A plasma processing apparatus

Abstract

A plasma processing device includes: a reaction chamber main body, on the top of which a plasma channel plate assembly is provided; the plasma channel plate assembly includes: a plasma channel plate; a positioning member located on the side of the plasma channel plate, the elastic modulus of the positioning member being less than that of the plasma channel plate; a plasma generating unit located above the plasma channel plate. The plasma processing device can avoid damage to the plasma channel plate under high-temperature conditions.

Description

Technical Field

[0001] The present invention relates to the field of semiconductor manufacturing, and particularly to a plasma processing device. Background Art

[0002] In semiconductor manufacturing, there are multiple processes, and each process is completed by certain equipment and technology. Among them, plasma reactions are often used for chemical and physical deposition, etching, and photoresist ashing removal of semiconductor wafers and other substrates. Common plasma sources include ICP, CCP, and microwave generation methods. For the photoresist ashing removal process, it generally goes through the following processes: 1) Spin-coat the photoresist onto the semiconductor substrate; 2) Expose the photoresist layer to light for development in a targeted manner to form a specific photoresist pattern on the top of the semiconductor substrate, that is, part of the semiconductor substrate to be processed is exposed; 3) Etch or perform high-dose ion implantation on the exposed part of the semiconductor substrate; 4) Remove the photoresist that acts as a mask during the etching or high-dose ion implantation process, that is, the photoresist ashing removal process we mentioned. Typically, the photoresist ashing removal process includes two types: removing the photoresist mask after the etching process; removing the photoresist mask after the high-dose ion implantation process. For the photoresist ashing removal process, it is generally not desired that high-energy ions in the plasma directly act on the photoresist, but rather it is expected that a high-temperature chemical reaction occurs between the chemically active radical intermediates in the plasma and the photoresist.

[0003] Generally, the photoresist ashing reaction chamber consists of a plasma generation chamber and a wafer processing chamber; in order to prevent irreversible physical bombardment damage (Plasma Induced Damage) to the wafer by high-energy ions in the plasma during the photoresist ashing removal process, a plasma channel plate is usually installed between the plasma generation chamber and the wafer processing chamber: the plasma channel plate has a disk-shaped porous structure, and neutral chemical active groups can pass through freely, while charged ions are quenched after hitting the grid; the neutral chemical active groups passing through the plasma channel plate undergo a high-temperature chemical reaction with the wafer on the high-temperature wafer tray to remove the residual photoresist on the wafer surface.

[0004] However, the plasma channel plate in the prior art is prone to damage under high-temperature conditions. Summary of the Invention

[0005] The problem solved by the present invention is to provide a plasma processing device that can avoid damage to the plasma channel plate under high-temperature conditions.

[0006] To solve the above technical problems, the present invention provides a plasma processing device, comprising: a reaction chamber main body, a plasma channel plate assembly is provided at the top of the reaction chamber main body; the plasma channel plate assembly includes: a plasma channel plate; a positioning member located at the side of the plasma channel plate, the elastic modulus of the positioning member is less than the elastic modulus of the plasma channel plate; a plasma generating unit located above the plasma channel plate.

[0007] Optionally, the number of the positioning members is several, and the positioning members are evenly distributed along the periphery of the plasma channel plate.

[0008] Optionally, the material of the positioning member is a plastic material.

[0009] Optionally, the positioning member and the plasma channel plate are of an integral structure.

[0010] Optionally, the positioning member is a spring.

[0011] Optionally, the material of the spring is the same as the material of the plasma channel plate.

[0012] Optionally, the plasma channel plate assembly further includes: a support member, the support member is located at the bottom of the edge region of the plasma channel plate, and the support member is fixedly connected to the reaction chamber main body.

[0013] Optionally, the support member is of an annular structure.

