Wafer processing device

Abstract

The utility model discloses a wafer processing device, and belongs to the technical field of semiconductor processing equipment.The wafer processing device in the embodiment of the utility model at least comprises a reactor, the reactor comprises a shell and a top cover assembly which are connected, at least one cavity is formed between the shell and the top cover assembly, and the top cover assembly comprises a cover plate, a top plate and a fixing structure; the cover plate is connected with the shell and covers the cavity; the top plate is arranged in the cavity; the fixing structure is connected with the cover plate and supports the top plate, so that the top plate is separated from the cover plate; the fixing structure comprises a fixing ring and a connecting piece, the fixing ring is arranged around the top plate, and the inner edge of the fixing ring is connected with the side, away from the cover plate, of the top plate; the connecting piece is respectively connected with the retaining ring and the cover plate. The top plate is annularly supported through the retaining ring, so that the temperature uniformity in the circumferential direction of the top plate is good, the influence of the temperature of the cover plate on the top plate is reduced, and the service life of the top plate is prolonged.

Description

Technical Field

[0001] The present application belongs to the technical field of semiconductor processing equipment, and specifically relates to a wafer processing device. Background Art

[0002] Wafer processing equipment is one of the key equipment in the semiconductor manufacturing process, which is used to perform various process steps on wafers to manufacture integrated circuits and other microelectronic devices.

[0003] Wafer processing devices are usually equipped with a top plate to isolate the reaction gas from the inner wall of the cover plate to prevent the cover plate from being corroded or to prevent the low temperature of the cover plate from affecting the thermal field in the chamber. However, currently the top plate needs to be mounted on the cover plate, and a low temperature area is easily formed at the holding point or holding area, resulting in an excessively large temperature gradient near the holding area, making it easy for large thermal stress to be generated inside the top plate, resulting in the possibility of deformation or cracking of the top plate. Utility Model Content

[0004] Purpose of the utility model: The embodiment of the present application provides a wafer processing device, which aims to overcome the technical problem that there is an excessively large temperature gradient near the holding area of ​​the top plate and the cover plate, causing the top plate to deform or break.

[0005] Technical solution: The embodiment of the present application provides a wafer processing device, the wafer processing device includes at least one reactor, the reactor includes a shell and a top cover assembly connected to each other, there is at least one chamber between the shell and the top cover assembly, and the top cover assembly includes:

[0006] a cover plate, the cover plate being connected to the shell and sealing the chamber;

[0007] A top plate, the top plate being disposed in the chamber;

[0008] A holding structure, the holding structure is connected to the cover plate and supports the top plate so that the top plate is spaced apart from the cover plate;

[0009] Wherein, the retaining structure comprises: a retaining ring, the retaining ring is arranged around the top plate, and the inner edge of the retaining ring is connected to a side of the top plate away from the cover plate;

[0010] A connecting piece is used to connect the retaining ring and the cover plate respectively.

[0011] In some embodiments, the top plate and the cover plate are spaced apart along a first direction, the retaining ring has a first orthographic projection on the cover plate along the first direction, and the top plate has a second orthographic projection on the cover plate along the first direction, and the first orthographic projection is at least partially located outside the second orthographic projection.

[0012] In some embodiments, the connecting member includes a connecting rod and an elastic part. The connecting rod is connected to the cover plate. The elastic part has a first end and a second end oppositely arranged in a first direction. The first end is connected to the connecting rod, and the second end is connected to the holding ring. The elastic part is configured to generate elastic deformation when the holding ring moves relative to the connecting rod in the first direction.

[0013] In some embodiments, the holding ring is provided with an assembly groove and a through hole penetrating the bottom of the assembly groove. The connecting rod passes through the through hole from the assembly groove. The elastic part is received in the assembly groove and sleeved on the connecting rod. There is a clearance fit between the connecting rod and the assembly groove or the through hole.

[0014] In some embodiments, the connecting member further includes a heat insulation gasket. The heat insulation gasket is arranged in the assembly groove, and the second end is connected to the assembly groove through the heat insulation gasket.

[0015] In some embodiments, the holding ring is configured to be made of graphite material and is configured with a silicon carbide or tantalum carbide coating.

[0016] In some embodiments, the top cover assembly further includes a limiting block. The limiting block is arranged between the top plate and the cover plate. The limiting block is used to separate the top plate and the cover plate. The limiting block is made of an insulating and heat-insulating material.

