Plasma processing equipment, gas spray head, and method for manufacturing the same

Abstract

The present invention relates to a gas spray head and its manufacturing method, and a plasma processing device. The gas spray head (4) installed on the top of the vacuum reaction chamber (1) of the plasma processing device includes a spray head base (401) and a nozzle assembly (44) installed in a large-diameter through hole (402) in the spray head base (401). The spray head base (401) is manufactured by coating the surface of an aluminum material with yttrium oxide paint. By adding the nozzle assembly (44), the original fine hole in the spray head base (401) is changed into a large-diameter through hole (402) for mounting the nozzle assembly (44). After using the large-diameter through hole (402), it is easy to coat the inner surface of the large-diameter through hole (402) with anticorrosion paint, and the anticorrosion paint is uniformly distributed on the inner surface of the large-diameter through hole (402), and the anticorrosion paint is adhered to the inner surface of the large-diameter through hole (402).

Description

Technical Field

[0001] The present invention relates to the field of semiconductors, and particularly to plasma processing equipment, gas spray heads, and methods for manufacturing the same.

Background Art

[0002] Plasma processing equipment includes a reaction chamber. A gas spray head is installed as an upper electrode at the top of the reaction chamber, and a substrate holder is installed as a lower electrode inside the reaction chamber. The upper electrode and the lower electrode are connected to a high-frequency source to generate a radio frequency electromagnetic field between the upper electrode and the lower electrode. The reaction gas introduced into the reaction chamber by the gas spray head is ionized into plasma by the radio frequency electromagnetic field, and the plasma performs a processing process on the substrate installed on the substrate holder. In order to obtain a uniformly distributed gas, usually, a large number of fine holes are installed in the gas spray head. In addition, since the gas spray head, which is the upper electrode, needs to access high frequency, materials such as metal conductive materials or single crystal silicon and silicon carbide, which are semiconductor materials, are often used as the material of the gas spray head. However, gas spray heads made of single crystal silicon or silicon carbide are expensive. In order to reduce costs, currently, a process of generally processing micro holes using an aluminum-based matrix and then coating the aluminum-based matrix with yttrium oxide coating is adopted to manufacture the gas spray head. Such a gas spray head can significantly reduce the manufacturing cost of parts. However, it is difficult for the yttrium oxide coating to completely cover the inside of the micro holes of the gas spray head, and the bonding effect between the yttrium oxide coating in these micro holes and the aluminum-based matrix is very low. In the process of performing the plasma etching reaction, these yttrium oxide coating particles are likely to fall off from the micro holes, causing process contamination.

[0003] Note that what is described here only provides the background art related to the present invention and does not necessarily constitute the prior art.

Summary of the Invention

[0004] The present invention aims to provide plasma processing equipment, a gas spray head, and a manufacturing method thereof that uniformly distribute a corrosion-resistant coating on the surface of the spray head base, ensuring excellent processability without increasing costs, and also preventing the peeling of the corrosion-resistant coating and reducing process contamination.

[0005] To achieve the above objective, according to the present invention, A spray head base having multiple through holes, A gas spray head for use in plasma processing equipment is provided, comprising a plurality of nozzle assemblies including nozzles and plugs, wherein one nozzle assembly is housed in one of the through-holes, the nozzle is positioned in the through-hole and has a recess, the plug is positioned in the recess, and the bottom of the nozzle has a plurality of exhaust holes, and a gas passage communicating with the exhaust holes is formed between the nozzle and the plug.

[0006] The bottom surface of the nozzle is curved, the exhaust hole is installed on the curved surface, and the bottom shape of the plug matches the recess.

[0007] The materials of both the nozzle and the plug are ceramic materials.

[0008] The outer surface of the plug has at least one projection, and when the plug is placed in the recess, the projection abuts against the inner wall of the recess, and the gas passage is formed between the outer wall of the plug and the inner wall of the recess.

[0009] The nozzle uses yttrium oxide ceramics.

