Process cavity with controllable gas flow field and plasma processing equipment

Abstract

The invention relates to the technical field of semiconductor manufacturing equipment, in particular to a process cavity with a controllable gas flow field and plasma processing equipment, and the process cavity comprises a cavity body which is provided with a cavity for bearing a wafer; the air inlet channel is communicated with the cavity; the main air exhaust channel is arranged at the bottom of the cavity body and is communicated with the cavity; the main air exhaust channel is connected with a main control valve; the auxiliary air exhaust channel is arranged on the side wall of the cavity body and is communicated with the cavity; the main control valve and the auxiliary control valve work cooperatively. The control device is in communication connection with the main control valve and the auxiliary control valve; through the cooperation of the auxiliary air exhaust channel and the auxiliary control valve and the cooperation of the main air exhaust channel and the main control valve, the flow field distribution in the process cavity is adjusted, the gas concentration gradient and the edge dead zone in the radial direction of the wafer are guided to be eliminated, and the consistency of the side face angle, the surface roughness center area and the edge area of the outer ring groove or hole of the wafer is achieved.

Description

Technical Field

[0001] The present invention relates to the technical field of semiconductor manufacturing equipment, and in particular to a process chamber with controllable gas flow field and plasma processing equipment. Background Art

[0002] Existing inductively coupled plasma (ICP) etching equipment generally uses a "top-center air intake + bottom-center single exhaust" structure, with the exhaust rate adjusted by a bottom swing valve. This solution can only achieve coarse adjustment of the overall pressure and cannot locally fine-tune the radial flow field distribution of the wafer, resulting in: (1) The gas forms a high-concentration central jet during the vertical flow process, resulting in a significantly higher process gas concentration in the center of the wafer than in the edge area; (2) Due to the movement characteristics of gas tending to the low-pressure area, part of the process gas is extracted by the bottom center exhaust port before it comes into contact with the wafer surface, forming a "dead zone" on the outer circle of the wafer; In the existing technology, simply adjusting the pumping rate of the bottom swing valve cannot change the inherent concentration gradient of "high gas concentration in the central area and low gas concentration in the edge area", nor can it eliminate the edge dead zone caused by the fixed flow field route, which will still cause the problem of inconsistent side angles of the outer groove / hole of the wafer and the surface roughness of the central area and the edge area. Summary of the Invention

[0003] To achieve the above objectives, the present invention provides a process chamber with controllable gas flow field, comprising: The cavity body has a cavity for carrying the wafer; an air inlet channel, communicating with the chamber and configured to introduce a process gas into the chamber; A main exhaust channel is provided at the bottom of the chamber body and communicates with the chamber; the main exhaust channel is connected to a main control valve and is used to establish an exhaust flow field of process gas in the axial direction of the wafer; An auxiliary exhaust channel is provided on the side wall of the chamber body and is in communication with the chamber, and the horizontal planes of the exhaust ports of the auxiliary exhaust channel are all located above the wafers carried thereon, and the auxiliary exhaust channel is connected to a corresponding auxiliary control valve for establishing an exhaust flow field of the process gas in the radial direction of the wafer; there are multiple auxiliary exhaust channels, and the exhaust ports of the multiple auxiliary exhaust channels are arranged on the side wall of the chamber body in an annular structure; A control device is communicatively connected with the main control valve and the auxiliary control valve, and is used to control the main control valve and the auxiliary control valve to work in coordination so as to adjust the flow field distribution in the process chamber.

[0004] Optionally, there are multiple auxiliary air pumping channels, and the air pumping ports of the multiple auxiliary air pumping channels are arranged at the same height of the side wall of the cavity body to form a single-layer annular structure for establishing a single-layer radial air pumping flow field in the cavity body.

[0005] Optionally, there are multiple auxiliary exhaust channels, and the multiple auxiliary exhaust channels are arranged at at least two different heights on the side wall of the cavity body to form at least two layers of annular structures; each layer of the annular structure includes at least multiple auxiliary exhaust channels, which are used to form at least two layers of radial exhaust flow fields in the axial direction of the wafer.

[0006] Optionally, the number of the auxiliary air pumping channels included in each layer of the annular structure is the same, so as to form at least two identical radial air pumping flow fields.

[0007] Optionally, the number of the auxiliary exhaust channels included in two adjacent layers of the annular structure increases layer by layer from top to bottom along the axial direction of the wafer to form two different radial exhaust flow fields.

[0008] Optionally, the distance between the lower edge of the exhaust port and the upper surface of the wafer in the axial direction of the wafer is between 5 mm and 40 mm.

[0009] Optionally, the auxiliary air pumping channel is an independent channel structure, and the channel cavity height of the channel structure is between 1.5 mm and 4 mm.

[0010] Optionally, the auxiliary air pumping channel is an independent channel structure and has an L-shaped structure. The auxiliary air pumping channel includes a transverse section and a vertical section, and the transverse section is used to connect the inner cavity of the cavity body and the vertical section; Among them, the channel cavity height of the horizontal section is between 1.5mm and 4mm; the lower end opening of the vertical section is arranged on the bottom wall of the cavity body and is connected to the auxiliary control valve, and the channel cavity height of the vertical section is between 40mm and 80mm.

[0011] Optionally, the auxiliary air pumping channel is a composite channel structure, which includes a first channel section, a second channel section and a third channel section that are connected in sequence, the channel cavity of the second channel section is an annular structure, the first channel section is used for connecting the second channel section with the inner cavity of the cavity body, and there are several first channel sections, and several second channel sections are arranged in an equidistant annular pattern along the wall of the cavity body; the third channel section is used for connecting the second channel section with the auxiliary control valve, and there are M third channel sections, where M is a positive integer greater than or equal to 1, wherein the first channel section is connected to the inner annular wall of the annular structure, and the third channel section is connected to the lower end face of the second channel section.

[0012] Optionally, an extension line of a central axis of the exhaust port of the auxiliary exhaust channel is arranged perpendicular to the axial direction of the wafer.

[0013] Optionally, the extension line of the central axis of the exhaust port of the auxiliary exhaust channel is tilted to the axial direction of the wafer to form an angle, the size of the angle is between 20° and 60°, and the exhaust port is tilted upward.

[0014] Optionally, the main control valve is a swing valve.

[0015] Optionally, the auxiliary control valve is a butterfly valve.

[0016] Optionally, the main air pumping channel and the auxiliary air pumping channel share a vacuum pump.

