, LED, solar energy, etc. generic semiconductor technology) device can be connected through the traditional VCR or IGS structure.

[0067] Devices for promoting gas mixing can also be arranged inside and / or around the MEMS-based gas control module. Mixing techniques are passive and active: in the MEMS structure, passive mixing can meet the needs well due to the larger specific surface area compared to traditional VCR / IGS technology. At the same time, the MEMS processing technology can well realize these passive fluid disturbance structures.

[0068]

[0069] "Active" mixing is another important type of mixing. In active mixing, the mixing efficiency is improved by external forces applied to the sample. To achieve an active mixing scheme, some special transducers need to be added to the present application. To achieve "active" mixing of fluids, different physical means are involved: acoustic waves, pressure disturbances, electromagnetic fields, thermal methods. MEMS actuation technology can effectively provide these required physical fields.

[0070]

[0071]

[0072] "Active" mixing processes involve different physical means: acoustic waves, pressure disturbances, magnetic fields, thermal methods. For example, acoustic waves enhance mixing, while the external energy required for active mixing can cause side effects, such as the heating effect of acoustic waves causing possible decomposition / deposition of the gas / precursor. Therefore, the required active mixing drive method, the amount of energy, needs to be carefully selected according to the gas used. Therefore, when passive methods can meet the mixing requirements, passive methods should be preferred.

[0073] According to the passive mixing techniques and active mixing techniques described above, passive mixing units and active mixing units can be provided inside and / or around the MEMS-based gas control module. The passive mixing units can be wedge-shaped inlets, Z-shaped channels, three-dimensional serpentine channel structures, mosaic structures, twisted channels, chemical surfaces provided in the channels or intermediate cavities. The active mixing units can be acoustic wave generating devices, pressure disturbance applying devices, magnetic field generating devices, electric field generating devices, heaters, etc. provided inside or outside the channels or intermediate cavities.

[0074] Figure 9 A cross-sectional schematic view of a mixing unit according to an embodiment of the present application is shown. As shown in FIG. 6, at the outlet of the second substrate, a spiral or other twisted or elongated flow path structure is provided around the outlet, so that the travel of the gas that has not been sufficiently mixed is lengthened and / or the disturbance is increased. Figure 9

[0075] The mixing unit can be fabricated by etching methods, or fabricated on a third substrate and assembled onto the first or second substrate by bonding or the like.

[0076] Figure 7A FIG. 7 shows a three-dimensional structure schematic of a MEMS-based gas control module according to an embodiment of the present application. In this embodiment, the gas control module is provided with a three-dimensional structure, and the gas control module is provided with a three-dimensional structure. Figure 7A A three-dimensional structure of a gas control module provided with a stop valve on the back of the substrate is shown, and the structure for dispensing three kinds of gas at the top of the gas control module is omitted. Figure 7B ​The three-dimensional structure of the gas control module without a cutoff valve on the back of the substrate is shown, and the partial structure of the top of the gas control module for distributing three kinds of gas can be seen. Figure 7C The perspective view of the top of the gas control module is shown, and the channels where three different gases enter respectively can be seen. Figure 7D The three-dimensional perspective view of the top of the gas control module is shown, and the channels where three different gases enter respectively and the proportional control valve at the first substrate can be seen.

[0077] As shown in Figure 7A The back of the substrate of the gas control module can be provided with a cutoff valve or not. The gases entering the gas control module can be divided into three groups, where three-way gas mixing can be performed, or two-way gas mixing can be performed, and the third valve is used for purging or purge exhaust. The upper or lower valve can be used for purge exhaust, and since the lower exhaust port is usually close to the cavity, it is opposite to the shower head or injector of the reaction cavity, so it is more reasonable to arrange the purge exhaust port upward. Without considering the packaging shell, the area of the substrate in the gas control module can be controlled to 10mm x 10mm, which can realize the functions of the second, third and fourth layers of the traditional gas panel with a flow rate of up to 20-80SLM.

[0078] Figure 8 The structural schematic diagram of a semiconductor device in one embodiment of the present application is shown. As shown in Figure 8 The sealing structure can be provided on each gas control module, which is overlapped with each other, so that multiple reaction gases flow to the first micro-valve array on the first substrate through the top gas distribution disc, and the mixed reaction gases flow to the reaction cavity from the second micro-valve array on the second substrate. Specifically, the head module (gas inlet module) and the tail module (gas outlet module) perform gas inlet and gas outlet respectively, and the middle gas control modules can be overlapped to perform gas inlet and exhaust. The middle gas control modules exhaust downward through the second substrate to form mixed gas output of the injection points of the reaction cavity. In Figure 8 , two middle gas control modules correspond to the nozzles of two injection points, and three groups of reaction gases are mixed in mass flow and then output independently. Further, multiple middle gas control modules can be connected to provide more independent mixed gas injection points, and each gas control module has complete purging function. The width of one gas control module can be 10mm, corresponding to a 12-inch semiconductor substrate, which can provide more than or equal to 30 independently controlled mass flow mixed gas injection points in a single dimension, and the VCR or IGS pipeline can also be as few as possible, in Figure 8 , reaction gases A, B and C correspond to 3 gas delivery devices respectively.