[0010] The plug is made of a solid ceramic material, and protrusions are provided on both the outer wall and the bottom of the plug. The gas passages are formed between the outer wall of the plug and the inner wall of the recess, and between the bottom of the plug and the bottom of the recess.

[0011] A connecting groove is provided in the inner wall of the recess, the number of the connecting grooves is the same as the number of protrusions provided on the outer wall of the plug, the position of the connecting groove corresponds to the protrusions provided on the outer wall of the plug, and the depth of the connecting groove is less than the protrusion height of the protrusions on the outer wall of the plug.

[0012] The connecting groove includes a through groove and a locking groove that communicate with each other, the through groove being closed at one end and extending to the top of the recess at the other end, both ends of the locking groove being closed ends, and the length of the locking groove matching the length of the projection installed on the outer wall of the plug.

[0013] The plug is made of a porous ceramic material, the protrusion is provided at the bottom of the plug, the gas passage is formed at the bottom of the plug and the bottom of the recess, the outer wall of the plug is in close contact with the inner wall of the recess, and the voids in the porous ceramic material communicate with the gas passage.

[0014] The exhaust holes are distributed symmetrically and uniformly on the bottom of the curved surface of the nozzle.

[0015] The inner diameter of the through hole is greater than 10 mm.

[0016] The spray head base is made of aluminum, and the surface of the aluminum material is coated with a corrosion-resistant coating.

[0017] The aforementioned corrosion-resistant coating material contains yttrium oxide.

[0018] The diameter of the exhaust port is 0.3 mm to 2 mm.

[0019] The outer diameter of the nozzle is equal to the inner diameter of the through hole.

[0020] The width of the gas passage is 0.1 mm to 0.3 mm.

[0021] A sealing ring is installed between the nozzle and the spray head base.

[0022] The present invention further provides a method for manufacturing the gas spray head, including the steps of processing a spray head base using an aluminum material, processing a plurality of through holes in the spray head base, and coating an yttrium oxide coating on all surfaces of the spray head base; processing a nozzle and a plug using a ceramic material, and combining the nozzle and the plug into a nozzle assembly; and installing each nozzle assembly into a through hole in the spray head base.

[0023] The present invention further provides a plasma processing apparatus including a vacuum reaction chamber in which a base for supporting a substrate is installed inside, and the gas spray head connected to a gas source by a mounting substrate is further installed inside.

[0024] The mounting substrate is connected to the spray head base, and a gap is formed between the mounting substrate and the plug. Both ends of the gap communicate with a gas source and a gas passage, respectively.

[0025] The plasma processing apparatus is a capacitively coupled plasma etching apparatus.

[0026] Compared with the prior art, the technical solution of the present invention has the following beneficial effects.

[0027] In the gas spray head and its manufacturing method provided by the present invention, the spray head base is manufactured by a method of coating / depositing yttrium oxide coating on the surface of an aluminum alloy. By adding a gas nozzle assembly and attaching it to the large-diameter through-hole of the spray head base, the characteristics of the micropores of the conventional gas spray head can be avoided. Using the spray head base with a large-diameter through-hole, an anticorrosive coating can be easily coated / deposited within its pore diameter, the anticorrosive coating can be uniformly distributed on the inner surface of the large-diameter through-hole, and the anticorrosive coating can be adhered to the inner surface of the large-diameter through-hole. Such a novel gas spray head not only guarantees excellent processability, but also avoids the problem that the anticorrosive coating in the micropores is likely to fall off, and can reduce process contamination.

Brief Description of the Drawings

[0028] [Figure 1] It is a schematic structural diagram of a capacitive coupling plasma etching device in one embodiment of the present invention. [Figure 2] It is a side cross-sectional view of the gas spray head in FIG. 1. [Figure 3] It is a plan view of the gas spray head in FIG. 2. [Figure 4] It is a bottom view of the gas spray head in FIG. 2. [Figure 5] It is a schematic structural diagram of the nozzle in FIG. 2. [Figure 6] It is a plan view of the gas spray head in one embodiment of the present invention. [Figure 7] It is a cross-sectional view of the C-C plane in FIG. 6. [Figure 8] It is a schematic structural diagram of the plug in FIG. 6. [Figure 9] It is a schematic structural diagram of the nozzle in FIG. 6. [Figure 10] It is a plan view of the gas spray head in another embodiment of the present invention. [Figure 11] It is a cross-sectional view of the D-D plane in FIG. 10. [Figure 12]Figure 10 is a schematic diagram of the plug's structure. [Modes for carrying out the invention]

[0029] Hereinafter, preferred embodiments of the present invention will be specifically described with reference to Figures 1 to 12.

