A multi-path proportional air distribution device

Abstract

The application belongs to the technical field of semiconductor equipment, and provides a multi-path proportional gas distribution device, which comprises: a gas inlet device configured to deliver reaction gas to a throttle hole; a plurality of throttle holes, a first side of which is connected with the gas inlet device, and a second side of which is connected with a reaction cavity, wherein the throttle holes are configured to adjust the opening area to adjust the mass flow of the reaction gas passing through the throttle holes; and the reaction cavity, wherein the reaction gas enters the reaction cavity through the throttle holes to perform a reaction. The device can realize true proportional flow control, greatly improve the reproducibility and repeatability of process adjustment, and does not need to control the back pressure upstream of the nozzle, removes the back pressure constraint of multiple MFCs, and avoids the generation of over-constraint. i Natural formation, avoiding the generation of over-constraint.

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 multi-path proportional gas distribution apparatus. BACKGROUND

[0002] In semiconductor equipment, it is a common requirement to perform multi-path proportional gas distribution, which means to distribute the total mass flow to multiple outlets according to specified proportions. Figure 1 、 Figure 2 、 Figure 3 A schematic diagram of a semiconductor equipment with multi-path proportional gas distribution in the prior art is shown.

[0003] As shown in Figure 1 , US patent “US20060216417A1” discloses a system for control of gas injectors, which includes injectors, an inlet and multiple manual metering valves, wherein the inlet controlled by a mass flow controller (MFC) gives the total flow, and the distribution is performed by the manual metering valves. However, this system requires manual adjustment based on experience, and cannot be quantitatively automatically adjusted. Parameters determined on one equipment with a large amount of cost (substrate, reaction gas, equipment man-hour) cannot be directly implemented on other equipment, and a large amount of time and cost is required to re-adjust. In addition, although this system can control the opening degree by means of a motor driving the manual metering valve, the motor can only record the position of the opening degree (0.1 to 4.9 indication range is set for the manual metering valve in this system), and it is difficult to achieve true mass flow control, and the process effect is poor.

[0004] As shown in Figure 2 , US patent “US20180135179A1” discloses a gas injector and vertical heat treatment apparatus, wherein mass flow distribution compensation is performed by setting a gas distribution pipeline with openings and bends, so that multiple horizontally placed substrates can obtain the same flow. However, this equipment has the problem of small implementation flexibility, and a large number of gas distribution pipelines with different shapes and opening sizes need to be prepared in advance for debugging. When the process conditions change, new gas distribution pipelines need to be constructed. And due to the excessive combination of shapes of the gas distribution pipelines, the trial and error situation is complex.

[0005] Furthermore, a common technical solution for multi-path proportional gas distribution in the prior art is to connect multiple MFCs in series and parallel, wherein the total flow is controlled by one MFC, or multiple gases are mixed by multiple MFCs and then the total flow is controlled, and multiple parallel MFCs are arranged downstream of the one or more MFCs upstream of the total flow control, and each downstream MFC controls the flow of a single gas outlet, thereby realizing multi-path proportional gas distribution. However, this solution has the following problems:

[0006] First, the flow outputs of the upstream and downstream MFCs are not strictly equal, and when the gas output of the downstream MFC is not equal to that of the upstream MFC, the middle section of the system will cause pressure instability due to flow imbalance. To solve this problem, as shown in Figure 3 US20170271184A1 discloses a gas flow ratio control method and assembly, wherein one of the multiple downstream MFCs is replaced by a back pressure valve BPC, and when the total flow of the multiple upstream MFCs 126 is not equal to the flow of the multiple downstream MFCs 112, the flow is compensated by the back pressure valve 114.

[0007] In addition, the existing MFC is usually a mass flow controller based on pressure control. Under a certain downstream pressure, multiple downstream MFCs need to adjust the pressure control valve inside the MFC to different pressures. Since the pressure at the outlet of the device is usually limited by the process conditions of the reaction chamber and needs to be controlled by the pressure controller of the reaction chamber rather than the MFC, only the pressure of the upstream MFC can be adjusted. However, since the upstream MFCs are connected to each other, the adjustment of the upstream pressure will cause the pressure of each upstream MFC to not meet the output of the control algorithm. When the flow difference between the MFCs is large, the pressure difference between the large-flow MFC and the small-flow MFC will cause insufficient flow at the large-flow MFC. As shown in Figure 3 Replacing one of the multiple downstream MFCs with a BPC still cannot solve this problem, and using more BFCs will have the problem that the specific flow of multiple BFCs cannot be controlled. SUMMARY

[0008] Applicant found that the cause of the technical problems in the prior art technical solutions using MFC series and parallel multi-path proportional gas distribution lies in that each MFC is a single input output system (SISO), and the proportional mass flow control system is a multiple input multiple output system (MIMO), and the parallel connection of multiple MFCs (SISO) is a simplification that damages the proportional mass flow control system (MIMO), resulting in over-constraint problems. Figure 3 As shown in FIG. 1, the parallel connection of multiple MFCs (SISO) causes over-constraint of back pressure, and a back pressure valve BFC needs to be used to reduce the constraint condition.

[0009] To at least partially solve the above problems in the prior art, the present application provides a multi-path proportional gas distribution device, comprising:

[0010] an inlet device configured to deliver reaction gas to the throttle hole;

[0011] a plurality of throttle holes, a first side of which is connected to the inlet device, and a second side of which is connected to the reaction cavity, wherein the throttle holes are configured to adjust the opening area to adjust the mass flow of the reaction gas passing through the throttle holes; and

[0012] a reaction cavity, wherein the reaction gas enters the reaction cavity through the throttle holes to perform a reaction.

[0013] In an embodiment of the present application, the multi-path proportional gas distribution device further comprises:

[0014] a control unit configured to control the multi-path proportional gas distribution device, wherein the opening area of the plurality of throttle holes is controlled by an electrical signal.

[0015] In an embodiment of the present application, the multi-path proportional gas distribution device further comprises:

[0016] a first pressure sensor configured to measure the pressure on the first side of the throttle hole;

[0017] a second pressure sensor configured to measure the pressure on the second side of the throttle hole; and

[0018] a temperature sensor configured to measure the temperature at the throttle hole.