[0017] Optionally, the main air pumping channel and the auxiliary air pumping channel are respectively connected to different vacuum pumps.

[0018] To achieve the above-mentioned purpose, the present invention further provides a plasma processing device, comprising the process chamber with controllable gas flow field and a carrier platform, wherein the carrier platform is used to carry wafers.

[0019] The beneficial effects of the present invention are as follows: The present invention adjusts the flow field distribution in the process chamber through the coordination of the auxiliary exhaust channel and the auxiliary control valve with the main exhaust channel and the main control valve, guides and eliminates the gas concentration gradient and the edge dead zone in the radial direction of the wafer, and achieves the consistency of the side angle of the outer ring groove or hole of the wafer and the surface roughness of the central area and the edge area. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 This is a gas flow field distribution diagram when not adjusted in the present invention; Figure 2 This is the gas flow field distribution diagram after adjustment in the present invention; Figure 3 For the present invention Figure 1 Middle top view cross-sectional structural diagram; Figure 4 This is a schematic structural diagram of the present invention for forming at least two ring structures; Figure 5 Schematic diagram of the auxiliary air pumping channel structure in an L-shaped structure in the present invention; Figure 6 A schematic diagram of a structure in which a plurality of transverse sections are provided in the auxiliary air pumping channel with an L-shaped structure in the present invention; Figure 7 Schematic diagram of the structure of the auxiliary air pumping channel of the present invention as a composite channel structure; Figure 8 This is a schematic diagram of the structure in which the air extraction port is tilted in the present invention.

[0021] Description of Reference Numerals 1. Cavity body; 2. Wafer; 3. Air inlet channel; 4. Main exhaust channel; 5. Auxiliary exhaust channel; 51. Horizontal section; 52. Vertical section; 53. First channel section; 54. Second channel section; 55. Third channel section. DETAILED DESCRIPTION

[0022] In order to make the purpose, technical solutions and advantages of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention. Unless otherwise defined, the technical terms or scientific terms used herein should be the common meanings understood by people with ordinary skills in the field to which the present invention belongs. The words "including" and similar words used in this article mean that the elements or objects appearing before the word cover the elements or objects listed after the word and their equivalents, without excluding other elements or objects.

[0023] Existing ICP etching equipment generally adopts the structure of "top center air intake + bottom center single exhaust". This structure forms a vertical downward flow field during the wafer processing process. Since the air inlet is located at the top center of the chamber, the process gas is ejected vertically along the shortest path toward the center of the wafer under the combined action of gravity and axial exhaust negative pressure, forming a high-speed central jet; while the edge area is far away from the exhaust port and is blocked by the detour of the top jet, the air flow speed drops sharply and the renewal is slow, causing gas to stagnate and be "preemptively taken away" by the central jet. As a result, the center concentration is high and the edge concentration is low, and a radial concentration gradient is generated. Figure 1 As shown in the flow field in the figure, the process gas concentration in the center area of ​​the wafer is high, and the process gas flow concentration in the edge area is low, forming a significant radial concentration gradient and an edge dead zone, which in turn causes inconsistencies in the etching depth, sidewall angle, and wafer surface roughness between the center and edge of the wafer, resulting in a reduced yield. At the same time, the traditional adjustment method can only roughly adjust the overall pressure through the bottom main exhaust channel 4 and the swing valve, and cannot finely control the local flow field.

[0024] In response to the problems existing in the prior art, an embodiment of the present invention provides a process chamber with a controllable gas flow field, wherein a plurality of auxiliary exhaust channels 5 are arranged on the side wall of the chamber body 1, and the plurality of auxiliary exhaust channels 5 are arranged in an equidistant ring shape, specifically, in an equidistant ring shape around the vertical center line of the chamber body 1; the advantage of such an arrangement is that it can pressure-guide the convection of the process gas in the radial direction of the wafer 2, thereby changing the flow field of the process gas through coordination with the main exhaust channel 4 and the main control valve (swing valve), balancing the gas concentration in the central area and the edge area of ​​the wafer 2, so that the gas concentration in the central area and the edge area remain consistent.

[0025] Specifically, if Figure 1 and Figure 2 As shown, the process chamber with controllable gas flow field includes a chamber body 1, which has a chamber for carrying a wafer 2. The chamber body 1 adopts a universal cylindrical structure. In the etching process, the chamber body 1 is not only the physical boundary of the process gas, but also the core component that determines the uniformity of the gas flow field of the plasma distribution and the consistency of the etching results. It is also used to carry the wafer 2. In the prior art, the wafer 2 is placed horizontally in the chamber body 1.

[0026] An air inlet channel 3 is provided at the top of the chamber body 1. The air inlet channel 3 is connected to the chamber and is used to introduce process gas into the chamber body 1. The air inlet channel 3 is preferably provided in the middle of the top of the chamber body 1. The air inlet channel 3 can be a pipe, a through hole, or a shower head structure, but is not limited to pipes, through holes, or shower heads.

[0027] The bottom of the cavity body 1 is provided with a main air extraction channel 4, which is connected to the cavity. Figure 1 and Figure 2 As shown, main exhaust channel 4 can be a through hole or a pipe, but is not limited to these two types. It is preferably a through hole. Main exhaust channel 4 is connected to a main control valve (not shown). The cooperation between main exhaust channel 4 and the main control valve regulates and isolates the gas flow and pressure within the chamber of the wafer 2 etching vacuum system. Main exhaust channel 4 is connected to an external vacuum pump, and the main control valve is located in the gas flow channel to adjust the opening of main exhaust channel 4.

[0028] The main control valve may be a butterfly valve, but is not limited to a butterfly valve.

[0029] To reduce costs, the butterfly valve in this application adopts an existing structure. Specifically, the butterfly valve includes a disc-shaped valve disc (disc) fixed to a valve stem, and the valve body is a short cylindrical shape. A simple 90° rotation of the valve stem allows the disc to be parallel (fully open) or perpendicular (fully closed) to the main exhaust channel 4, and the flow rate can be linearly adjusted at any angle in between. The edge of the disc forms a face seal with the elastic valve seat (rubber or PTFE), and the extended end of the valve stem is equipped with an anti-blowout structure. The two ends of the valve body can be connected by flanges, butt clamps, or butt welding. The overall height is small and the weight is light, making it suitable for large-diameter pipelines from DN50 to DN2000. When fully open, the flow resistance is close to that of the pipeline itself, and when closed, the elastic deformation of the valve seat achieves zero leakage.