[0030] As shown in Figure 1, the present invention provides a capacitively coupled plasma etching apparatus that includes a vacuum reaction chamber 1 in which a base 3 for supporting a substrate 2 is installed, and a gas spray head 4 connected to a gas source 6 by a mounting substrate 5 is further installed on top.

[0031] As shown in Figures 2 to 5, the gas spray head 4 includes a spray head base 401 connected to the mounting substrate 5. The spray head base 401 is made of aluminum and has a plurality of through holes 402, and the entire surface of the aluminum material of the spray head base 401 (including the inner surfaces of the through holes 402) is coated with a corrosion-resistant coating, such as yttrium oxide coating. The inner diameter of the through holes 402 is greater than 10 mm, making it easy to coat the inner surfaces of the through holes 402 with the corrosion-resistant coating. The corrosion-resistant coating is uniformly distributed on the inner surfaces of the through holes 402, ensuring close contact with the inner surfaces of the through holes 402 and avoiding contamination problems due to the peeling off of the corrosion-resistant coating. Each nozzle assembly 44 is housed in each of the through holes 402 in the spray head base 401. The nozzle assembly 44 includes a nozzle 403 and a plug 404 installed inside the nozzle 403. The nozzle 403 is positioned within the through-hole 402, the outer diameter of the nozzle 403 is equal to the inner diameter of the through-hole 402, and a rubber seal ring 408 is installed between the nozzle 403 and the spray head base 401. The rubber seal ring 408 ensures that the reaction gas does not leak out of the through-hole 402 and is instead ejected from the nozzle 403. The compressed rubber seal ring 408 can also press the nozzle 403, thereby fixing it to the spray base 401. The nozzle 403 has a recess 405, the plug 404 is positioned within the recess 405, a gas passage 407 is formed between the plug 404 and the nozzle 403, and the bottom of the nozzle 403 has a plurality of exhaust holes 406, the gas passage 407 is in communication with the exhaust holes 406. A gap 409 is formed between the plug 404 and the mounting substrate 5, and both ends of the gap 409 communicate with the gas source 6 and the gas passage 407, respectively, and the reaction gas from the gas source 6 is introduced into the gas passage 407 in the gas spray head through the gap 409. Finally, the reaction gas is released into the vacuum reaction chamber 1 through the exhaust port 406 which communicates with the gas passage 407.The bottom surface of the nozzle 403 is set up in an arc shape, the exhaust holes 406 are set up on the arc shape (see Figure 5), and the exhaust holes 406 are distributed symmetrically and uniformly on the bottom of the arc shape of the nozzle 403. By setting the exhaust holes 406 on the arc shape, the reaction gas released from the exhaust holes 405 can be further uniformly distributed around the circumference, improving the uniformity of the gas distribution in the vacuum reaction chamber. The diameter range of the exhaust holes 406 is 0.3 mm to 2 mm, preferably 0.5 mm. By making the exhaust holes 406 fine holes with a small diameter, the reaction gas ejected from the exhaust holes 406 can be controlled, and the uniformity of the reaction gas discharge can be guaranteed. The shape of the bottom of the plug 404 and the shape of the recess 405 inside the nozzle 403 match (correspond), thereby forming a gas passage 407 of uniform width between the plug 404 and the nozzle 403. If the gap between the plug 404 and the nozzle 403 is too large, a plasma arc is likely to occur, damaging the device structure. Therefore, it is necessary to control the width of the gas passage 407 formed between the plug 404 and the nozzle 403. The width of the gas passage 407 is usually set to 0.1 mm to 0.3 mm. Within this narrow width range, it is possible to avoid the generation of a plasma arc between the plug 404 and the nozzle 403. Both the nozzle 403 and the plug 404 are manufactured from ceramic material. The nozzle 403 is often made from yttrium oxide ceramic. The wall thickness of the nozzle 403 is generally processed to 1 mm to 5 mm. Nozzles 403 with such wall thicknesses are easy to process and, assuming sufficient rigidity, require less material than thinner nozzles 403, thus saving costs.