[0019] In an embodiment of the present application, for choked flow, the control unit is configured to determine the flow Q through the i-th throttle hole according to the following formula: i

[0020] Q i = C × P UPi ,

[0021] wherein C represents a first correlation coefficient, P​UPi P1(i) represents the pressure on the first side of the i-th orifice, wherein the first correlation coefficient C is a constant and A1(i) represents the opening area of the i-th orifice i positive correlation; and / or

[0022] For non-choked flow, the control unit is configured to determine the flow rate Q through the i-th orifice according to the following formula i :

[0023]

[0024] wherein C' represents a second correlation coefficient, A i represents the opening area of the i-th orifice, P DOWNi represents the pressure on the second side of the i-th orifice, R represents the universal gas constant, T represents the temperature, M represents the molecular mass, and γ represents the ratio of specific heat capacities. The second correlation coefficient C' is a constant, and the ratio of specific heat capacities γ = C P / C V represents the specific heat at constant pressure C P and the specific heat at constant pressure C V . In one embodiment of the present application, the multi-path proportional gas distribution device further comprises:

[0025] a pressure distribution vessel arranged between the gas inlet device and the orifices, the pressure distribution vessel being configured such that the pressure at the first side of the plurality of orifices is close to

[0026] wherein a vessel pressure gauge is provided in the pressure distribution vessel, the vessel pressure gauge being configured to measure the pressure P PDV at the inlet of the pressure distribution vessel to determine the pressure drop ΔP i = P UPi - P PDV ; or

[0027] the pressure distribution vessel is configured to determine the pressure P PDV at the inlet of the pressure distribution vessel by measuring the pressure at the first side of the orifice closest to the inlet of the pressure distribution vessel

[0028] In one embodiment of the present application, the gas inlet device comprises a plurality of mass flow controllers configured to provide a plurality of reactant gases with different mass flow rates and to mix them.

[0029] In one embodiment of the present application, the pressure distribution vessel comprises:

[0030] a mass flow meter arranged at an inlet of the pressure distribution vessel, the mass flow meter configured to measure a total flow rate of the reaction gas flowing into the pressure distribution vessel.

[0031] In one embodiment of the present application, the pressure distribution vessel is a gas pipe; or

[0032] the pressure distribution vessel is a preset pipe in the gas inlet device.

[0033] In one embodiment of the present application, the pressure distribution vessel comprises:

[0034] a pressure regulating valve arranged at an inlet of the pressure distribution vessel, the pressure regulating valve configured to set a pressure P PDV of the pressure distribution vessel.

[0035] In one embodiment of the present application, the first pressure sensor is arranged at a first side of each orifice to measure a pressure at the first side of each orifice; and / or

[0036] the second pressure sensor is arranged at a second side of each orifice to measure a pressure at the second side of each orifice.

[0037] In one embodiment of the present application, the orifice comprises a laminar flow element.

[0038] In one embodiment of the present application, when the gas flow through each orifice is choked flow, or when the volume of the reaction chamber is large and the pressure gradient downstream of each orifice is small, the second pressure sensors are combined to measure the pressure at the second side of the orifice, or the measured value P chamber of the chamber pressure gauge PT chamber is used as the pressure at the second side of the orifice.

[0039] In one embodiment of the present application, the multi-path proportional gas distribution device further comprises:

[0040] a gas extraction device connected to the reaction chamber; and

[0041] a pressure control valve arranged between the reaction chamber and the gas extraction device, wherein the pressure of the reaction chamber is adjusted by adjusting the pressure control valve.

[0042] In one embodiment of the present application, the plurality of orifices are configured to be controlled individually, and the plurality of orifices are connected to the gas inlet device and / or the reaction chamber through pipes.

[0043] In one embodiment of the present application, the plurality of orifices are arranged inside the gas inlet device, wherein the gas inlet device comprises:

[0044] a plurality of nozzles, wherein each nozzle is internally provided with a throttle hole and a first pressure sensor.

[0045] In one embodiment of the present application, the pressure distribution container is connected to the throttle hole and the first pressure sensor inside the nozzle through a pipe or a VCR joint; or

[0046] The pressure distribution container is a pipe inside the air inlet device, and the container pressure sensor is arranged inside the air inlet device.

[0047] In one embodiment of the present application, a plurality of parallel throttle holes have a common upstream and downstream, and even share a temperature sensor (integrated in the same housing) and / or share an upstream or downstream pressure sensor, thereby forming a mass flow meter to realize flow expansion of a single throttle hole.

[0048] For the throttle hole or the laminar element with adjustable opening area, it is a relatively large difficulty to control the flux. For some specific structure of the actuator (such as piezoelectric actuator, micro-electromechanical actuator, etc.), the variable physical distance of the execution stroke or movement section is very short, so the flux corresponding to the 100% opening of the throttle hole is very small. By connecting a plurality of throttle holes in parallel, the upstream and downstream of the throttle holes can be common, and a temperature sensor (integrated in the same housing) can be shared, and the upstream and / or downstream can share a pressure sensor, and the total flow Q total of the plurality of throttle holes i (P UPi , A i , P DOWNi ).

[0049] In this embodiment, the purpose of the device is not to proportionally distribute the total flow, but to form a mass flow meter that expands the maximum flow of the throttle hole limited by the stroke of the actuator and realizes a larger flow Q total max=∑Q i max, and the expanded flow Q total max can be accurately controlled in full range.

[0050] The present application has at least the following beneficial effects: the present application proposes a multi-path proportional gas distribution device, which can realize true proportional flow control compared with the device for gas distribution through a manual metering valve, greatly improving the reproducibility and repeatability of the adjustment process. Compared with the device for gas distribution through a plurality of MFCs, the device does not need to control the back pressure upstream of the nozzle, and removes the back pressure constraint of the plurality of MFCs, and the pressure drop ΔP iThe natural formation avoids the generation of over-constraint. Meanwhile, the device integrates a large number of components corresponding to the traditional MFC in the gas inlet device, so that the number of sensors to be arranged can be greatly reduced, the system is more compact, and the cost of the device is greatly reduced. In addition, compared with the device for gas distribution by multiple MFCs, the length of the pipeline for conveying the reaction gas is greatly reduced, the influence of residual gas in the pipeline is reduced, the response speed and accuracy are improved, and the growth rate and control accuracy of the ALD process are improved. BRIEF DESCRIPTION OF DRAWINGS

[0051] To further clarify the advantages and features of the embodiments 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 same or corresponding elements in the drawings are denoted by the same or similar reference signs.

[0052] Figures 1-3 A structure diagram of a semiconductor device with multi-path proportional gas distribution in the prior art is shown

[0053] Figure 4 A structure diagram of a multi-path proportional gas distribution device with single-path gas inlet in an embodiment of the present application is shown.

[0054] Figure 5 A diagram of a throttle hole in an embodiment of the present application is shown.

[0055] Figure 6 A structure diagram of a multi-path proportional gas distribution device with multi-path gas inlet in an embodiment of the present application is shown.