[0030] Furthermore, a butterfly valve is installed at the outlet of main exhaust channel 4. By rotating the disc angle, it continuously adjusts the exhaust rate, thereby controlling the pressure level and flow distribution of the process gas within the chamber, meeting the stringent vacuum requirements (such as mTorr levels) during the etching process. Furthermore, during non-processing phases or emergency shutdowns, the butterfly valve can quickly close, disconnecting the chamber from the vacuum pump, preventing the backflow of external gas or oil molecules, and protecting the cleanliness and vacuum integrity of the chamber.

[0031] In the process of adjusting the distribution of process gas flow field by butterfly valve, since the butterfly valve can only adjust the flow area of ​​the main exhaust channel 4 as a whole and change the average pressure in the cavity body 1, it cannot change the axial flow field shape fixed by the top air intake and the single exhaust at the bottom. No matter how the butterfly plate opening changes, only the central jet and the edge dead zone are enlarged or reduced at the same time, and the gas cannot be redistributed in space, resulting in the problem of concentration gradient and uneven etching in the radial direction of the wafer 2.

[0032] To this end, the present invention provides an auxiliary air pumping channel 5 on the side wall of the cavity body 1, and the auxiliary air pumping channel 5 is connected to the cavity. Figure 1 and Figure 2 It is worth noting that Figure 1 In this example, the auxiliary exhaust channel 5 is in a closed state, and the gas cannot be extracted from the cavity body 1. Figure 2 In the example, the auxiliary exhaust channel 5 is in an open state, and the gas can be exhausted out of the cavity body 1 through it.

[0033] Furthermore, the number of auxiliary air extraction channels 5 is multiple, and the multiple auxiliary air extraction channels 5 are equidistantly distributed in an annular pattern along the circumference of the cavity body 1 (around the vertical center line of the cavity body 1), such as Figure 3 As shown, by cooperating with the main exhaust channel 4 and the butterfly valve, a controllable radial flow field is superimposed on the axial exhaust flow field to reconstruct the three-dimensional coupled flow field morphology, thereby spatially redistributing the process gas, eliminating the radial concentration gradient and edge dead zone of the wafer 2, and achieving a simultaneous improvement in the etching uniformity of the central area and the edge area of ​​the wafer.

[0034] Specifically, the auxiliary exhaust channel 5 is provided on the side wall of the chamber body 1, and the exhaust port (not numbered) of the auxiliary exhaust channel 5 is located between the upper surface of the wafer 2 and the top wall of the chamber body 1 in the axial direction. Figure 1 and Figure 2 As shown; in this example, the exhaust port is set between the upper surface of the wafer 2 and the top wall of the chamber body 1, which not only avoids the ion sheath protecting the uniformity of the plasma, but also covers the boundary layer, can immediately extract the high-concentration gas and create a radial pressure difference, guide the gas in the central area of ​​the wafer 2 to diffuse to the edge area, and cooperate with the main exhaust channel 4 to form a three-dimensional coupled flow field, thereby eliminating the radial concentration gradient and the edge dead zone in real time.

[0035] Among them, the ion sheath refers to the positive charge area left behind when the plasma contacts the solid surface because the electrons are first absorbed by the wafer surface, thus forming an "ion acceleration zone" with a thickness of only 1 to 3 mm and a strong electric field in front of the wafer surface. This ion acceleration zone determines the ion energy and incident angle. If it is disturbed, it will destroy the etching uniformity.

[0036] The boundary layer refers to a low-speed, high-gradient thin layer with a thickness of 5 to 15 mm formed in the area close to the surface of wafer 2 due to the viscosity of the gas when the gas flows through the surface of wafer 2. The gas concentration and velocity change dramatically, and it is a key area for controlling the pumping effect and redistribution of the gas flow field.

[0037] Furthermore, the number of the auxiliary exhaust channels 5 is N, and the N auxiliary exhaust channels 5 are arranged in an equidistant ring shape along the side wall of the chamber body 1 (around the vertical center line of the chamber body 1), so as to establish an exhaust flow field of the process gas in the radial direction of the wafer 2, such as Figure 2 As shown, in coordination with the main exhaust channel 4 and the main control valve, the three-dimensional coupled flow field within the chamber body 1 is reconstructed. In this example, N auxiliary exhaust channels 5 are provided and arranged in an equidistant annular pattern along the sidewalls of the chamber, with the goal of constructing a 360° annular exhaust array in the radial direction of the wafer 2. Through the local exhaust of each auxiliary exhaust channel 5, in coordination with the main exhaust channel 4, the traditional single axial flow field can be reconstructed into a three-dimensional coupled flow field that diffuses from the center of the wafer 2 to the edge of the wafer 2 and then to the sidewalls of the chamber body 1. This allows the high-concentration process gas in the central jet to be extracted in real time and replenished to the edge of the wafer 2, thereby eliminating radial concentration gradients and edge dead zones, and achieving uniform etching across the entire wafer.

[0038] It should be noted that, in one example, the central jet is located in the central area of ​​the wafer 2 and faces the exact center of the central area.

[0039] In the existing "top center air intake + bottom exhaust" ICP etching chamber, the volume concentration of the process gas (such as CF4 / O2) at the center jet (center area) is about 8 to 12%; the edge area is far away from the main exhaust channel 4 and is bypassed by the top center jet, so the volume concentration drops to 2 to 4%; due to the difference in gas volume concentration, the etching rate difference between the center area and the edge area of ​​the wafer 2 will be more than 10%.

[0040] The annular auxiliary exhaust channel 5 introduced in this application controls the gas flow rate from the radial direction of the wafer; by constructing a three-dimensional coupled flow field, the gas volume concentration in the central area of ​​the wafer 2 is reduced from 8 to 12% to 5.5 to 6.5%, and the gas volume concentration in the edge area of ​​the wafer 2 is increased from 2 to 4% to 5.0 to 6.0%; thereby, the existing concentration difference between the central area and the edge area is compressed from the original approximately 8% to less than or equal to ±1%, so that the gas concentrations in the central area and the edge area tend to be consistent, avoiding the problem of inconsistent etching rates in the central area and the edge area of ​​the wafer.