[0032] The present invention, by adding a nozzle assembly, changes the original micro-holes in the spray head base to large-diameter through-holes for attaching the nozzle assembly. After using the large-diameter through-holes, it is easier to coat the inner surface of the large-diameter through-holes with anti-corrosion coating, allowing the anti-corrosion coating to be uniformly distributed on the inner surface of the large-diameter through-holes, ensuring close contact between the anti-corrosion coating and the inner surface of the large-diameter through-holes, thereby preventing the anti-corrosion coating from peeling off inside the through-holes and reducing process contamination.

[0033] The plug 404 can be made of different ceramic materials depending on the requirements of the process environment. For example, a solid ceramic material may be used, or a porous ceramic material may be used, and the voids in the porous ceramic material itself may be used to form a gas passage.

[0034] As shown in Figures 6 to 9, in one embodiment of the present invention, the plug 404 is made of a solid ceramic material, such as aluminum oxide, yttrium oxide, or aluminum nitride, and any plasma corrosion-resistant material may be used to manufacture the plug 404. Protrusions 410 are provided on both the outer wall and the bottom of the plug 404. For example, two protrusions 410 may be symmetrically provided on the outer wall of the plug 404, or three protrusions 410 may be provided spaced apart from each other, or one protrusion 410 may be provided in the middle of the bottom of the plug. Accordingly, connecting grooves 411 are provided on the inner wall of the recess 405 of the nozzle 403, the number of connecting grooves 411 is the same as the number of protrusions 410 provided on the outer wall of the plug 404, and the position of the connecting grooves 411 corresponds to the protrusions 410 provided on the outer wall of the plug 404. The connecting grooves 411 include a through groove 411-1 and a locking groove 411-2 that communicate with each other. The through groove 411-1 is closed at one end and extends to the top of the recess 405 at the other end, and both ends of the locking groove 411-2 are closed ends, and the length of the locking groove 411-2 matches the length of the projection 410 installed on the outer wall of the plug 404. When the plug 404 is placed in the recess 405 of the nozzle 403, the projection 410 on the outer wall of the plug 404 slides from the through groove 411-1 in the inner wall of the recess 405 to the connecting groove 411, and then the plug 404 is rotated, engaging the projection 410 on the outer wall of the plug 404 with the locking groove 411-2, at which point the plug 404 and the nozzle 403 are securely connected. By making the protrusion height of the projection 410 on the outer wall of the plug 404 greater than the depth of the connection groove 411, the gas passage 407 can be formed between the outer wall of the plug 404 and the inner wall of the recess 405, and between the bottom of the plug 404 and the bottom of the recess 405. The projection 410 forms the gas passage 407 between the 404 plug and the nozzle 403, preventing the nozzle 403 and the plug 404 from coming into direct contact and causing localized blockage.

[0035] As shown in Figures 10 to 12, in another embodiment of the present invention, the plug 404 is made of a porous ceramic material, such as aluminum nitride, silicon carbide, or aluminum oxide. When the plug 404 is made of a porous ceramic material, the naturally occurring voids in the plug 404 can be used as internal gas passages. In this embodiment, the protrusion 410 installed on the outer wall of the plug 404 may be omitted, and the protrusion 410 may be installed only on the bottom of the plug 404. The naturally occurring internal gas passage in the plug 404 has one end communicating with the gap 409 between it and the mounting substrate 5, and the other end communicating with the gas passage 407 formed between the bottom of the plug 404 and the bottom of the recess 405. Accordingly, the outer wall of the plug 404 and the inner wall of the recess 405 can be installed in direct contact, thereby eliminating the need for the gas passage 407 formed between the outer wall of the plug 404 and the inner wall of the recess 405. This reduces the difficulty of processing the plug 404 and the processing time for the plug 404.