[0017] In some embodiments, the top cover assembly is provided with an air inlet channel communicating with the chamber, and the bottom wall of the housing is provided with an exhaust hole;

[0018] The reactor further includes:

[0019] A wafer stage, arranged in the chamber. The wafer stage and the top plate define at least one reaction chamber;

[0020] An exhaust structure, arranged in the chamber and having an exhaust channel surrounding the wafer stage. The exhaust channel communicates the reaction chamber with the exhaust hole. The air inlet channel can introduce external gas into the reaction chamber; wherein, the holding ring is provided with an arc-shaped guiding surface, and the arc-shaped guiding surface is located between the reaction chamber and the exhaust channel and can guide the gas in the chamber to the exhaust channel.

[0021] In some embodiments, the exhaust structure includes a first channel wall and a second channel wall. The first channel wall is arranged around the outer periphery of the second channel wall and is spaced from the second channel wall to form the exhaust channel. The first channel wall is arranged on the side of the holding ring away from the top plate, and a purging channel communicating with the exhaust channel is formed by the space between the first channel wall and the holding ring;

[0022] Relative to the bottom wall of the shell, the height of the purge channel is lower than that of the reaction chamber.

[0023] In some embodiments, the purge channel has an inlet end and an outlet end, the outlet end is located on the inner side of the first channel wall, the inlet end is located on the outer side of the first channel wall, and relative to the bottom wall, the inlet end is not lower than the outlet end.

[0024] Beneficial effect: A wafer processing device in an embodiment of the present application includes a shell and a top cover assembly connected to each other, the shell has a chamber, and the top cover assembly includes: a top plate, a cover plate and a holding structure, the top plate is arranged in the chamber; the cover plate is arranged on the side of the top plate away from the chamber, the cover plate is connected to the shell and covers the chamber; the holding structure is connected to the cover plate, and supports the top plate so that the top plate and the cover plate are spaced apart; the holding structure includes: a holding ring and a connecting piece, the holding ring is arranged around the top plate, the inner edge of the holding ring is connected to the side of the top plate away from the cover plate; the connecting piece connects the holding ring and the cover plate respectively. An annular support is formed by the holding ring, so that the temperature uniformity of the top plate in the circumferential direction is good, local low temperature will not be generated, thermal stress differences in the holding position of the top plate are avoided, and the risk of deformation or rupture of the top plate due to holding is avoided. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings required for use in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For those skilled in the art, other drawings can be obtained based on these drawings without paying any creative work.

[0026] Figure 1 A half-section schematic diagram of a reactor of a wafer processing device in an embodiment of the present application;

[0027] Figure 2 for Figure 1 A local enlarged schematic diagram of the middle A;

[0028] Figure 3 This is a schematic diagram of the three-dimensional structure of the top cover assembly in the embodiment of the present application;

[0029] Figure 4 This is a bottom view structural diagram of the top cover assembly in the embodiment of the present application;

[0030] Figure 5 for Figure 4 Schematic cross-sectional view in the middle BB direction;

[0031] Figure 6 for Figure 5 A partial enlarged schematic diagram of point C in the middle;

[0032] Reference numerals: 1, housing; 2, top cover assembly; 10, chamber; 21, top plate; 22, cover plate; 23, holding structure; 231, holding ring; 232, connecting member; X, first direction; 233, connecting rod; 234, elastic part; 2341, first end; 2342, second end; 2310, assembly groove; 2311, gap; 2312, through hole; 235, heat insulation gasket; 24, limiting block; 25, air inlet channel; 11, bottom wall; 100, reaction chamber; 110, exhaust hole; 3, wafer stage; 4, exhaust structure; 41, first channel wall; 42, second channel wall; 40, exhaust channel; 50, purge channel; 2313, arc guiding surface; 501, inlet end; 502, outlet end. Detailed implementation manners

[0033] The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative efforts belong to the scope of protection of the present application.

[0034] In the description of the present application, it should be understood that the orientation or positional relationship indicated by terms such as "inner", "outer", etc. is based on the orientation or positional relationship shown in the drawings, and is only for the convenience of describing the present application and simplifying the description, rather than indicating or implying that the device or component referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus should not be construed as a limitation to the present application. In the description of the present application, "a plurality of" means two or more, and at least one means one, two or more, unless otherwise specifically defined. Terms such as "first" and "second" are only used for convenient description and name the components or embodiments with numbers, and do not imply an important ranking between the components or embodiments.