[0056] Figure 7 A structure diagram of a multi-path proportional gas distribution device with independent control in an embodiment of the present application is shown.

[0057] Figure 8A A structure diagram of a vertical furnace tube in an embodiment of the present application is shown.

[0058] Figure 9 A diagram of a gas flow path in a vertical furnace tube is shown.

[0059] Figure 10 A diagram of a vertical furnace tube based on a multi-path proportional gas distribution device with independent control in an embodiment of the present application is shown.

[0060] Figure 11 A structure diagram of a multi-path proportional gas distribution device integrated with a gas inlet device in an embodiment of the present application is shown.

[0061] Figure 12 Fig. 1 shows a schematic view of a reaction chamber with a multi-way proportional gas distribution device integrated with an air intake device in an embodiment of the present application.

[0062] Figure 13 Fig. 2 shows a schematic view of a restriction in an embodiment of the present application.

[0063] Figure 14 Fig. 3 shows a schematic view of the pressure and flow rate variation of a choked flow in an embodiment of the present application.

[0064] Figure 15A Fig. 4 shows a schematic view of a laminar flow element arranged in a pipe in an embodiment of the present application.

[0065] Figure 16A Fig. 5 shows a schematic view of the structure of a laminar flow element in an embodiment of the present application.

[0066] Figure 16B Fig. 6 shows a schematic view of the structure of an outer cylinder member in an embodiment of the present application.

[0067] Figure 16C Fig. 7 shows a top view of an outer cylinder member in an embodiment of the present application.

[0068] Figure 16D Fig. 8 shows a schematic view of the structure of an inner cone member in an embodiment of the present application.

[0069] Figure 17 Fig. 9 shows a schematic view of the gas flow through a laminar flow element in an embodiment of the present application. DETAILED DESCRIPTION

[0070] It should be noted that the components in the various figures can 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 identical reference numerals.

[0071] In the present application, unless specifically indicated otherwise, "arranged on", "arranged above" and "arranged over" do not exclude the presence of an intermediate object between the two. Furthermore, "arranged on or above" merely indicates the relative position between the two components, which in certain cases, such as after reversing the product direction, can also be converted to "arranged below or under", and vice versa.

[0072] In the present application, the various embodiments are merely intended to illustrate the concept of the present application and should not be understood as limiting.

[0073] In the present application, unless specifically indicated otherwise, the quantifier "one", "a" does not exclude the scenario of multiple elements.

[0074] It should also be noted that, in the embodiments of the present application, only a part of components or assemblies can be shown for the sake of clarity and simplicity, but those skilled in the art can understand that, under the teaching of the present application, the required components or assemblies can be added according to the specific scene. In addition, the features in different embodiments of the present application can be combined with each other unless otherwise stated. For example, a feature in the second embodiment can replace a 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.

[0075] It should also be noted that, in the scope of the present application, the expressions "same", "equal", "equal to" and the like do not mean that the numerical values of the two are absolutely equal, but allow a certain reasonable error, that is, the expressions also cover "substantially 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".

[0076] In addition, the numbering of the steps of the methods of the present application does not limit the execution order of the method steps. Unless otherwise specified, the method steps can be executed in different orders.

[0077] The present application will be further described below with reference to the specific embodiments and the accompanying drawings.

[0078] Figure 4 The structure of a single-path gas proportioning device in an embodiment of the present application is shown. As shown in the figure, the device can include a pressure distribution container 401, a plurality of throttle holes (4021, 4022...402i...402n), a reaction cavity 403, a control unit 404, a mass flow meter 405 and a vacuum pump 406. Figure 4 The structure of a single-path gas proportioning device in an embodiment of the present application is shown. As shown in the figure, the device can include a pressure distribution container 401, a plurality of throttle holes (4021, 4022...402i...402n), a reaction cavity 403, a control unit 404, a mass flow meter 405 and a vacuum pump 406. Figure 6 The structure of a single-path gas proportioning device in an embodiment of the present application is shown. As shown in the figure, the device can include a pressure distribution container 401, a plurality of throttle holes (4021, 4022...402i...402n), a reaction cavity 403, a control unit 404, a mass flow meter 405 and a vacuum pump 406. Figure 4 Compared with the single-path gas proportioning device in the embodiment of the present application, the device can be provided with a plurality of MFCs upstream to mix a plurality of reaction gases with different mass and flow, to form a total gas which needs to be proportioned, and to be distributed and output at a plurality of ports according to the specified mass proportion downstream. The total gas enters the pressure distribution container 401 through the mass flow meter 405, wherein the mass flow meter 405 is not necessary in the multi-path gas proportioning device.

[0079] The pressure distribution vessel 401 can be a pre-set channel in a pipe tube or an injector, which is configured such that the pressure of each orifice 402i located downstream or at the outlet of the pressure distribution vessel 401 is close, for example, the bending of the pressure distribution vessel 401 can be reduced, the inlet of the pressure distribution vessel 401 is arranged at the center relative to the multiple outlets, and the maximum inner diameter of the vessel is used as much as possible. A pressure regulating valve is arranged at the outlet of the pressure distribution vessel 401, by which the pressure at the inlet of the pressure distribution vessel 401 can be regulated to P PDV . A vessel pressure gauge and a vessel temperature gauge can be arranged in the pressure distribution vessel 401 to measure the temperature in the pressure distribution vessel 401, or the vessel pressure gauge can be omitted, and the pressure P UPi upstream of the orifice 402i closest to the inlet is measured. PDV .

[0080] A plurality of orifices 402i are arranged at the outlet of the pressure distribution vessel 401. Figure 5 A schematic diagram of one orifice in one embodiment of the present application is shown. As Figure 5 shown, the opening area A i of the orifice 402i is adjustable. In addition, in other embodiments of the present application, the orifice can also be replaced by a laminar flow element (LFE),

[0081] When a large pressure drop is generated due to the length or thinness of the pressure distribution vessel 401, or due to the large difference in the opening area between the multiple orifices 402i downstream of the pressure distribution vessel 401, thereby causing poor pressure equalization effect of the pressure distribution vessel 401, an upstream pressure gauge (PT, Pressure Transducer) PT UP1 ...PT UPi ...PT UPn is arranged at the upstream of each orifice 402i to measure the accurate pressure P UP1 ...P UPi ...P UPn ...P DOWN1 ...PT DOWNi ...PT DOWNn is arranged at the downstream of each orifice 402i to measure the accurate pressure P DOWN1 ...P DOWNi ...P DOWNnwherein when the gas flow through each orifice 402i is choked flow, that is, the flow is insensitive to the downstream pressure (P UPi > 2 x P DOWNi ), or the downstream reaction chamber 403 has a large volume, the pressure gradient downstream of each orifice 402i is small, and each P DOWNi is close to each other, the downstream pressure gauge can be combined as P DOWN , or the measured value P chamber of the chamber pressure gauge PT chamber of the reaction chamber 403 can be used as the pressure downstream of each orifice 402i.