[0036] In the gas spray head provided by the present invention, the spray head base is still manufactured using a method that coats the surface of an aluminum material with yttrium oxide paint. By adding a nozzle assembly, the original micropores in the spray head base are changed to large-diameter through-holes for attaching the nozzle assembly. After using the large-diameter through-holes, it is easier to coat the inner surface of the large-diameter through-holes with anticorrosion paint, allowing the anticorrosion paint to be uniformly distributed on the inner surface of the large-diameter through-holes and to adhere closely to the inner surface of the large-diameter through-holes. Such a novel gas spray head not only guarantees excellent processability without increasing costs, but also avoids the detachment of the anticorrosion paint in the through-holes and reduces process contamination.

[0037] The present invention further provides a method for manufacturing a gas spray head. First, a spray head base is processed using an aluminum material. Subsequently, multiple through holes are machined into the spray head base, the inner diameter of which is greater than 10 mm. The larger hole diameter facilitates coating the inner surface of the through holes with anticorrosion paint. After all the through holes have been machined, yttrium oxide paint is applied to all surfaces of the spray head base, ensuring that the anticorrosion paint is uniformly distributed on the inner surface of the large-diameter through holes and adheres tightly to them. The spray head base and nozzle assembly can be manufactured simultaneously. Yttrium oxide ceramics are sintered and then machined to form nozzles and plugs. The plugs are then inserted into the nozzles and assembled into the nozzle assembly. Finally, each nozzle assembly is installed in the through holes of the spray head base, and a rubber seal ring is placed between the nozzle and the spray head base, thus completing the manufacturing of the entire gas spray head.

[0038] In the gas spray head and its manufacturing method provided in the present invention, the spray head base is manufactured by coating / depositing yttrium oxide paint onto the surface of an aluminum alloy. By adding a gas nozzle assembly and attaching it to the large-diameter through-hole of the spray head base, the characteristics of the micropores of conventional gas spray heads can be avoided. Using a spray head base with a large-diameter through-hole, the anticorrosive coating can be easily coated / deposited within the hole diameter, allowing the anticorrosive coating to be uniformly distributed on the inner surface of the large-diameter through-hole and to adhere closely to the inner surface of the large-diameter through-hole. Such a novel gas spray head not only guarantees excellent processability but also avoids the problem of the anticorrosive coating easily detaching from the micropores, thereby reducing process contamination.

[0039] In the embodiments of the present invention, the directions or positional relationships indicated by terms such as "center," "vertical direction," "horizontal direction," "length," "width," "thickness," "top," "bottom," "front," "back," "left," "right," "vertical," "horizontal," "top," "bottom," "inside," "outside," "clockwise," "counterclockwise," "axial direction," "radial direction," and "circumferential direction" are based on the directions or positional relationships shown in the drawings and are intended to facilitate the explanation of the embodiments. However, they do not indicate or suggest that such devices or elements have a specific direction or must be constructed and operated in a specific direction, and therefore should not be interpreted as steps that limit the present invention. Furthermore, the terms "first," "second," and "third" are used solely to explain the purpose and cannot be understood as steps that indicate or suggest relative importance.

[0040] In the present invention, unless otherwise specifically defined and limited, terms such as "attachment," "connection," "linking," and "fixing" should be understood in a broad sense. For example, a fixed connection may be a detachable connection, or it may be integrated, or it may be a mechanical connection, or an electrical connection, or a direct connection, or it may be an indirect connection via an intermediate medium, or it may be internal communication between two elements or an interaction relationship between two elements. Those skilled in the art will be able to understand the specific meaning of the above terms in the present invention depending on the specific situation.