[0035] It should also be noted that in the accompanying drawings of the specification of the present application, an arrow marked with X indicates the first direction. In the description of the present application, the first direction is introduced to more clearly understand the structure and relative positional relationship of each component in the wafer processing device.

[0036] As a prelude to the embodiments of the present application, in the reactor of a wafer processing apparatus, in order to prevent the reaction gas entering the reactor from directly contacting the cover plate, resulting in a large amount of parasitic products on the inner wall surface of the cover plate, a top plate is generally provided between the cover plate and the wafer stage. However, a cooling channel is usually provided inside the cover plate, and the cover plate is cooled by introducing an external cooling medium. Considering the current mounting method of the top plate on the cover plate, a low-temperature region is likely to form at the holding point or holding area on the top plate. On the one hand, the low-temperature region will affect the temperature of the top plate, resulting in the inability to perform in-situ cleaning of the top plate, thereby affecting the processing quality of the wafer. On the other hand, there will be an excessive temperature gradient near the holding area, making it easy to generate large thermal stress inside the top plate, causing the risk of deformation or rupture of the top plate.

[0037] In view of this, the embodiments of the present application provide a wafer processing apparatus, aiming to solve at least one of the above technical problems.

[0038] Please refer to Figures 1 to 6 As shown, the embodiments of the present application provide a wafer processing apparatus, which at least includes a reactor. The reactor includes a connected housing 1 and a top cover assembly 2. There is at least one chamber 10 between the housing 1 and the top cover assembly 2 for accommodating wafers and required processing media.

[0039] Specifically, the top cover assembly 2 includes: a cover plate 22, a top plate 21, and a holding structure 23. Among them, the cover plate 22 is connected to the housing 1 and seals the chamber 10. A cooling channel for the flow of an external cooling medium is usually provided inside the cover plate 22 for cooling the cover plate 22. The top plate 21 is disposed in the chamber 10 to protect the inner wall surface of the cover plate 22 from corrosion. The holding structure 23 is connected to the cover plate 22 and supports the top plate 21, so that the top plate 21 is spaced from the cover plate 22. Among them, the holding structure 23 includes: a holding ring 231 and a connecting member 232. The holding ring 231 is disposed around the top plate 21, and the inner edge of the holding ring 231 is connected to the side of the top plate 21 facing away from the cover plate 22. The connecting member 232 connects the holding ring 231 and the cover plate 22 respectively. The holding structure 23 composed of the connecting member 232 and the holding ring 231 can form an annular support on the side of the top plate 21 facing away from the cover plate 22 to position and support the top plate 21, and keep the top plate 21 not in direct contact with the cover plate 22, so that the temperature uniformity of the holding area of the top plate 21 is good in the circumferential direction, no local low temperature will be generated, and the risk of thermal stress difference at the holding position of the top plate 21 is avoided. Thus, the risk of deformation or rupture of the top plate 21 due to holding is avoided, and the service life of the top plate 21 is improved.

[0040] In some embodiments, please refer to Figure 2As shown, the top plate 21 and the cover plate 22 are arranged at an interval in the first direction X, and the first direction X can be understood as the height direction of the wafer processing device. The holding ring 231 has a first orthographic projection on the cover plate 22 along the first direction X, and the top plate 21 has a second orthographic projection on the cover plate 22 along the first direction X. At least part of the first orthographic projection is located outside the second orthographic projection, and the first orthographic projection and the second orthographic projection can be measured by the projection method. It should be understood that at least part of the first orthographic projection is located outside the second orthographic projection, that is, at least the outer edge of the side surface of the holding ring 231 facing the top plate 21 is located outside the top plate 21; wherein, the inner edge and the outer edge can be interpreted as the two opposite ends of the holding ring 231 in the radial direction on the surface facing the top plate 21. On the one hand, the outer edge area can provide an assembly space for the connecting member 232. On the other hand, there can be a gap 2311 between the outer edge of the holding ring 231 and the cover plate 22 to reserve a deformation space required for the thermal expansion of the top plate 21 to ensure the use state of the top plate 21.