[0082] The reaction chamber 403 is provided with a chamber pressure gauge PT chamber to measure the chamber pressure P chammber . A vacuum pump 406 or other exhaust device is provided to exhaust the reaction chamber 403, and a pressure control valve (PCV) can be provided between the reaction chamber 403 and the vacuum pump 406 to allow the reaction chamber 403 to obtain a specified pressure. The components such as PT, MFC, MFM, etc. can be controlled by the control unit 404.

[0083] The present application provides a multi-path proportional gas distribution device, in which the upstream of a plurality of orifices (4021, 4022...402i...402n) is connected to a pressure distribution vessel 401 (PDV). A valve is provided at the inlet of the pressure distribution vessel 401, which can adjust the pressure at the inlet of the pressure distribution vessel 401 to P PDV , and the gas flows from the inlet of the pressure distribution vessel 401 to the i-th orifice 402i to produce a pressure drop ΔP i = P UPi - P PDV , wherein P UPi represents the pressure upstream of the i-th orifice 402i. The flow rate Q i at the i-th orifice 402i is determined by the pressure P UPi upstream of the i-th orifice 402i, the pressure P PDV at the inlet of the pressure distribution vessel 401, the pressure P chamber of the reaction chamber 403, and the opening area A i of the i-th orifice 402i. Based on the relationship between flow rate and pressure difference in fluid mechanics, and according to the demand of multi-path proportional gas distribution, the required opening area A i of each orifice 402i can be calculated.so that the specified flow rate Q is obtained at the i-th throttle hole 402i i .

[0084] Unlike the conventional technical solution of using a pressure regulating valve to control the pressure gradient of the MFC and then controlling the flow rate, the present application controls the flow rate by adjusting the size of the opening area A i of the variable opening orifice. Since the pressure P UPi upstream of each throttle hole 402i does not need to be controlled in the present application, the flow rate is not controlled by adjusting the pressure difference between the pressure P UPi upstream and the pressure P DOWNi downstream of each throttle hole 402i, so it does not affect the pressure drop ΔP i , thus avoiding the over-constraint problem in the prior art.

[0085] The part of the multi-path proportional gas distribution in the device (that is, the pressure distribution container 401 and the plurality of throttle holes (4021, 4022...402i...402n)) can be arranged similarly to a plurality of MFCs, with the plurality of independently controlled throttle holes 402i connected to the reaction cavity through pipes; it can also be integrated with the gas inlet device, that is, the gas inlet device can be provided with n nozzles (Nozzle), each of which is provided with a throttle hole and an upstream pressure gauge, and the pressure distribution container 401 is connected to the throttle hole and the upstream pressure gauge inside the gas inlet device through pipes or VCR joints and the like. Further, the pressure distribution container 401 can also be a pre-set pipe inside the gas inlet device, and the pressure gauge of the pressure distribution container 401 can be located inside the gas inlet device.

[0086] Figure 7 A structural schematic diagram of an independently controlled multi-path proportional gas distribution device in an embodiment of the present application is shown, taking three gas outlet pipes as an example, that is, after a total gas inlet with a given mass flow rate is proportionally distributed to three gas outlet pipes according to process requirements. A pressure regulating valve is provided at the pressure distribution container 401 to stabilize the pressure at the inlet of the pressure distribution container 401 to P PDV .

[0087] The volume arrangement of the independently controlled device can be very compact, where the pitch of Semi-specification 1.125-inch surface-mounted devices can be 28 mm, the diameter of 3 / 8-inch pipes can be only 9.525 mm, and the diameter of 1 / 4-inch pipes can be 6.35 mm. The compression lines of the throttle holes 4021-4023 should be arranged as parallel as possible, and the pitch between the compression lines can be 1 xmm (3 / 8 pipe diameter) or 8-10 mm (1 / 4 pipe diameter) to reduce the pressure drop ΔP i , so that PUPi = P PDV .

[0088] Downstream of the pressure distribution vessel 401 are throttle orifices 4021-4023, which can be replaced by variable opening laminar flow elements (LFE). In this device, the pressure P DOWNi downstream of the throttle orifices 4021-4023 can be different, so that individual pressure sensors can be arranged downstream of each throttle orifice. The opening area of the throttle orifices 4021-4023 is adjusted according to the data in the database in order to distribute the flow rate of each gas outlet duct in the ratio set in advance. If a very small flow rate is to be distributed to one of the gas outlet ducts, or if the flow rates distributed to the different gas outlet ducts differ greatly (for example, by an order of magnitude), the pressure P UPi can be measured individually upstream of each throttle orifice 4021-4023 in order to compensate for the error caused by the pressure drop.

[0089] In embodiments of the application, the reaction chamber 403 in the multi-gas proportional distribution device for multi-gas inlet as shown in Figure 6 may be a vertical furnace tube. Figure 8A -B shows a schematic diagram of the structure of a vertical furnace tube in an embodiment of the application. Compared to Figure 6 , Figure 8A The vertical furnace tube in -B has multiple layers of horizontally placed substrates 801 from top to bottom, which can be placed on a substrate holder (which can also be a wafer box or a flower basket). A quartz, graphite or ceramic high-temperature lining can be provided in a quartz tube or a metal cavity (bell jar) to construct the reaction chamber 403 of the vertical furnace tube. The vertical furnace tube is heated by an infrared induction lamp or a resistance heater. The substrate holder can be rotatable, and a pedestal can be arranged on the substrate holder, which can be a coated graphite disc, and multiple substrates can be arranged on each layer of the substrate holder. The number of gas outlets of the pressure distribution vessel 401 is close to the number of layers of substrates 801. Each throttle orifice 402i can correspond to multiple gas outlets, that is, one throttle orifice can control multiple gas outlets to control costs. A plasma source or plasma generator can be provided in the vertical furnace tube, and the vertical furnace tube can be used for thermal catalyst accelerated reaction. The vertical furnace tube can be used for atomic layer deposition (ALD) or chemical vapor deposition (CVD). Multiple pressure distribution vessels 401 can be provided in the device to achieve rapid switching of multiple gas species. Different substrates have different vertical heights, corresponding to multiple openings, corresponding to the fluid at different heights in the laminar flow. Multiple throttle orifices can correspond one-to-one to horizontal exhaust outlets.