[0014] Optionally, the reaction chamber main body has a top wall plate, and an opening penetrating the top wall plate is provided in the top wall plate; the plasma channel plate and the positioning member are embedded in the opening; the support member also extends below a part of the top wall plate; the plasma channel plate assembly further includes: a fastener, and the fastener fastens the support member to the top wall plate.

[0015] Optionally, it further includes: a wafer clamping platform located in the reaction chamber main body, the surface of the wafer clamping platform is adapted to place a wafer; the central axis of the plasma channel plate coincides with the central axis of the wafer clamping platform.

[0016] Compared with the prior art, the technical solution of the present invention has the following beneficial effects:

[0017] The plasma processing device provided by the technical solution of the present invention, the plasma channel plate assembly includes: a plasma channel plate; a positioning member located on the side of the plasma channel plate. Since the elastic modulus of the positioning member is less than the elastic modulus of the plasma channel plate, when the plasma channel plate expands under high temperature conditions, the plasma channel plate will extend outward and compress the positioning member, so that the stress of the plasma channel plate is released, thereby ensuring the good flatness of the plasma channel plate and avoiding damage to the plasma channel plate. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 is a schematic cross-sectional structure diagram of a plasma processing device;

[0019] Figure 2 is a schematic cross-sectional structure diagram of the plasma processing device in an embodiment of the present invention;

[0020] Figure 3 is a top view of the plasma channel plate assembly in an embodiment of the present invention;

[0021] Figure 4 is a top view of the plasma channel plate and the positioning member in another embodiment of the present invention. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0022] As described in the background art, the plasma channel plate in the prior art is prone to damage under high temperature conditions.

[0023] A typical structure is as Figure 1 shown, the plasma processing device includes: a wafer processing chamber 3; a wafer tray 1; a wafer 2; a plasma channel plate 4; a plasma channel plate fixing screw 5; a plasma generator 6; a plasma generation chamber 7; an air inlet 8; an air outlet 9.

[0024] The common material of the plasma channel plate 4 can be a conductive material, such as Al or Si, or an insulating material, such as ceramics, etc. Generally, the plasma channel plate 4 is fixed to the top wall of the cavity of the wafer processing chamber 3 by fixing screws and kept grounded (taking the Al material as an example). This installation and fixing method has the problem of stress release due to high-temperature thermal deformation of the plasma channel plate 4. Specifically, the high-density plasma of the plasma generator 6 continuously heats the plasma channel plate 4, and thermal deformation stress will be generated inside the plasma channel plate 4 due to high temperature. Usually, tensile stress appears on the top surface of the plasma channel plate 4, and compressive stress appears on the bottom surface of the plasma channel plate 4, resulting in the bending of the central plane of the plasma channel plate 4 towards the plasma generator 6. When the temperature of the plasma channel plate 4 is heated from 20°C to 200°C by the plasma, the radial expansion amount of the plasma channel plate 4 reaches about 2 mm; in order to release this expansion amount, the bending amount of the grid surface of the plasma channel plate 4 towards the plasma direction will reach 0.1 mm. During the cyclic expansion and contraction process of "low temperature - high temperature - low temperature - high temperature -...", small cracks and damages may occur at the center of the channel plate of the plasma channel plate 4, generating debris. This will further lead to the problem of particle contamination of the wafer.

[0025] In order to solve the above technical problems, the present invention provides a plasma processing device, including: a reaction chamber main body, a plasma channel plate assembly is arranged at the top of the reaction chamber main body; the plasma channel plate assembly includes: a plasma channel plate; a positioning member located at the side of the plasma channel plate, and the elastic modulus of the positioning member is less than the elastic modulus of the plasma channel plate; a plasma generating unit located above the plasma channel plate. The plasma processing device can avoid damage to the plasma channel plate under high-temperature conditions.

[0026] The embodiments of the present invention will be described in detail below with reference to the accompanying drawings.