[0041] In some embodiments, please refer to Figure 3 and Figure 4 As shown, the connecting member 232 includes a connecting rod 233 and an elastic part 234. The connecting rod 233 is connected to the cover plate 22. The elastic part 234 has a first end 2341 and a second end 2342 arranged oppositely in the first direction X. The first end 2341 is connected to the connecting rod 233, and the second end 2342 is connected to the holding ring 231. The elastic part 234 is arranged to generate elastic deformation when the holding ring 231 moves relative to the connecting rod 233 in the first direction X. Through the elastic support structure composed of the connecting rod 233 and the elastic part 234, the holding ring 231 and the cover plate 22 are connected. It should be understood that during the assembly of the top cover assembly 2, the elastic part 234 can provide more flexibility for the assembly of the top plate 21; at the same time, along the first direction X, the deformation margin of the elastic part 234 can provide a moving space for the top plate 21 to release the thermal expansion deformation, avoiding the risk of the top plate 21 being fixed too tightly and causing deformation of the top plate 21. In addition, in some embodiments, the first end 2341 of the elastic part 234 is connected to the connecting rod 233, and the second end 2342 is connected to the holding ring 231. The elastic part 234 can be a spring structure.

[0042] In some embodiments, please refer to Figure 2 、 Figure 5 and Figure 6As shown, the holding ring 231 is provided with an assembly groove 2310 and a through hole 2312 penetrating the bottom of the assembly groove 2310. The connecting rod 233 passes through the through hole 2312 from the assembly groove 2310. The elastic part 234 is received in the assembly groove 2310 and sleeved on the connecting rod 233. The connecting rod 233 is in clearance fit 2311 with the assembly groove 2310 or the through hole 2312. It should be understood that when the elastic part 234 is sleeved on the connecting rod 233, the contact area between the elastic part 234 and the holding ring 231 is smaller, and the heat conduction ability is lower. At the same time, the clearance 2311 between the connecting rod 233 and the assembly groove 2310 or the through hole 2312 further reduces the contact area between the connecting member 232 and the holding ring 231, thereby reducing heat loss. By providing the assembly groove 2310 and the through hole 2312 on the holding ring 231 to realize the accommodation and assembly of the connecting member 232, the space occupied by the chamber 10 is further reduced.

[0043] In some embodiments, the connecting member 232 further includes a heat insulation gasket 235. The heat insulation gasket 235 is disposed in the assembly groove 2310, and the second end 2342 is connected to the assembly groove 2310 through the heat insulation gasket 235. It should be understood that the heat insulation gasket 235 can be a quartz gasket. By connecting the second end 2342 to the inner wall of the assembly groove 2310 through the heat insulation gasket 235, the contact area between the connecting member 232 and the holding ring 231 is further reduced to avoid heat loss.

[0044] In some embodiments, the connecting rod 233 is threadedly connected to the cover plate 22, and the connection length of the connecting rod 233 can be adjusted by a thread (not shown in the figure) between the connecting rod 233 and the cover plate 22 to adjust the holding ring 231 in the first direction X, and further adjust the distance between the top plate 21 and the cover plate 22 to ensure that the installation of the top plate 21 will not be deformed, avoid the over-tight assembly of the top cover assembly 2, and shorten the service life of the top plate 21.

[0045] In some embodiments, the holding ring 231 is configured to be made of graphite and is provided with a silicon carbide or tantalum carbide coating. The silicon carbide or tantalum carbide coating mainly plays an anti-corrosion role. The holding ring 231 and the top plate 21 are made of the same graphite material to ensure temperature balance between the holding ring 231 and the top plate 21, reduce temperature difference, directly improve the service life of the top plate 21, and indirectly improve the temperature field distribution in the reaction chamber 100.

[0046] In some embodiments, please refer to Figure 5 and Figure 6As shown, the top cover assembly 2 further includes a limit block 24. The limit block 24 is disposed between the top plate 21 and the cover plate 22. The limit block 24 is used to separate the top plate 21 and the cover plate 22, and the limit block 24 is made of insulating and heat-insulating material. By providing the limit block 24, it is used to limit the movement stroke of the top plate 21 in the first direction X, avoiding over-tight assembly of the top cover assembly 2 and further shortening the service life of the top plate 21.