[0090] Compared to traditional equipment that uses multiple MFCs for multi-path proportional gas distribution, the throttling orifice or laminar flow element in the furnace tube is closer to the reaction chamber than a traditional MFC. Therefore, there is less residual gas between the throttling orifice and the reaction chamber when switching gases. Figure 9 A schematic diagram of a gas flow path in a vertical furnace tube is shown, where path 901 represents the gas flow path from the throttling orifice to the exhaust port according to the present invention, and path 902 represents the gas flow path in conventional equipment. Figure 9 As shown, compared to traditional equipment, the path of the reactant gas in this invention is much shorter. For a large furnace tube with more than 100 substrates, the additional path the reactant gas travels to the farthest substrate can be more than 1 meter. Assuming that the additional path will add 1 second to the residence time of the reactant gas, the time for the first precursor, the second precursor, and the two purge gases in one ALD cycle will be increased by a total of 4 seconds. In traditional equipment, one ALD cycle takes, for example, 12 seconds. Using this invention, the cycle time can be shortened to 8 seconds, increasing the production capacity by 1 / 3.

[0091] Furthermore, in traditional equipment, when valves are closed, residual gas may remain in the gas distribution pipes up to 1 meter long. This residual gas can affect the gas intake distribution for the next intake and may even decompose. Especially in furnace tubes, high ambient temperatures significantly increase the probability of residual gas decomposition. This invention significantly reduces residual gas residue by minimizing the flow path of the reactant gases. In addition, insufficient purging, inadequate adsorption, or insufficient precursors in the furnace tube will affect film thickness. This invention enables precise gas distribution to each substrate, thus solving the problem of airflow control on substrates in large, multi-substrate ALD furnace tubes.

[0092] In embodiments of the present invention, such as Figure 7 The reaction chamber in the independently controlled multi-path proportional gas distribution equipment shown can be a vertical furnace tube. Figure 10 This diagram illustrates a vertical furnace tube of a multi-path proportional gas distribution device based on independent control, according to one embodiment of the present invention. Compared to... Figure 7 The orifices 4021-4023 are connected to the injector, and each orifice controls two substrates.

[0093] Figure 11 A schematic diagram of a multi-way proportional air distribution device integrated with an intake device is shown in one embodiment of the present invention. Figure 11 As shown, multiple MFCs are installed on the right side of the intake device, which mix different gases and then send them into the intake device. The pressure at the inlet of the intake device can be stabilized to P by a pressure regulating valve or other means.PDV The pressure distribution vessel PDV can be a pipe inside the gas inlet device manufactured by mechanical processing, which connects multiple injection ports together. A pressure sensor is arranged upstream of each injection port to measure the pressure P UPi upstream of each injection port i = P PDV -P UPi A plurality of orifices are arranged downstream of the injection ports through which the reaction gas enters the reaction chamber. In this device, the pressure difference between the downstream of each injection port P DOWNi can be ignored, and the pressure P chamber of the reaction chamber is measured instead of P DOWNi . According to the calibration data in the database, the opening area of the orifice can be adjusted to make each injection port distribute the flow according to the preset proportion.

[0094] Compared with the device for gas distribution by manual metering valve, this device can realize true proportional flow control, greatly improving the repeatability and reproducibility of the adjustment process. Compared with the device for gas distribution by multiple MFCs, this device does not need to control the back pressure upstream of the injection port, removes the back pressure constraint of multiple MFCs, and the pressure drop ΔP i of the pipe is naturally formed, avoiding the generation of over-constraint. At the same time, this device integrates a large number of components corresponding to the traditional MFC in the gas inlet device, which can greatly reduce the number of sensors needed to be arranged, make the system more compact, and greatly reduce the cost of the device. In addition, compared with the device for gas distribution by multiple MFCs, this device greatly reduces the length of the pipe for conveying reaction gas, can reduce the influence of residual gas remaining in the pipe, improves the response speed and accuracy, and is beneficial to improve the growth rate and control accuracy of the ALD process.

[0095] Figure 12 A schematic diagram of a reaction chamber arranged with a multi-path proportional gas distribution device integrated with a gas inlet device in an embodiment of the present application is shown. As Figure 12 shown, the reaction chamber in this device can be a quartz chamber or a metal chamber (such as a bell jar), and a quartz, graphite or ceramic high-temperature lining is arranged inside the quartz chamber or metal chamber. A pedestal 1201 or an electrostatic chuck (E-Chuck) can be arranged in the reaction chamber, and the pedestal 1201 can be rotatable, and a layer of substrates can be horizontally arranged on the pedestal 1201, which can include one or more pieces. A side gas inlet device 1202 (V00 Side Injector) can be arranged on the side of the pedestal 1201 to make the reaction gas flow through the substrates from the horizontal direction. The reaction chamber can be heated by induction, infrared lamp or resistance heater.

[0096] The horizontal gas inlet device can be provided with multiple horizontal gas outlets to make the reaction gas flow through the substrate surface in zones. The side gas inlet device 1202 can be Figure 11 The gas inlet device shown in the figure, where the mass flow ratio control can be achieved through the throttle hole and the pressure distribution container. Upstream of the side gas inlet device 1202, two or more reaction gases can be mixed through multiple MFCs. The reaction chamber is provided with a plasma source or a plasma generator, and a thermal catalyst accelerated reaction can be carried out in the reaction chamber. The reaction chamber can be used for atomic layer deposition (ALD) or chemical vapor deposition (CVD). A vacuum pump or exhaust device can be provided in the reaction chamber, and a pressure control device can be provided. It is easy to understand that the side gas inlet device 1202 can also be Figure 7 The independently controlled multi-path proportional gas distribution device shown in the figure.

[0097] An upper gas inlet device 1203 (V00 Top Injector) can also be arranged above the susceptor 1201. The upper gas inlet device 1203 can be provided with multiple gas outlets for flow ratio control through independent throttle holes, and multiple gas outlets can be provided downstream of each independent throttle hole. The upper gas inlet device 1203 can be used to purge the top of the reaction chamber to control the boundary layer height of the horizontally entering reaction gas, and the upper gas inlet device 1203 can be used for diffuse control.

[0098] In the conventional gas distribution device, the gas distribution long pipe is prone to problems such as dead angle, hysteresis, back and forth rotation, uneven gas outlet, etc., which affects the process. In order to suppress these gas flow phenomena, the prior art usually solves the above problems by changing the shape, flow direction, topology, pipe diameter and opening of the pipe, etc. However, these technical solutions often bring new problems while solving one problem. For example Figure 2 The prior art shown in the figure realizes mass flow distribution compensation by adding a 180-degree gas flow return, but also prolongs the path length of the gas flow, increases the volume and molar mass of the residual gas retained inside the gas inlet device, and causes new problems. Using the present application can realize the consistency of gas distribution from the principle and meet the requirements of no hysteresis, dead angle, etc.