[0079] In general, in the present application, the first layer of the conventional gas panel can be arranged using conventional technology, including pneumatic / manual shut-off valves, manual pressure reducing valves, pressure display tables, and / or filters, because the number of valves used is small, one tube for each gas in a chamber, and the number of valves does not increase with the complexity of the gas circuit. The purge tee or cross of the first layer of the conventional gas panel can be integrated into the first substrate or other substrate that implements the second layer functionality. The first substrate can implement the functionality of the first mass flow metering of the second layer of the conventional gas panel. The first substrate or the second substrate can implement the functionality of the mixed gas mass flow metering of the third layer of the conventional gas panel. The third substrate, or through the first substrate and the second substrate, can implement the functionality of the proportional control valve of the conventional gas panel for multi-path distribution of a single-path gas, which, through the first substrate and the second substrate, can reduce the number of layers of modules and the complexity of the topology. The fourth substrate can implement the functionality of the shut-off valve or ALD valve of the conventional gas panel.

[0080] In the present application, the gas control module can be integrated with the mixed gas and tee purge valve through chip-to-chip bonding, high-purity ceramic / metal packaging, and metal sealing gaskets, and can be attached with a shut-off valve to prevent leakage. The upper and lower groups of micro-valve arrays and the space between the micro-arrays form a multi-path valve, a mixed gas, and a proportional gas distribution structure, which implements the functions of the original gas panel, greatly reducing the volume and manufacturing cost of the gas panel.

[0081] The present application only retains the VCR or IGS tube of the first layer of the conventional gas panel, and the purge function of the first layer and the functions of the second, third, and fourth layers of the conventional gas panel can be implemented by the gas control module, greatly reducing the volume, weight, and cost of the gas panel. Most of the reaction chambers use less than 10 kinds of gas, while advanced processes require more than 10 injection ports, and the complexity of the combination will cause the number of various valves to increase. The number of conventional IGS or VCR type valves required by the present application is proportional to the number of reaction gases. The upper and lower groups of micro-valve arrays and the space between the micro-arrays form a multi-path valve, a mixed gas, and a proportional gas distribution structure, which implements the functions of the first layer, the second layer, the third layer, and the fourth layer of the conventional gas panel, greatly reducing the use of pressure reducing valves, manual valves, and pneumatic valves.

[0082] Meanwhile, due to the use of higher precision MEMS valves and smaller volume mixing or proportioning chambers based on MEMS bonding or packaging, the characteristic dimension of which is 5mm-10 microns, the gas control precision is also improved by 1-12 orders of magnitude. In the present application, the "characteristic dimension" can be understood as "characteristic length". For example, if the three-dimensional structure of the key components of the MEMS-based gas control module is approximately spherical, the characteristic dimension refers to the radius or diameter of the sphere; or if the three-dimensional structure of the key components of the MEMS-based gas control module is approximately cuboid, the characteristic dimension refers to the length, width or height of the cuboid. The characteristic dimension of the key components of the prior art gas panel is 1.125 inch, while the characteristic dimension of the MEMS-based gas control module is 5mm-10 microns. The unit of gas flow mass flow is SCCM or SLM, and a decrease in the characteristic dimension by 1 order of magnitude means an improvement in control precision by 3 orders of magnitude, and a MEMS of 100 micron level can provide an accuracy improvement of up to 12 orders of magnitude. That is, when the control precision of the prior art is 1 SCCM, the characteristic dimension decreases by 1 order of magnitude, and the control precision is 1 / 10 3 SCCM.

[0083] Although various embodiments of the present application have been described above, it should be understood that they have been presented by way of example only, and not limitation. It will be apparent to persons skilled in the relevant art that various modifications, combinations and changes can be made to the embodiments without departing from the spirit and scope of the present application. Therefore, the breadth and scope of the present application disclosed herein should not be limited by the above disclosed exemplary embodiments, but should only be defined in accordance with the appended claims and their equivalent replacements.