[0027] An embodiment of the present invention provides a plasma processing device, with reference to Figure 2 and Figure 3 , including: a reaction chamber main body 200, a plasma channel plate assembly is arranged at the top of the reaction chamber main body 200; the plasma channel plate assembly includes: a plasma channel plate 210; a positioning member 211 located at the side of the plasma channel plate 210, and the elastic modulus of the positioning member 211 is less than the elastic modulus of the plasma channel plate 210; a plasma generating unit located above the plasma channel plate 210.

[0028] In this embodiment, the number of the positioning members 211 is several, and the positioning members 211 are evenly distributed along the periphery of the plasma channel plate 210.

[0029] In this embodiment, the material of the positioning member 211 is a plastic material, such as a spring-shaped component, Teflon, rubber, etc.

[0030] In this embodiment, the positioning member 211 is detachably separable from the plasma channel plate 210.

[0031] In a specific embodiment, the elastic modulus of the positioning member 211 is less than or equal to 1 GPa.

[0032] In this embodiment, the plasma channel plate assembly further includes: a support member 212, the support member 212 is located at the bottom of the edge region of the plasma channel plate 210, and the support member 212 is fixedly connected to the reaction chamber main body 200.

[0033] In this embodiment, the support member 212 is a ring structure, so that the support member 212 can better support the plasma channel plate 210, and the support forces received by various parts of the edge region of the plasma channel plate 210 are relatively consistent. In other embodiments, the number of the support members 212 is several, and several support members 212 are uniformly distributed around the bottom of the edge of the plasma channel plate 210.

[0034] The reaction chamber main body 200 has a top wall plate, and an opening penetrating the top wall plate is provided in the top wall plate; the plasma channel plate 210 and the positioning member 211 are embedded in the opening; the support member 212 also extends below a part of the top wall plate.

[0035] The plasma channel plate assembly further includes: a fastener 214, and the fastener 214 fastens the support member 212 to the top wall plate. The fastener 214 can be a screw, for example.

[0036] The plasma processing apparatus further includes: a wafer chucking platform 260 located in the reaction chamber main body 200, and the surface of the wafer chucking platform 260 is suitable for placing a wafer; the central axis of the plasma channel plate 210 coincides with the central axis of the wafer chucking platform 260.

[0037] In this embodiment, the material of the plasma channel plate 210 is a conductive material, such as Al or Si, or can also be an insulating material, such as ceramics, etc. The plasma channel plate 210 is a disk-shaped porous structure.

[0038] The plasma generating unit includes a reaction chamber dielectric tube 231 and a radio frequency antenna 232 located on the side wall of the reaction chamber dielectric tube 231. An air inlet 233 is provided at the top in the reaction chamber dielectric tube 231. The bottom of the reaction chamber main body 200 further has an air outlet 270.

[0039] The radio frequency antenna 232 excites the gas introduced into the dielectric tube 231 of the reaction chamber to generate plasma. The charged particles (including ions and electrons) in the plasma will be filtered out by the plasma channel plate 210. The charged ions are quenched after hitting the surface wall of the plasma channel plate 210. The neutral chemically active groups in the plasma will freely pass through the plasma channel plate 210 and enter the reaction chamber main body 200 to reach the surface of the wafer 10. The neutral chemically active groups passing through the plasma channel plate 210 react with the wafer 10 on the wafer clamping platform 260. Specifically, a high-temperature chemical reaction is carried out, for example, the residual photoresist on the surface of the wafer 10 can be removed.

[0040] In the plasma processing device of this embodiment, the plasma channel plate assembly includes: a plasma channel plate; a positioning member located on the side of the plasma channel plate. Since the elastic modulus of the positioning member is less than the elastic modulus of the plasma channel plate, when the plasma channel plate expands under high-temperature conditions, the plasma channel plate will extend outward and compress the positioning member, so that the stress of the plasma channel plate is released, thereby ensuring the good flatness of the plasma channel plate and avoiding damage to the plasma channel plate.