[0099] The multi-path proportional gas distribution method in the present application will be described in detail below.

[0100] In the present application, different calculation methods are used for choked flow and non-choked flow. The choked flow and non-choked flow are introduced below.

[0101] The calculation formula of the sound velocity can be expressed as follows:

[0102]

[0103] where c represents the speed of sound, K s represents the stiffness coefficient, and p represents the density. The stiffness coefficient represents the degree of difficulty of compression of a material, and the higher the stiffness coefficient, the more difficult it is to compress the material. As can be seen from the formula, the speed of sound is proportional to the square root of the stiffness coefficient and inversely proportional to the square root of the density. The smaller the density, the faster the speed of sound.

[0104] For a gas, since the propagation of a sound wave in a gas can be regarded as adiabatic compression, the stiffness coefficient K of the gas can be obtained by differentiating the formula PV γ =C (C represents a constant, and y represents an adiabatic index) with respect to P, since the sound wave can be regarded as small-amplitude and the gas can be regarded as a linear medium. Differentiation gives K = yP, so the stiffness coefficient of the gas depends only on the adiabatic index and the pressure.

[0105] Bringing K = yP into the formula for the speed of sound gives the following formula:

[0106]

[0107] Since the pressure of a gas is proportional to the density at a constant temperature, the two cancel each other out, so the speed of sound is independent of the pressure. In addition to the pressure, only the temperature and the mass of the gas molecules can affect the density. Since the higher the temperature, the smaller the density, the higher the temperature, the faster the speed of sound. Since the smaller the mass of the gas molecules, the smaller the density, so the lighter the gas (for example, hydrogen), the faster the speed of sound.

[0108] Since the speed of sound is independent of the pressure, the formula for the speed of sound can be expressed as follows:

[0109]

[0110] where k represents the Boltzmann coefficient, T represents the temperature, and m represents the mass of the gas molecules. The higher the temperature, the smaller the mass of the gas molecules, and the faster the speed of sound.

[0111] Choking is a phenomenon in which, when the flow velocity at a certain cross section in a pipe reaches the speed of sound, the flow velocity, pressure, and flow rate before the speed of sound cross section do not change regardless of how much the pressure outside the outlet of the pipe is reduced. There are many occasions where choking flow is easily formed, and common examples include start-up choking in a supersonic wind tunnel (see wind tunnel), choking in an aircraft inlet, friction pipe choking, and heating pipe choking.

[0112] Taking the choking in an aircraft inlet as an example, when the Mach number Ma 00 <1 of the flow in front of the inlet is less than 1, the flow velocity in front of the inlet increases, the flow velocity at the throat in the inlet increases, and the flow rate increases. When the Mach number Ma 00When =1, the flow rate will not increase even if the velocity of the airflow in front of the inlet is increased, and only supersonic flow and shock waves appear behind the throat. When the Mach number Ma 00 >1 of the airflow far in front is greater than 1, the supersonic airflow is not disturbed before the inlet and directly flows into the inlet. When the throat area is large enough, all the gas entering can pass through, and the inlet is not blocked. When the throat area is too small, the flow rate that can pass through is less than the flow rate directly entering, the throat is blocked, the gas in front of the throat accumulates, the pressure rises, a detached shock wave is formed in front of the inlet, a part of the excess gas flows out, and a supersonic region and a shock wave appear behind the throat. The blocking in the inlet of the aircraft will greatly increase the resistance of the aircraft and significantly reduce the thrust of the engine.

[0113] Figure 13 A schematic diagram of a throttle hole in an embodiment of the present application is shown. As Figure 13 shown, for compressible fluid, if the pressure P1 of the inlet of the throttle hole remains constant and the pressure P2 at the outlet gradually decreases, the mass flow rate through the throttle hole will gradually increase to a maximum value, and the flow rate will not increase even if P2 is further reduced. This situation is called choked flow. Choked flow usually requires P1≥2P2 (the specific ratio is related to the specific heat capacity of the gas), and the flow rate through the throttle hole is only related to P1 and is proportional to the absolute value of P1.

[0114] Figure 14 A schematic diagram of the change of pressure and flow rate of a choked flow in an embodiment of the present application is shown. The choked point of the fluid is determined by the pressure recovery factor F L of the liquid and the critical pressure difference ratio coefficient X T of the gas without an attached pipe, the liquid is formed due to vapor, and the gas reaches the speed of sound at the contraction neck. The choked critical value of the pressure can be calculated by the following formula:

[0115]

[0116] F F =0.96-0.28(P V / P C ) 1 / 2

[0117] Wherein, F F represents the critical pressure ratio factor of the liquid, P V represents the vapor pressure of the fluid, and P C represents the thermodynamic critical pressure.

[0118] The ratio between the choked critical pressure P choked of the throttle hole and P1 can be represented by the following formula:

[0119]

[0120] where n represents the exponent of isentropic expansion / compression. For an ideal gas in a thermal system, n is the ratio of specific heats: n = C p / C v where C p represents the specific heat at constant pressure, C v represents the specific heat at constant volume. n = 1.135 for most process steam working in the wet region, n = 1.30 for superheated steam, n = 1.4 for air, n = 1.31 for methane, and n = 1.667 for helium.

[0121] For air, the calculation of the critical pressure ratio can be expressed as:

[0122]

[0123] The correspondence between n and the critical pressure ratio for other gases can be 1.1135, 0.577; 1.300, 0.546; 1.400, 0.528; 1.667, 0.487.

[0124] The mass flow rate of the choked flow through the orifice, that is, the minimum pressure equal to the sound velocity flow through the orifice, can be expressed as follows:

[0125]

[0126] where m c represents the mass flow rate of the sound velocity flow (kg / s), A c represents the nozzle area (m 2 ), and p1represents the density of the inlet of the orifice (kg / m 3 ).

[0127] For the case of non-choked flow, the pressure function upstream and downstream of the orifice is The secondary flow rate can be determined according to the following formula: Q = k x Function (P UP , P DOWN ).

[0128] At the orifice of the non-choked flow, the flow rate Specifically, it can be expressed as follows:

[0129]

[0130] According to the above formula, under the condition that P UP and P DOWN are constant, the flow rate Q i at the orifice of the non-choked flow is proportional to the opening area A of the non-choked flow, and the opening area A can be adjusted by an electrical control loop and controlled by a control unit in the present application.