Claims

1. A MEMS-based gas control module, characterized by, Comprising: a first substrate and a second substrate, wherein an intermediate cavity is formed between the first substrate and the second substrate; an outer shell, which encloses the first substrate and the second substrate or is arranged between the first substrate and the second substrate, the first substrate comprises a plurality of first channels, each of the first channels is provided with a first microvalve at a first end, and a plurality of the first microvalves form a first microvalve array, a second end of the first channel is connected to the intermediate cavity, the second substrate comprises a plurality of second channels, each of the second channels is connected to the intermediate cavity at a first end and provided with a second microvalve, a plurality of the second microvalves form a second microvalve array, and a second end of the second channel is an outlet, so that the gas in the intermediate cavity flows out through the second microvalve array and the second channel, wherein in the mixing mode, the microvalve arrays at the inlets of the first gas and the second gas and the microvalve arrays at the outlets leading to the cavity, the injection inlet or the shower head are opened, the first gas and the second gas flow in from the inlets, mix in the intermediate cavity and flow to the cavity, the injection inlet or the shower head, in the purge mode, the microvalve arrays at the inlets of the purge gas and the purge gas outlets of the first substrate or the second substrate are opened, the purge gas flows in from the inlets and flows out from the outlets of the first substrate or the second substrate.

2. The MEMS-based gas control module of claim 1, wherein, a plurality of the first microvalve arrays are configured to control the mass flow of a plurality of reaction gases; and / or a plurality of the second microvalve arrays are configured to control the mass flow or flux of the mixed reaction gases.

3. The MEMS-based gas control module of claim 2, wherein, The mass flow control principle is thermal or pressure.

4. The MEMS-based gas control module of claim 1, wherein, Further comprising: a stop valve arranged below the first channel and / or the second channel.

5. The MEMS-based gas control module of claim 1, wherein, Wherein the purge gas flows into the gas control module from the first channel, and the purge gas flows out of the gas control module from the first channel or the second channel.

6. The MEMS-based gas control module of claim 1, wherein, The first microvalve array and the second microvalve array comprise diaphragm valves.

7. The MEMS-based gas control module of claim 1, wherein, The first microvalve array and the second microvalve array comprise cantilever diaphragm valves.

8. The MEMS-based gas control module of claim 1, wherein, Further comprising: a control system configured to control the opening and closing of the first microvalve array and the second microvalve array.

9. The MEMS-based gas control module of claim 1, wherein, Further comprising: a gas stirring device arranged in the intermediate cavity, the gas stirring device is configured to accelerate the mixing of a plurality of reaction gases.

10. The MEMS-based gas control module of claim 1, wherein, The first substrate and / or the second substrate are formed by a plurality of wafer bonds.

11. The MEMS-based gas control module of claim 1, wherein, The MEMS valves and the smaller volume mixing or proportioning cavities based on MEMS bonding or packaging have a feature size of 5mm-10 microns.

12. The MEMS-based gas control module of claim 11, wherein, The control accuracy of the MEMS-based gas control module is improved by 1 to 12 orders of magnitude.

13. The MEMS-based gas control module of claim 1, wherein, Further comprising a passive mixing unit and / or an active mixing unit arranged inside and / or around the MEMS-based gas control module, The passive mixing unit is a wedge-shaped inlet, a Z-shaped channel, a three-dimensional serpentine channel structure, an inlaid structure, a chemical surface arranged in the channel or the intermediate cavity; The active mixing unit is a sound wave generating device, a pressure disturbance applying device, a magnetic field generating device, an electric field generating device, a heater arranged inside or outside the channel or the intermediate cavity.

14. The MEMS-based gas control module of claim 1, wherein, Further comprising passive and / or active mixing units disposed inside and / or around the MEMS-based gas control module, the passive mixing units are tortuous channels disposed within the channels or intermediate cavities.

15. The MEMS-based gas control module of claim 1, wherein, Further comprising pressure and temperature sensors disposed inside the MEMS-based gas control module.

16. The MEMS-based gas control module of claim 15, wherein, The parameters measured by the pressure and temperature sensors include at least the pressure upstream of the valve, the pressure and temperature between the substrates, and the pressure downstream of the valve.

17. A semiconductor device, characterized by comprising: Further comprising: a plurality of gas inlets connected to the plurality of gas control modules; a plurality of gas control modules as claimed in any one of claims 1 to 14, wherein the plurality of reactive gases flow into the gas control modules through the gas inlets for mixing; and a reaction chamber connected to the gas control modules, wherein the mixed reactive gases flow from the gas control modules into the reaction chamber for reacting on the substrates to be processed.

18. The semiconductor device of claim 17, wherein, Further comprising: a gas inlet module, wherein the plurality of gas inlets pass through the gas inlet module to connect to the plurality of gas control modules; and a gas outlet module, wherein the purge gas flows from the plurality of gas control modules to the gas outlet module. ​

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