[0041] Furthermore, the number of the auxiliary air extraction channels 5 is set to a positive integer greater than or equal to 3. Specifically: When the number of the auxiliary air extraction channels 5 is an even number, for example, it can be 4, 6, 8 or 10, but is not limited to 4, 6, 8 or 10. Other values ​​are not described here. Figure 3 In the example, the number of auxiliary pumping channels 5 is set to 6. In this example, the number of auxiliary pumping channels 5 is set to an even number, which can make the pumping ports of the auxiliary pumping channels 5 arranged 180° symmetrically along the circumference. In this way, the auxiliary pumping channels 5 can be divided into several pairs, and the pumping ports of each pair of auxiliary pumping channels 5 form mirror-image low-pressure sinks in the radial direction, thereby canceling out the circumferential pressure waves and effectively suppressing the standing wave resonance mode, thereby achieving balanced regulation of the radial flow field or flow rate in the entire domain, and ensuring the symmetry and stability of the flow field within 360°, thereby significantly improving the etching uniformity of the center and edge areas of the wafer 2.

[0042] When the number of auxiliary pumping channels 5 is an odd number, for example, it can be 3, 5, 7 or 9, but is not limited to 3, 5, 7 or 9, and other values ​​are not repeated here. In this example, the angular spacing of the pumping ports relative to the auxiliary pumping channels 5 is a non-integer 180°, which can provide standing wave resonance conditions when circular symmetry is destroyed, and can completely suppress radial standing wave resonance and the concentration fluctuations caused by it; at the same time, there is no symmetrical sink in any direction of the odd array, which facilitates independent fine-tuning of the pumping flow of each pumping port to achieve asymmetric flow compensation; at the same time, it can easily avoid obstacles such as the gate valve or observation window of the cavity body 1, further improving the radial etching uniformity and layout flexibility of the wafer 2.

[0043] However, in the actual installation and layout process, when the number of auxiliary exhaust channels 5 is an even number, valve groups can be connected in parallel on the same path, with fewer pipelines, faster debugging, and lower costs. However, due to standing wave resonance, there will be fluctuations in the circumferential flow field. When the number of auxiliary exhaust channels 5 is an odd number, the standing wave resonance can be suppressed, thereby suppressing the fluctuations in the circumferential flow field, so that the flow field can be more uniform, and the control process is more flexible, but the valve groups and pipelines of the auxiliary exhaust channels 5 need to be laid out one by one, and the cost and maintenance workload are higher than the solution when the number of auxiliary exhaust channels 5 is an even number. It can be seen that when the number of auxiliary exhaust channels 5 is an even number, it is suitable for batch production with medium uniformity requirements. When the number of auxiliary exhaust channels 5 is an odd number, it is suitable for precision etching processes that require high adjustment accuracy and high flexibility. The specific type can be selected by those skilled in the art according to actual needs, and will not be elaborated here.

[0044] In one embodiment, the distance between the lower edge of the exhaust port and the upper surface of the wafer 2 in the axial direction of the wafer 2 is between 5 mm and 40 mm. Figure 1 and Figure 2 As shown, in the axial direction of the wafer, a vacuum zone covering 5mm to 40mm is formed. In this example, the axial distance between the lower edge of the vacuum port and the upper surface of the wafer 2 is strictly limited to 5mm to 40mm in order to meet the requirements of both plasma stability and gas dynamics. Specifically: The distances described below are all distances along the wafer axis, and are all described with the top surface of the wafer 2 as the zero point. Figure 1 and Figure 2 In the example, the axial direction of the wafer is the vertical direction.

[0045] In the region of 0 to 5 mm, which is the ion sheath (the typical thickness of the ion sheath is 1 to 3 mm), the electric field in this region can reach hundreds of volts / milliseconds, and any pumping disturbance will change the ion bombardment energy and the angle of incidence, thereby causing the morphology of the wafer 2 to change or deteriorate during the etching process. In this application, the lower edge of the pumping port is set higher than the ion sheath. During the actual etching process, the disturbance of the ion sheath gas can be effectively prevented, and the impact on the ion bombardment energy and the angle of incidence can be avoided. It is worth noting that the height of the pumping port in this application does not cover the area between 3 mm and 5 mm. This is an intentional transition zone to keep the pumping zone away from the ion sheath, to prevent the gas trajectory from deflecting and the edge focusing effect from reaching the ion sheath, thereby destroying the etching uniformity. If the pumping is performed in this transition zone, the electric field and the flow field will be disturbed at the same time, resulting in double uncertainty.

[0046] In the 5 to 15 mm area, this area is the gas boundary layer, in which the gas flow rate is the lowest and the gas concentration gradient in the central area and the edge area is the largest; in this application, the exhaust port is set in this area to directly extract the high-concentration gas in the central area to move to the low-concentration edge area, so as to establish a controllable radial pressure difference and effectively balance the concentration gradient between the central area and the edge area.

[0047] The lower edge height of the exhaust port in the present application is set to be in the range of 5mm to 40mm, so that it can cover the gas boundary layer of 5 to 15mm and the area above the gas boundary layer, that is, the area between 15mm and 40mm. For example, the height of the exhaust port can be 5mm, 8mm, 10mm, 15mm, 20mm and 40mm, etc., but it is not limited to the above heights, which will not be repeated here; in this way, it can cooperate with the 5 to 15mm exhaust process to further expand the radial compensation range without hitting the top wall of the cavity body 1, avoiding gas backflow upward or backflow from the edge area to the center area; at the same time, it avoids contact with the ion sheath; ensuring that the three-dimensional coupled flow field can not only uniformly distribute the gas concentration on the wafer surface, but also will not cause additional disturbances to the plasma, and has practical commercial application value.

[0048] In the axial direction of the wafer, the exhaust port of the auxiliary exhaust channel 5 can be set to one layer, two layers, three layers or more layers. The change in the number of layers is actually to superimpose multiple layers of radial low-pressure sinks above the wafer 2. The low-pressure sink can be understood as, in the etching equipment, referring to an artificially created local low-pressure area in the cavity body 1, whose pressure is lower than the surrounding gas environment, thereby producing a suction effect on the surrounding gas, causing the gas to flow to this point and be extracted.

[0049] It is worth noting that the more layers of exhaust ports there are, the finer the axial exhaust gradient is. This can be understood as, from top to bottom, the first layer extracts a portion of gas from the central jet to the edge area of ​​the wafer, and the second layer extracts a portion of gas from the central jet to the edge area of ​​the wafer, and so on for subsequent layers. This can be figuratively described as "layered peak shaving." In this way, through multi-layer extraction, the high-concentration gas that originally only existed in the central jet is radially compensated and expanded layer by layer, and ultimately expanded to three-dimensional compensation for the entire process space. Experimental results show that in the process from no auxiliary exhaust channel 5 to a single-layer exhaust port for the auxiliary exhaust channel 5, and finally to two or more layers, the concentration difference between the center and edge areas of wafer 2 is reduced from 8% to ±1% for a single layer, and then to ±0.5% for two, three, or more layers.