[0131] In non-choked flow, the flow is limited by the sonic velocity at the orifice exit, when the upstream pressure P UP is determined, the flow Q i is proportional to the orifice area A. By configuring multiple orifices 402i, the upstream pressure P UPi of the orifices 402i can be maintained substantially constant, so that the effect of back pressure can be minimized. The upstream of the multiple orifices 402i are interconnected, when the flow (flow rate) is large, and the pipe diameter is small, a pressure difference ΔP UPi (P UPi+1 ) = v 2 fLρ / 2D will occur between the orifices. By adjusting the orifices according to the present application, P UPi can be maintained substantially constant, and the pressure difference between the upstream of the multiple orifices 402i is accepted, the orifice area A i is fine-tuned to achieve precise proportional control, without the need to set a pressure control valve for control. In a pressure flow control device, the opening area of the MFC is fixed, and under the condition of fixed downstream pressure, the flow needs to be controlled by pushing P UPi up. When the flow ratio changes, P UPi increases, and Q i also increases.

[0132] For choked flow, when Q i doubles, P UPi also doubles, and at this time, the flow Q j of other orifices will decrease, and P UPj will also decrease. Since P UPi and P UPj are interconnected, the back pressure will interfere with each other and even contradict each other, resulting in over-constraint. When the flow difference is too large, it is difficult to achieve precise control. The situation of non-choked flow is similar.

[0133] When the gas flow through the orifice 402i is choked flow, the flow Q i through the orifice 402i = C x P UPi , where C represents the first correlation coefficient, which is positively correlated with the opening area A i of the i orifices; when the gas flow through the orifice 402i is non-choked flow, the flow Q through the orifice 402i = C x P total , where C represents the first correlation coefficient, which is positively correlated with the opening area A i of the i orifices; when the gas flow through the orifice 402i is choked flow, the flow Q UPi through the orifice 402i = C x P i , where C represents the first correlation coefficient, which is positively correlated with the opening area A DOWNi of the i orifices; when the gas flow through the orifice 402i is non-choked flow, the flow Q i=P UPi -P PDV And ΔP i Satisfy the following formula:

[0134]

[0135] Where ΔP represents pressure drop (Pa), V represents flow velocity (m / s), f represents friction coefficient, L represents pipe length (m), and ρ represents fluid density (kg / m³). 3 D represents the pipe diameter (m).

[0136] When the multi-proportional gas distribution device is running, the total mass flow rate Q is set via MFM or multiple MFCs. total The pressure P at the inlet of the pressure distribution container 401 is set by the pressure regulating valve at the outlet of the pressure distribution container 401. PDV .

[0137] Close all throttle orifices except for orifice 402i, and perform an opening test on orifice 402i. The opening of orifice 402i is determined based on the metering values ​​of the upstream MFC or MFM at a given P. DOWNi and P under various traffic levels UPi The opening area A of the throttling orifice 402i i The relationship. Repeat the above operation for orifices 4021-402n to determine the Q of all orifices 402i. i Mapping, and determining the relationship between each orifice 402i and P at various flow rates. PDV and ΔP i The relationship is as follows. Furthermore, the opening of multiple orifices can be tested simultaneously. For example, while keeping the total flow rate constant, the opening of one orifice can be increased while the opening of another orifice is decreased for testing. Based on the above steps, an adaptive algorithm can be established, and a database can be constructed.

[0138] Input the given total flow Q total and the flow rate Q distributed by each throttling orifice 402i i Q total =∑Q i The initial opening area A of the throttling orifice 402i is matched using the database. i And its corresponding P UPi P DOWNi , where P UPi The pressure difference between the various orifices should be taken into account as reasonably expected.

[0139] Based on the initial matching set {P UPi A i PDOWNi The set of {P} that runs the device and receives actual feedback. UPi A i P DOWNi}. Generally speaking, P DOWNi Controlled by the downstream reaction chamber 403, the reaction is relatively stable, with deviations mainly occurring at P. UPi Above, the given P could not be established at the throttle orifice 402i. UPi A more reasonable {P} can be matched using neural network algorithms or other adaptive algorithms. UPi A i} makes P UPi -P DOWNi Approaching zero.

[0140] In this invention, the orifice can be replaced with a laminar flow element (LFE). Figure 15A -B shows a schematic diagram of a laminar flow element arranged in a pipe according to an embodiment of the present invention. (See diagram below.) Figure 15A As shown in -B, the laminar flow element can be a concentric ring, equidistantly arranged laminar flow plates, or a honeycomb flow channel, etc., arranged in the pipe. The flow rate Q in the laminar flow element can be calculated by the following formula:

[0141]

[0142] Where ΔP represents the pressure drop across the pipe, D represents the pipe diameter, μ represents the fluid viscosity, L represents the pipe length, and k represents the calculation coefficient.

[0143] The structure of the laminar flow element can be a diaphragm valve or a bellows valve. Figure 16A A schematic diagram of a laminar flow element according to one embodiment of the present invention is shown. Figure 16A As shown, the laminar flow element may include an inner cone component 1601 and an outer cylinder component 1602. Figure 16B A schematic diagram of the structure of an outer cylinder component according to one embodiment of the present invention is shown. Figure 16C A top view of an outer cylinder component according to one embodiment of the present invention is shown. Figure 16D A schematic diagram of an inner cone component according to one embodiment of the present invention is shown. Figure 16AAs shown in FIG. 16, the inner diameter of the outer cylinder component 1602 can be the same as the outer diameter of the inner cone component 1601, and the inner cone component 1601 can be provided with a plurality of first laminar flow sheets, and the inner side of the cylinder wall of the outer cylinder component 1602 can be provided with a plurality of second laminar flow sheets. The inner cone component 1601 can be embedded in the outer cylinder component 1602, and the first laminar flow sheets can be embedded in the second laminar flow sheets. The outer cylinder component 1602 is provided with an opening, and the first laminar flow sheets and the second laminar flow sheets can rectify the flow state of the fluid from turbulent flow to laminar flow. By adjusting the depth of the embedding of the inner cone component 1601 in the outer cylinder component 1602, the opening area of the laminar flow element can be adjusted. When the inner cone component 1601 is completely embedded in the outer cylinder component 1602, the opening area of the laminar flow element is reduced to 0, that is, completely closed. When the outer cylinder component 1602 and the inner cone component 1601 are not provided with laminar flow sheets, it is easy to understand that the device is an embodiment of the throttling hole (V00) with adjustable opening area according to the present application.