[0047] In some embodiments, please refer to Figure 1 and Figure 3 As shown, the top cover assembly 2 is provided with an air inlet passage 25 communicating with the chamber 10, and the bottom wall 11 of the housing 1 is provided with an exhaust hole 110; the reactor further includes: a wafer stage 3 and an exhaust structure 4. Among them, the wafer stage 3 is disposed in the chamber 10, and the wafer stage 3 and the top plate 21 define at least one reaction chamber 100; the exhaust structure 4 is disposed in the chamber 10 and has an exhaust passage 40 surrounding the wafer stage 3. The exhaust passage 40 communicates the reaction chamber 100 with the exhaust hole 110, and the air inlet passage 25 can introduce external gas into the reaction chamber 100; wherein, the retaining ring 231 is provided with an arc-shaped guiding surface 2313, and the arc-shaped guiding surface 2313 is located between the reaction chamber 100 and the exhaust passage 40 and can guide the gas in the chamber 10 to the exhaust passage 40. Through the arc-shaped guiding surface 2313 of the retaining ring 231, the flow direction of the reaction gas is changed, so that the reaction gas can be smoothly guided into the exhaust passage 40, avoiding the reaction gas remaining in the reaction chamber 100 and affecting the wafer quality.

[0048] In some embodiments, the exhaust structure 4 includes a first channel wall 41 and a second channel wall 42. The first channel wall 41 is disposed around the outer periphery of the second channel wall 42 and is spaced from the second channel wall 42 to form the exhaust passage 40. The first channel wall 41 is disposed on the side of the retaining ring 231 away from the top plate 21, and a purge passage 50 communicating with the exhaust passage 40 is formed between the first channel wall 41 and the retaining ring 231; relative to the bottom wall 11 of the housing 1, the height of the purge passage 50 is lower than that of the reaction chamber 100. Specifically, the height of the purge passage 50 and the reaction chamber 100 can be compared by using a scale measurement method, that is, there is a first height dimension H 1 between the bottom of the reaction chamber 100 and the bottom wall 11 of the housing 1, and there is a second height dimension H 2 between the top of the purge passage 50 and the bottom wall 11 of the housing 1, satisfying: H 2 <H 1 . It can be understood that the height of the purge passage 50 is lower than that of the reaction chamber 100, and the purge gas can pass through the purge passage 50 to reach the exhaust passage 40 and be discharged through the exhaust hole 110 without flowing back into the reaction chamber 100 and affecting the wafer production quality.

[0049] It should be understood that the gap 2311 of the purge channel 50 can be within 3 mm. On the one hand, it can provide a path for the purge gas to discharge. On the other hand, the purge channel 50 can provide a movement margin for the deformation of the top plate 21.

[0050] In some embodiments, please refer to Figure 2 As shown, the purge channel 50 has an inlet end 501 and an outlet end 502. The outlet end 502 is located inside the first channel wall 41, and the inlet end 501 is located outside the first channel wall 41. Relative to the bottom wall 11, the inlet end 501 is not lower than the outlet end 502. Specifically, the height of the inlet end 501 and the outlet end 502 can still be compared by using a scale measurement method, that is, there is a third dimension H between the inlet end 501 and the bottom wall 11 of the housing 1 3 , and there is a fourth dimension H between the outlet end 502 and the bottom wall 11 of the housing 1 4 , satisfying: H 4 ≤H 3 . The height of the inlet end 501 is not lower than that of the outlet end 502, which can prevent the reaction gas from entering the purge channel 50. Further, when the height of the inlet end 501 is not lower than that of the outlet end 502, the path of the purge channel 50 is ramp-shaped or stepped to prevent the reaction gas from entering the purge channel 50 and flowing back between the top plate 21 and the cover plate 22, causing pollution.

[0051] In the above embodiments, the descriptions of each embodiment have their own emphases. For the parts not detailed in a certain embodiment, reference can be made to the relevant descriptions of other embodiments.

[0052] The wafer processing apparatus provided by the embodiments of the present application has been introduced in detail above, and specific examples have been used to elaborate the principle and implementation manner of the present application. The description of the above embodiments is only used to help understand the technical solution and its core idea of the present application; those of ordinary skill in the art should understand that they can still modify the technical solutions recorded in the foregoing embodiments, or perform equivalent replacements for some of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the scope of the technical solutions of the embodiments of the present application.

Claims

1. A wafer processing device, characterized in that: The wafer processing device comprises at least one reactor, the reactor comprising a shell (1) and a top cover assembly (2) connected to each other, at least one chamber (10) being provided between the shell (1) and the top cover assembly (2), and the top cover assembly (2) comprising: a cover plate (22), the cover plate (22) being connected to the housing (1) and sealing the chamber (10); A top plate (21), the top plate (21) being disposed in the chamber (10); A holding structure (23), the holding structure (23) being connected to the cover plate (22) and supporting the top plate (21) so that the top plate (21) and the cover plate (22) are spaced apart; Wherein, the retaining structure (23) comprises: a retaining ring (231), the retaining ring (231) is arranged around the top plate (21), and the inner edge of the retaining ring (231) is connected to a side of the top plate (21) facing away from the cover plate (22); A connecting member (232), wherein the connecting member (232) respectively connects the retaining ring (231) and the cover plate (22).