[0050] In actual processes, the number of layers of the exhaust ports of the auxiliary exhaust channel 5 is different. Specifically: In one example, Figure 1 and Figure 2As shown, there are multiple auxiliary exhaust channels 5, and the exhaust ports of the multiple auxiliary exhaust channels 5 are arranged at the same height on the side wall of the cavity body 1 to form a single-layer annular structure. Specifically, the number of exhaust ports can be set to 3, 4, 5, 6, 7, 8, 9, 10 or more, preferably 8 or 9.

[0051] It is worth noting that the greater the number of gas extraction ports, the denser the 360° discrete low-pressure sink array can be formed along the circumference of the chamber body 1, thereby better regulating the gas flow field within the chamber body 1. However, it should be understood that as the number of gas extraction ports increases, the cost of the valve group and piping also increases linearly. The specific selection can be adjusted by those skilled in the art based on the actual etching process accuracy requirements, and will not be further elaborated here.

[0052] In another example, Figure 3 As shown, there are multiple auxiliary pumping channels 5, and the multiple auxiliary pumping channels 5 are arranged at at least two different heights of the side wall of the chamber body 1 to form at least two layers of annular structures; each layer of the annular structure includes at least multiple auxiliary pumping channels, which are used to form at least two layers of radial pumping flow fields in the axial direction of the wafer, such as Figure 4 As shown, the advantage of at least a two-layer setting over a single-layer setting is that two layers of annular exhaust ports at different heights form a discrete low-pressure sink array with an axial gradient distribution above the wafer 2, which can "layer and peak" the gas concentration profile at a process pressure of 5 to 50 mTorr, further compressing the radial concentration difference of ±1% that can only be achieved in a single layer to ±0.5%, and at the same time reducing the edge retention layer thickness from 8mm to 10mm to 3mm to 4mm, effectively eliminating the micro-groove defects at the top of the double-layer groove.

[0053] In addition, the upper exhaust port directs the high-concentration gas in the upper part of the boundary layer to move rapidly from the high-concentration area in the central area to the low-concentration area in the edge area. In addition to supplementing the outward-moving gas function of the upper exhaust port, the lower exhaust port also has the function of sucking by-products inside the groove, realizing the three-dimensional compensation of "upper extraction and lower supplementation"; but at the same time, at least two layers of exhaust ports can independently adjust the flow rate, the fault redundancy is improved, the number of valve groups and pipelines is also doubled relative to a single layer, and the cost increases by about 60% to 80%. Therefore, when the number of local layers is local, it is necessary to make a comprehensive trade-off based on the process window and economic efficiency, which will not be elaborated here.

[0054] The edge retention layer refers to the annular area formed between the outer edge of the wafer 2 and the wall of the chamber body 1 in the horizontal direction. Because the edge retention layer is far away from the bottom main exhaust channel 4 and is affected by the detour of the central jet, the gas flow rate is significantly reduced, forming a low-flow, high-concentration, and easily accumulated reaction by-products and polymer retention boundary layer. This layer is usually between 5 mm and 10 mm thick. If it is not removed in time, it will lead to: on the one hand, the process gas concentration in the edge area is continuously high, causing etching rate differences; on the other hand, it will form an "edge dead zone", causing micro-groove defects to appear at the top of high aspect ratio grooves. In this application, the exhaust port setting of the auxiliary exhaust channel 5 in one or at least two layers can specifically reduce the thickness of the edge retention layer from 8 to 10 mm to 3 mm to 4 mm, effectively eliminating the micro-groove defects at the top of the groove. At the same time, it can prevent the deposition of by-products or polymers in this area, resulting in particulate contamination or sidewall roughness.

[0055] In the layout of at least two layers of the air extraction ports of the auxiliary air extraction channel 5, there are also different configurations, as follows: The following takes the auxiliary air extraction channel 5 having two air extraction ports as an example.

[0056] In a specific embodiment, Figure 4 As shown, the number of the auxiliary air pumping channels contained in each layer of the annular structure is consistent to form at least two identical radial air pumping flow fields. In the air pumping ports of the two layers of auxiliary air pumping channels 5, the number of air pumping ports in each layer is set to a plurality, and the number of air pumping ports in the two layers is consistent, for example, it can be 3, 4, 5, 6, 7, 8, 9, 10 or more, preferably 8 or 9, that is, when the number of air pumping ports in the upper layer of auxiliary air pumping channels 5 is 8 or 9, the number of air pumping ports in the lower layer of auxiliary air pumping channels 5 is also 8 or 9.

[0057] In this embodiment, the number of exhaust ports in the two layers is set to be exactly the same in order to form two completely mirrored radial low-pressure fields above the wafer 2: the exhaust intensity, circumferential phase and circumferential density of the two layers are exactly the same, so that neither the flow field distortion caused by axial misalignment nor the additional eddy current or gas concentration mutation caused by the difference between layers is avoided; this "double copy" structure enables the axial and radial coupled flow fields to remain highly symmetrical, and only one calibration is required to control the two layers at the same time, which is simple to debug and suitable for advanced node etching with extremely high uniformity requirements and narrow process windows; at the same time, the radial concentration gradient difference of the entire wafer 2 can be ultimately controlled to within ±0.5%.

[0058] In a specific embodiment, the number of auxiliary exhaust channels contained in the two adjacent layers of the annular structure increases layer by layer from top to bottom along the axial direction of the wafer to form two different radial exhaust flow fields. In the exhaust ports of the two layers of auxiliary exhaust channels 5, the number of exhaust ports in each layer is set to be several, and the number of exhaust ports in the two layers is inconsistent. For example, the number of exhaust ports in the upper layer and the lower layer can be 3, 4, 5, 6, 7, 8, 9, 10 or more; however, in the actual layout, the number of exhaust ports in the upper layer is 6, and the number of exhaust ports in the lower layer is 9; the advantage of such a setting is that the upper layer forms a stronger single-point suction with fewer but widely spaced confluence points, which can quickly reduce the high concentration in the center, and the lower layer forms a fine radial gradient with denser low-pressure confluence points, further compensating for the edge gas-deficient area. Two layers of low-pressure sinks with different densities are superimposed axially, which not only suppresses the central jet but also fully entrains the edge retention layer, so that the radial concentration gradient of the entire wafer 2 is ultimately controlled within ±0.5%.