[0144] Figure 17 The schematic diagram of the gas flow through the laminar flow element in an embodiment of the present application is shown in FIG. 17. Figure 17 As shown in FIG. 17, the gas flow can flow along the path 1701 from the upstream to the downstream of the laminar flow element. The pressure difference ΔP = P UP -P DOWN downstream of the laminar flow element can be measured by a differential pressure gauge, and at least one absolute pressure gauge is provided to provide a reference for the differential pressure gauge, which is usually the pressure gauge of the reaction chamber or the pressure gauge of the PDV. When the flow rate of a single laminar flow element is small or large, the differential pressure gauge can improve the control accuracy of the laminar flow element with small flow rate.

[0145] Although the above describes the embodiments of the present application, it should be understood that they are only presented as examples and not as limitations. It is obvious to those skilled in the relevant art that various combinations, modifications and changes can be made without departing from the spirit and scope of the present application. Therefore, the width and scope of the present application disclosed herein should not be limited by the above disclosed exemplary embodiments, but should only be defined according to the appended claims and their equivalent replacements.

Claims

1. A multi-channel proportional gas distribution device, characterized in that, include: An intake device, configured to deliver the reaction gas to a throttle orifice; Multiple throttling orifices, with a first side connected to an air intake device and a second side connected to a reaction chamber, wherein the throttling orifices are configured to adjust the opening area to adjust the mass flow rate of the reaction gas passing through the throttling orifices, wherein the first side and the second side of the multiple throttling orifices are common. A reaction chamber in which reaction gases enter through the plurality of throttling orifices to carry out a reaction; A first pressure sensor is configured to measure the pressure on a first side of the orifice; A second pressure sensor is configured to measure the pressure on a second side of the orifice; as well as A control unit, configured to control a multi-channel proportional gas distribution device, wherein the opening area of ​​the plurality of orifices is controlled by an electrical signal. For choked flow, the control unit is configured to determine the flow rate Q through the i-th orifice according to the following formula. i : Q i =C×P UPi , Where C represents the first correlation coefficient, P UPi This represents the pressure on the first side of the i-th orifice, where the first correlation coefficient C is related to the opening area A of the i-th orifice. i Positive correlation; and / or For non-blocking flow, the control unit is configured to determine the flow rate Q through the i-th orifice according to the following formula. i : Where C' represents the second correlation coefficient, A i P represents the opening area of ​​the i-th orifice. DOWNi Let R represent the pressure on the second side of the i-th orifice, T represent the universal gas constant, M represent the molecular mass, and γ represent the specific heat ratio, where the second correlation coefficient C' is a constant.

2. The multi-channel proportional gas distribution device according to claim 1, characterized in that, It also includes a temperature sensor configured to measure the temperature at the orifice.

3. The multi-channel proportional gas distribution device according to claim 1, characterized in that, Also includes: A pressure distribution container is disposed between the intake device and the orifice, the pressure distribution container being configured such that the pressures located on a first side of the plurality of orifices are close; The pressure distribution container is equipped with a container pressure gauge, which is configured to measure the pressure P at the inlet of the pressure distribution container. PDV To determine the pressure drop ΔP from the pressure distribution container to the first side of the i-th orifice. i =P UPi —P PDV ;or The pressure distribution container is configured to determine the pressure P at the inlet of the pressure distribution container by measuring the pressure on the first side of the orifice closest to the inlet of the pressure distribution container. PDV ; 4. The multi-channel proportional gas distribution device according to claim 3, characterized in that, The air intake device includes multiple mass flow controllers configured to provide and mix multiple reaction gases with different mass flow rates.

5. The multi-channel proportional gas distribution device according to claim 4, characterized in that, The pressure distribution container includes: A mass flow meter is disposed at the inlet of the pressure distribution container, and the mass flow meter is configured to measure the total flow rate of the reaction gas flowing into the pressure distribution container.

6. The multi-channel proportional gas distribution device according to claim 3, characterized in that, The pressure distribution container is an air tube; or The pressure distribution container is a pre-set pipe in the air intake device.

7. The multi-channel proportional gas distribution device according to claim 3, characterized in that, The pressure distribution container includes: A pressure regulating valve is disposed at the inlet of the pressure distribution container, the pressure regulating valve being configured to set the pressure P of the pressure distribution container. PDV .

8. The multi-channel proportional gas distribution device according to claim 1, characterized in that, The first pressure sensor is installed on the first side of each throttling orifice to measure the pressure on the first side of each throttling orifice; and / or The second pressure sensor is installed on the first side of each throttling orifice to measure the pressure on the second side of each throttling orifice.

9. The multi-channel proportional gas distribution device according to claim 1, characterized in that, The throttling orifice includes a laminar flow element, or the throttling orifice constitutes a laminar flow element.

10. The multi-channel proportional gas distribution device according to claim 8, characterized in that, When the airflow through each orifice is choked flow, or when the volume of the reaction chamber is large and the pressure gradient downstream of each orifice is small, multiple second pressure sensors are combined to measure the pressure on the second side of the orifice, or a chamber pressure gauge PT of the reaction chamber is used. chamber The measured value P chamber As the pressure on the second side of the throttling orifice.

11. The multi-channel proportional gas distribution device according to claim 10, characterized in that, Also includes: An air extraction device, which is connected to the reaction chamber; as well as A pressure control valve is arranged between the reaction chamber and the evacuation device, wherein the pressure of the reaction chamber is adjusted by regulating the pressure control valve.

12. The multi-channel proportional gas distribution device according to claim 1, characterized in that, The plurality of throttling orifices are configured for individual control, and the plurality of throttling orifices are connected to the intake device and / or reaction chamber via pipes.

13. The multi-channel proportional gas distribution device according to claim 3, characterized in that, The plurality of throttling orifices are arranged inside the intake device, wherein the intake device includes: Multiple nozzles, each of which has a throttling orifice and a first pressure sensor inside.

14. The multi-channel proportional gas distribution device according to claim 13, characterized in that, The pressure distribution container is connected to the throttling orifice inside the nozzle and the first pressure sensor via a pipe or VCR connector; or The pressure distribution container is a pipe inside the air intake device, and the container pressure sensor is arranged inside the air intake device.

15. The multi-channel proportional gas distribution device according to claim 1, characterized in that, The multiple throttling orifices are connected in parallel to form a mass flow meter, and the total flow rate Q of the multiple throttling orifices is... total =∑Q i (P UPi A i ,P DOWNi ).

16. The multi-channel proportional gas distribution device according to claim 15, characterized in that, A temperature sensor shared by the multiple throttling orifices is arranged within the same housing; and / or A common pressure sensor is arranged upstream and / or downstream of the plurality of throttling orifices.

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