[0041] Another embodiment of the present invention also provides a plasma processing device. Please refer to Figure 4 , the difference between the plasma processing device in this embodiment and the previous embodiment is that: for the positioning member 211' located on the side of the plasma channel plate 210, the elastic modulus of the positioning member 211' is less than the elastic modulus of the plasma channel plate 210; the positioning member 211' is a spring.

[0042] In this embodiment, the number of the positioning members 211' is several, and the positioning members 211' are evenly distributed along the periphery of the plasma channel plate 210.

[0043] The elastic modulus of the aluminum plasma channel plate is at the level of 70 GPa. The elastic modulus of the spring is less than or equal to 1 GPa.

[0044] In this embodiment, the positioning member 211' and the plasma channel plate 210 are of an integral structure.

[0045] In this embodiment, the material of the spring is the same as the material of the plasma channel plate, so that there is a good bonding strength between the spring and the plasma channel plate, and at the same time, it is easy to install the plasma channel plate assembly.

[0046] In other embodiments, the material of the spring is different from the material of the plasma channel plate.

[0047] In this embodiment, the reaction chamber body 200 has a top wall plate, and the top wall plate has an opening penetrating through the top wall plate; the plasma channel plate 210 and the positioning member 211 are embedded in the opening; the support member 212 also extends below a part of the top wall plate; the support member 212 also extends below a part of the top wall plate; the plasma channel plate assembly further includes: a fastener 214, and the fastener 214 fastens the support member 212 to the top wall plate. The fastener 214 can be, for example, a screw.

[0048] The plasma processing apparatus further includes: a wafer chucking platform 260 located inside the reaction chamber body 200, and the surface of the wafer chucking platform 260 is adapted to place a wafer; the central axis of the plasma channel plate 210 coincides with the central axis of the wafer chucking platform 260.

[0049] Other components that are the same as those in the previous embodiment in this embodiment will not be described in detail.

[0050] Although the present invention is disclosed as above, the present invention is not limited thereto. Any person skilled in the art can make various changes and modifications without departing from the spirit and scope of the present invention. Therefore, the protection scope of the present invention should be subject to the scope defined by the claims.

Claims

1. A plasma processing device, characterized in that, Comprising: A reaction chamber main body, at the top of which a plasma channel plate assembly is provided; The plasma channel plate assembly includes: a plasma channel plate, the material of the plasma channel plate being a conductive material or an insulating material; a positioning member located at the side of the plasma channel plate, the elastic modulus of the positioning member being less than or equal to 1 GPa, and the elastic modulus of the positioning member being less than the elastic modulus of the plasma channel plate; A plasma generating unit located above the plasma channel plate; The positioning member and the plasma channel plate are of an integral structure; The number of the positioning members is several, and the positioning members are uniformly distributed along the periphery of the plasma channel plate; The plasma channel plate assembly further includes: a support member, the support member being located at the bottom of the edge region of the plasma channel plate, and the support member being fixedly connected to the reaction chamber main body; The reaction chamber main body has a top wall plate, and an opening penetrating the top wall plate is provided in the top wall plate; the plasma channel plate and the positioning member are embedded in the opening; the support member also extends below a part of the top wall plate; the plasma channel plate assembly further includes: a fastener for fastening the support member to the top wall plate.

2. The plasma processing device according to claim 1, characterized in that, The material of the positioning member is a plastic material.

3. The plasma processing device according to claim 1, characterized in that, The positioning member is a spring.

4. The plasma processing device according to claim 3, characterized in that, The material of the spring is the same as the material of the plasma channel plate.

5. The plasma processing device according to claim 1, characterized in that, The support member is of an annular structure.

6. The plasma processing device according to claim 1, characterized in that, Further comprising: A wafer clamping platform located inside the reaction chamber main body, the surface of the wafer clamping platform being adapted to place a wafer; the central axis of the plasma channel plate coincides with the central axis of the wafer clamping platform.

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