[0059] Of course, in other specific embodiments, the exhaust ports can also be set to 3 layers or more layers, and there are different configurations in the 3 layers. For example, in one example, the number of exhaust ports in each layer is the same, for example, they are all set to 8 or 9; in another example, the number of exhaust ports increases layer by layer from top to bottom in the wafer axis, for example, the upper layer is set to 6, the middle layer is set to 8, and the lower layer is set to 9; in the third example, the number of exhaust ports in the upper and lower layers is the same, and the number of exhaust ports in the middle layer is inconsistent with that of the upper and lower layers, for example, the number of exhaust ports in the upper and lower layers is set to 6, and the number of exhaust ports in the middle layer is set to 8 or 9.

[0060] In one embodiment, Figure 1 and Figure 2 As shown, the gas outlet of the auxiliary exhaust channel 5 is connected to the auxiliary control valve (not shown), the auxiliary control valve is arranged outside the chamber body 1, the gas outlet and the exhaust port are arranged opposite to each other, and the auxiliary control valve extracts the process gas in the chamber body 1 through the auxiliary exhaust channel.

[0061] In this example, an auxiliary pumping channel is opened on the side wall of the cavity and an independent auxiliary control valve is connected to the outside in order to create a finely adjustable radial low-pressure sink on the periphery of the wafer 2; this layout upgrades the "whole cavity coarse adjustment" that could only be completed by the bottom main pumping to "partition fine adjustment", which not only avoids the disturbance to the central plasma, but also can extract high-concentration gas in real time at the edge, thereby cooperating with the main pumping channel 4 to reconstruct the three-dimensional coupled flow field and eliminate the radial concentration gradient and edge dead zone.

[0062] During operation, after the auxiliary control valve opens, the auxiliary pumping channel creates a localized low pressure on the outer side of the chamber wall. Driven by the radial pressure differential, gas within the chamber body 1 is continuously extracted from the auxiliary pumping channel's exhaust port. The extraction flow rate is independently controlled by the auxiliary control valve opening. By synchronously adjusting the auxiliary control valves of N auxiliary pumping channels, the gas distribution in the center and edge areas of wafer 2 can be dynamically balanced over a 360-degree range, achieving closed-loop flow field management with "extraction and replenishment."

[0063] It is worth noting that the auxiliary control valve can be a butterfly valve, but is not limited to a butterfly valve. The auxiliary exhaust channel is connected to an external vacuum pump, and the butterfly valve is located in the path of gas movement to control the gas flow. N auxiliary exhaust channels can be connected to the same vacuum pump, and the main exhaust channel 4 can also be connected to the auxiliary exhaust channel on the same vacuum pump. In addition, the position arrangement of the swing valve, the main exhaust channel 4, and the vacuum pump is consistent with the position arrangement of the butterfly valve, the auxiliary exhaust channel, and the vacuum pump, and will not be repeated here.

[0064] Moreover, the combination of the butterfly valve, auxiliary exhaust channel and vacuum pump in the present invention, and the coordination of the combination of the swing valve, main exhaust channel 4 and vacuum pump can also be used to adjust the pressure in the cavity body 1 and keep the pressure in the cavity body 1 constant. Specifically, when the combination of the swing valve, main exhaust channel 4 and vacuum pump remains unchanged, when the pressure in the cavity body 1 increases, the opening of the auxiliary exhaust channel is increased by adjusting the butterfly valve, and the exhaust volume at the auxiliary exhaust channel is increased, thereby achieving the effect of reducing the pressure in the cavity body 1; when the pressure in the cavity body 1 decreases, the opening of the auxiliary exhaust channel is reduced by adjusting the butterfly valve, and the exhaust volume at the auxiliary exhaust channel is reduced, thereby achieving the effect of increasing the pressure in the cavity body 1. Conversely, the combination of the butterfly valve, auxiliary exhaust channel and vacuum pump remains unchanged, and the effect of adjusting the pressure in the cavity body 1 can also be achieved by adjusting the swing valve, which will not be repeated here.

[0065] Preferably, the combination of the butterfly valve, the auxiliary exhaust channel and the vacuum pump in the present application cooperates with the combination of the swing valve, the main exhaust channel 4 and the vacuum pump, which can be used for pressure regulation in the cavity body 1 with inconsistent air intake volume, and can also be used for pressure regulation in the cavity body 1 with consistent air intake volume, which will not be repeated here.

[0066] The swing valve consists of a pendulum-shaped gate, a valve seat, a valve stem, and a drive mechanism. The gate is a curved or fan-shaped metal plate that is opened and closed by the reciprocating swing of the valve stem (usually 60° to 90°). The valve seat is a replaceable carbide or welded overlay. When the gate swings into position, it makes linear contact with the valve seat, forming a metal-to-metal seal. The valve body has a straight or inclined flow path, a short length, low opening and closing torque, and is resistant to erosion. It is commonly used in conditions involving particles or high temperatures and high pressures. Available in diameters from DN100 to DN1200, it can be mounted horizontally or vertically, and can be actuated manually, pneumatically, or electrically.

[0067] In one embodiment, a control device is further included, which is communicatively connected to the main control valve and the auxiliary control valve and is used to control the main control valve and the auxiliary control valve to work together to adjust the flow field distribution in the process chamber.

[0068] Herein, the control device can be understood as a host computer.

[0069] In actual use, the auxiliary air extraction channel has different configurations, such as an independently provided through hole with a rectangular cross-section or an L-shaped through hole; or a composite channel structure, specifically: In the first example, Figure 1 and Figure 2 As shown, the independently arranged channel cavity is a rectangular through hole with a horizontal cavity. In this configuration, the channel cavity height (vertical direction) of the auxiliary air extraction channel is between 1.5mm and 4mm, for example, it can be 1.5mm, 2mm, 2.5mm, 3.5mm, or 4mm, but it is not limited to the above dimensions and will not be repeated here.

[0070] In this example, the secondary exhaust channel is made into a horizontal rectangular slit with a height of 1.5 mm to 4 mm, which can instantly form a high-speed low-pressure sink within the boundary layer. This provides sufficient radial pressure difference and avoids interference between low-pressure sinks caused by excessive width. At the same time, it can prevent particle blockage and ensure that the radial airflow is precisely controllable.

[0071] It is worth noting that in the three-dimensional structure, the cavity of the through hole is cylindrical, but is not limited to a cylindrical shape.