2. The wafer processing device according to claim 1, characterized in that: The top plate (21) and the cover plate (22) are spaced apart along a first direction (X); the retaining ring (231) has a first orthographic projection on the cover plate (22) along the first direction (X); the top plate (21) has a second orthographic projection on the cover plate (22) along the first direction (X); and the first orthographic projection is at least partially located outside the second orthographic projection.

3. The wafer processing device according to claim 1, characterized in that: The connecting member (232) comprises a connecting rod (233) and an elastic portion (234); the connecting rod (233) is connected to the cover plate (22); the elastic portion (234) has a first end (2341) and a second end (2342) which are arranged opposite to each other in a first direction (X); the first end (2341) is connected to the connecting rod (233); the second end (2342) is connected to the retaining ring (231); and the elastic portion (234) is arranged to generate elastic deformation when the retaining ring (231) moves relative to the connecting rod (233) in the first direction (X).

4. The wafer processing device according to claim 3, characterized in that: The retaining ring (231) is provided with an assembly groove (2310) and a through hole (2312) penetrating the bottom of the assembly groove; the connecting rod (233) passes through the through hole (2312) from the assembly groove (2310); the elastic portion (234) is received in the assembly groove (2310) and sleeved on the connecting rod (233); the connecting rod (233) and the assembly groove (2310) or the through hole (2312) are clearance-matched.

5. The wafer processing device according to claim 4, characterized in that: The connecting member (232) further comprises a heat-insulating gasket (235), wherein the heat-insulating gasket (235) is disposed in the assembly groove (2310), and the second end (2342) is connected to the assembly groove (2310) via the heat-insulating gasket (235).

6. The wafer processing device according to claim 1, characterized in that: The retaining ring (231) is made of graphite material and is provided with a silicon carbide or tantalum carbide coating.

7. The wafer processing device according to claim 1, characterized in that: The top cover assembly (2) further comprises a limit block (24), wherein the limit block (24) is arranged between the top plate (21) and the cover plate (22), the limit block (24) is used to separate the top plate (21) and the cover plate (22), and the limit block (24) is made of an insulating and heat-insulating material.

8. The wafer processing device according to claim 1, characterized in that: The top cover assembly (2) is provided with an air intake passage (25) communicating with the chamber (10), and the bottom wall (11) of the shell (1) is provided with an exhaust hole (110); The reactor further comprises: A wafer carrier (3) is arranged in the chamber (10), wherein the wafer carrier (3) and the top plate (21) define at least one reaction chamber (100); An exhaust structure (4) is arranged in the chamber (10) and has an exhaust channel (40) surrounding the wafer carrier (3), wherein the exhaust channel (40) connects the reaction chamber (100) and the exhaust hole (110), and the air inlet channel (25) can introduce external gas into the reaction chamber (100); wherein the retaining ring (231) is provided with an arc-shaped guide surface (2313), wherein the arc-shaped guide surface (2313) is located between the reaction chamber (100) and the exhaust channel (40), and can guide the gas in the chamber (10) to the exhaust channel (40).

9. The wafer processing device according to claim 8, characterized in that: The exhaust structure (4) comprises a first channel wall (41) and a second channel wall (42); the first channel wall (41) is arranged around the outer periphery of the second channel wall (42) and is spaced apart from the second channel wall (42) to enclose the exhaust channel (40); the first channel wall (41) is arranged on a side of the retaining ring (231) away from the top plate (21) and is spaced apart from the retaining ring (231) to form a purge channel (50) communicating with the exhaust channel (40); Relative to the bottom wall (11) of the shell (1), the height of the purge channel (50) is lower than that of the reaction chamber.

10. The wafer processing device according to claim 9, characterized in that: The purge channel (50) has an inlet end (501) and an outlet end (502), wherein the outlet end (502) is located on the inner side of the first channel wall (41), and the inlet end (501) is located on the outer side of the first channel wall (41), and relative to the bottom wall (11), the inlet end (501) is not lower than the outlet end (502).

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