[0072] In the second example, Figure 5 As shown, the independently arranged cross-sectional channel cavity is an L-shaped through hole, which includes a transverse section 51 and a vertical section 52, wherein the transverse section 51 is used to connect the inner cavity of the cavity body 1 and the vertical section 52. The transverse section 51 is horizontally arranged on the wall of the cavity body 1, and the vertical section 52 is vertically arranged on the wall of the cavity body 1. In this configuration, the cavity height of the transverse section 51 is between 1.5 mm and 4 mm, for example, it can be 1.5 mm, 2 mm, 2.5 mm, 3.5 mm, 4 mm, but it is not limited to the above dimensions, and will not be repeated here. The cavity height of the vertical section 52 is between 40 mm and 80 mm, for example, it can be 40 mm, 50 mm, 60 mm, 70 mm, 80 mm, but it is not limited to the above dimensions, and will not be repeated here.

[0073] In this example, the height of the horizontal section 51 of the L-shaped through hole is set to 1.5 mm to 4 mm to form a slit throttling area, which can instantly establish a controllable radial pressure difference in the boundary layer above the wafer 2; the vertical section 52 height of 40 mm to 80 mm provides sufficient airflow buffering and isobaric space, so that the flow velocity at the horizontal slit outlet is uniform and the flow direction is stable, and cooperates with the main exhaust at the bottom to reconstruct the three-dimensional coupled flow field, which not only improves the exhaust efficiency but also avoids disturbing the plasma sheath.

[0074] Furthermore, in one example, Figure 6 As shown, in the L-shaped through hole, there is one vertical segment 52 and several transverse segments 51, for example, two, three, or more. In this configuration, the several transverse segments 51 are arranged in the same vertical direction and are respectively connected to the vertical segment 52, and the several transverse segments 51 are not connected to each other.

[0075] In the third example, Figure 7 As shown, the auxiliary air pumping channel is a composite channel structure, which includes a first channel section 53, a second channel section 54 and a third channel section 55 which are connected in sequence. The channel cavity of the second channel section 54 is an annular structure (in a three-dimensional structure), and the first channel section 53 is used for connecting the second channel section 54 with the inner cavity of the cavity body 1. The number of the first channel sections 53 is set to be several, for example, it can be 3, 4, 5, 6, 7, 8 or 9; and several second channel sections 54 are arranged in an equidistant annular shape along the wall of the cavity body 1, and there is no communication between two adjacent second channel sections 54; the third channel section 55 is used for connecting the second channel section 54 with the auxiliary control valve, and the number of the third channel sections 55 is set to M, where M is a positive integer greater than or equal to 1, for example, it can be 1, 2, 3 or more, preferably 1.

[0076] The first channel section 53 is connected to the inner ring wall of the annular structure, and the third channel section 55 is connected to the lower end surface of the second channel section 54 .

[0077] In this example, a composite channel structure of "first channel section 53 + annular second channel section 54 + third channel section 55" is adopted to first converge several originally scattered independent exhaust ports into a circumferential annular cavity, and then centrally connect them through one or several main pipes: the annular second channel section 54 forms a 360° uniform low-pressure ring in the wall of the cavity body 1 to ensure symmetrical circumferential exhaust intensity; the first channel section 53 uses several micropores (or slits) to uniformly draw the gas above the wafer 2 into the annular cavity to avoid local over-extraction; the third channel section 55 is connected to the external valve group with at least one outlet, which can reduce the number of valve groups from several to at least one, significantly reducing external pipelines, valve bodies and sealing points, reducing the risk of particle contamination, simplifying debugging and maintenance, while retaining the ability to fine-tune the radial flow field, and realizing efficient three-dimensional coupled flow field reconstruction of "multi-point exhaust + single-ring convergence + centralized control".

[0078] Of course, in other examples, the auxiliary air extraction channel is not limited to being a through hole, but may also be a tubular structure, preferably a through hole.

[0079] In one embodiment, the suction port of the auxiliary suction channel is arranged horizontally to generate horizontal suction, such as Figure 1 and Figure 2 In this embodiment, the suction direction is parallel to the wafer 2, which can form a symmetrical, low-disturbance radial pumping field in the circumferential direction, quickly removing high-concentration gas at the edge without disturbing the ion sheath, ensuring uniform plasma concentration in the center and edge areas of the wafer.

[0080] In one embodiment, the extension line of the central axis of the exhaust port of the auxiliary exhaust channel 5 is tilted with the axial direction of the wafer 2 to form an angle, the angle being between 20° and 60°, and the exhaust port is tilted upward. Figure 8 As shown, the inclination angle is between 20° and 60°, for example, it can be 20°, 30°, 40°, 50° and 60°, but it is not limited to 20°, 30°, 40°, 50° and 60°, which will not be repeated here.

[0081] In this embodiment, the upward inclination angle of the exhaust port of 20° to 60° generates an oblique downward suction airflow during exhaust, which not only avoids the sensitive area of ​​the ion sheath, but also uses the oblique momentum to directly guide the central jet to the edge, thereby strengthening the three-dimensional coupled flow field in the central area, edge area and side of the wafer 2, making the edge retention layer thinner and the concentration gradient smaller, thereby obtaining higher radial uniformity and deeper groove bottom cleaning effect at the same pumping speed.

[0082] Of course, in other embodiments, for example, in the multi-layer configuration of the auxiliary air extraction channel 5 , the horizontal setting of the air extraction port and the inclined setting of the air extraction port can be set separately or in combination, which will not be repeated here.

[0083] In one embodiment, the process chamber with controllable gas flow field further includes: Gas sensors (not shown) are located within chamber body 1, preferably in the center and edge regions of the wafer. Multiple gas sensors are provided to monitor gas concentrations at different locations in real time. These gas sensors can be, but are not limited to, hydrogen or carbon dioxide sensors.

[0084] The pressure sensor (not shown) is provided on or outside the cavity body 1 and is used to monitor the air pressure of the cavity body 1 in real time.

[0085] The processor (not shown) is provided on or outside the chamber body 1 and is electrically connected to the gas sensor, pressure sensor, butterfly valve and swing valve. It is used to receive the detection signal of the gas sensor and calculate the corresponding gas concentration according to a preset algorithm.

[0086] Specifically, the processor controls the start-up of the swing valve or butterfly valve or not based on the gas concentration signal collected by the gas sensor. When the concentration of the central area and the edge area is detected to be consistent, or the air pressure in the cavity body 1 is normal, the swing valve or butterfly valve will not be started. When the concentration of the central area and the edge area is detected to be inconsistent, or the air pressure in the cavity body 1 is abnormal (too high or too low), the swing valve or butterfly valve will be started. It is worth noting that when several butterfly valves are started, the opening of several auxiliary exhaust channels can be controlled to change in a consistent manner or inconsistently. The specific opening size can be adjusted in real time according to the different gas concentrations, which will not be described here.

[0087] In response to the problems existing in the prior art, an embodiment of the present invention further provides a plasma processing device, including the process chamber with controllable gas flow field and a carrier platform, wherein the carrier platform is used to carry the wafer 2.

[0088] In addition, the process chamber with controllable gas flow field in the present invention is not only suitable for etching equipment included in plasma processing equipment, but can also be seamlessly extended to chemical vapor deposition (CVD), physical vapor deposition (PVD) and atomic layer deposition (ALD) equipment. Through the same radial and axial coupled flow field control, the deposition gas concentration is uniformed to ensure film thickness consistency and step coverage. It is also suitable for photoresist stripping equipment for quickly and evenly removing residual polymers or metal etching byproducts to avoid edge residues and redeposition defects.

[0089] While embodiments of the present invention have been described in detail above, it will be apparent to those skilled in the art that various modifications and variations of these embodiments are possible. However, it should be understood that such modifications and variations are within the scope and spirit of the present invention. Furthermore, the invention described herein is susceptible to other embodiments and may be practiced or implemented in a variety of ways.

Claims

1. A process chamber with controllable gas flow field, characterized in that: include: The cavity body has a cavity for carrying the wafer; an air inlet channel, communicating with the chamber and configured to introduce a process gas into the chamber; A main exhaust channel is provided at the bottom of the chamber body and communicates with the chamber; the main exhaust channel is connected to a main control valve and is used to establish an exhaust flow field of process gas in the axial direction of the wafer; An auxiliary exhaust channel is provided on the side wall of the chamber body and is in communication with the chamber, and the horizontal planes of the exhaust ports of the auxiliary exhaust channel are all located above the wafers carried thereon, and the auxiliary exhaust channel is connected to a corresponding auxiliary control valve for establishing an exhaust flow field of the process gas in the radial direction of the wafer; there are multiple auxiliary exhaust channels, and the exhaust ports of the multiple auxiliary exhaust channels are arranged on the side wall of the chamber body in an annular structure; A control device is communicatively connected with the main control valve and the auxiliary control valve, and is used to control the main control valve and the auxiliary control valve to work in coordination so as to adjust the flow field distribution in the process chamber.

2. The process chamber with controllable gas flow field according to claim 1, characterized in that: The exhaust ports of the plurality of auxiliary exhaust channels are arranged at the same height of the side wall of the cavity body to form a single-layer annular structure, which is used to establish a single-layer radial exhaust flow field in the cavity body.

3. The process chamber with controllable gas flow field according to claim 1, characterized in that: Multiple auxiliary exhaust channels are arranged at at least two different heights on the side wall of the cavity body to form at least two layers of annular structures; each layer of the annular structure includes at least multiple auxiliary exhaust channels, which are used to form at least two layers of radial exhaust flow fields in the axial direction of the wafer.

4. The process chamber with controllable gas flow field according to claim 3, characterized in that: The number of the auxiliary air pumping channels included in each layer of the annular structure is consistent, so as to form at least two identical radial air pumping flow fields.

5. The process chamber with controllable gas flow field according to claim 3, characterized in that: The number of the auxiliary exhaust channels included in two adjacent layers of the annular structure increases layer by layer from top to bottom along the axial direction of the wafer to form two different radial exhaust flow fields.

6. The process chamber with controllable gas flow field according to claim 1, characterized in that: In the axial direction of the wafer, the distance between the lower edge of the exhaust port and the upper surface of the wafer is between 5 mm and 40 mm.

7. The process chamber with controllable gas flow field according to claim 1, characterized in that: The auxiliary air pumping channel is an independent channel structure, and the channel cavity height of the channel structure is between 1.5 mm and 4 mm.

8. The process chamber with controllable gas flow field according to claim 1, characterized in that: The auxiliary air pumping channel is an independent channel structure and has an L-shaped structure. The auxiliary air pumping channel includes a transverse section and a vertical section. The transverse section is used to connect the inner cavity of the cavity body and the vertical section. Among them, the channel cavity height of the horizontal section is between 1.5mm and 4mm; the lower end opening of the vertical section is arranged on the bottom wall of the cavity body and is connected to the auxiliary control valve, and the channel cavity height of the vertical section is between 40mm and 80mm.

9. The process chamber with controllable gas flow field according to claim 1, characterized in that: The auxiliary air pumping channel is a composite channel structure, which includes a first channel section, a second channel section and a third channel section which are connected in sequence. The channel cavity of the second channel section is an annular structure. The first channel section is used for connecting the second channel section with the inner cavity of the cavity body. There are several first channel sections, and several second channel sections are arranged in an equidistant annular pattern along the wall of the cavity body; the third channel section is used for connecting the second channel section with the auxiliary control valve. There are M third channel sections, where M is a positive integer greater than or equal to 1, wherein the first channel section is connected to the inner annular wall of the annular structure, and the third channel section is connected to the lower end face of the second channel section.

10. The process chamber with controllable gas flow field according to claim 1, characterized in that: The extension line of the central axis of the exhaust port of the auxiliary exhaust channel is arranged perpendicular to the axial direction of the wafer.

11. The process chamber with controllable gas flow field according to claim 1, characterized in that: The extension line of the central axis of the exhaust port of the auxiliary exhaust channel is tilted to the axial direction of the wafer and forms an angle. The size of the angle is between 20° and 60°, and the exhaust port is tilted upward.

12. The process chamber with controllable gas flow field according to claim 1, characterized in that: The main control valve is a swing valve.

13. The process chamber with controllable gas flow field according to claim 1, characterized in that: The auxiliary control valve is a butterfly valve.

14. The process chamber with controllable gas flow field according to claim 1, characterized in that: The main air pumping channel and the auxiliary air pumping channel share a vacuum pump.

15. The process chamber with controllable gas flow field according to claim 1, characterized in that: The main air pumping channel and the auxiliary air pumping channel are respectively connected to different vacuum pumps.

16. A plasma processing device, characterized in that: It comprises a process chamber with controllable gas flow field as claimed in any one of claims 1 to 15, and a carrying platform, wherein the carrying platform is used to carry a wafer.

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