[0041] While the scope of the present invention has been detailed in the preferred embodiments described above, it should be understood that it is not limited to the present invention. Those skilled in the art will see, after reading the above, that various modifications and substitutions to the present invention are possible. Therefore, the scope of protection of the present invention should be limited by the appended claims.

Claims

1. A spray head base having multiple through holes, Multiple nozzle assemblies including nozzles and plugs, The present invention includes a plurality of nozzle assemblies, each of which houses one nozzle assembly within one of the through-holes, the nozzle being positioned within the through-hole and having a recess, the plug being positioned within the recess, and a gas passage being formed between the nozzle and the plug. The nozzle comprises a cylindrical body and a bottom portion having a plurality of exhaust holes and provided at one end of the cylindrical body. A portion of the gas passage is formed between the inner circumferential wall of the cylindrical body and the outer circumferential wall of the plug. The other part of the gas passage is formed between the inner surface of the bottom and the bottom surface of the plug. A portion of the gas passage extends from one end of the cylindrical body to the other end of the cylindrical body, The other portion of the gas passage connects a part of the gas passage to the exhaust port. The reaction gas is supplied to the exhaust port from a portion of the gas passage through another portion of the gas passage. A gas spray head used in plasma processing equipment, characterized by the following features.

2. The bottom surface of the nozzle is curved, The exhaust port is installed on the curved surface, The gas spray head according to claim 1, characterized in that the bottom shape of the plug matches the recess.

3. The gas spray head according to claim 2, characterized in that the material of the nozzle and the plug are both ceramic materials.

4. The outer surface of the plug has at least one projection, The gas spray head according to claim 3, characterized in that when the plug is placed in the recess, the projection abuts against the inner circumferential wall of the recess.

5. The gas spray head according to claim 3, characterized in that the nozzle uses yttrium oxide ceramics.

6. The plug is made of a solid ceramic material. The outer wall and bottom of the aforementioned plug are both provided with protrusions. The gas spray head according to feature 4.

7. A connecting groove is provided on the inner circumferential wall of the aforementioned recess. The number of connection grooves is the same as the number of protrusions installed on the outer wall of the plug. The position of the connection groove corresponds to the projection installed on the outer wall of the plug. The gas spray head according to claim 6, characterized in that the depth of the connection groove is smaller than the protruding height of the protrusion on the outer wall of the plug.

8. The connecting groove includes through grooves and locking grooves that communicate with each other. The through groove is closed at one end and extends to the top of the recess at the other end. The gas spray head according to claim 7, characterized in that the locking groove has closed ends at both ends and its length matches the length of the protrusion installed on the outer wall of the plug.

9. The gas spray head according to claim 2, characterized in that the exhaust holes are distributed symmetrically and uniformly at the bottom of the arcuate surface of the nozzle.

10. The gas spray head according to claim 1, characterized in that the inner diameter of the through hole is greater than 10 mm.

11. The gas spray head according to claim 1, characterized in that the spray head base is made of aluminum material and the surface of the aluminum material is coated with a corrosion-resistant coating.

12. The gas spray head according to claim 11, characterized in that the corrosion-resistant coating material contains yttrium oxide.

13. The gas spray head according to claim 1, characterized in that the diameter of the exhaust port is 0.3 mm to 2 mm.

14. The gas spray head according to claim 1, characterized in that the outer diameter of the nozzle is equal to the inner diameter of the through hole.

15. The gas spray head according to claim 1, characterized in that the width of the gas passage is 0.1 mm to 0.3 mm.

16. The gas spray head according to claim 1, characterized in that a sealing ring is installed between the nozzle and the spray head base.

17. The steps include: processing a spray head base using aluminum material, machining multiple through holes in the spray head base, and coating all surfaces of the spray head base with yttrium oxide paint; The steps include: processing a nozzle and a plug using a ceramic material, and combining the nozzle and the plug into a nozzle assembly; A method for manufacturing a gas spray head according to any one of claims 1 to 16, comprising the step of installing each nozzle assembly into a through hole in the spray head base.

18. A plasma processing apparatus comprising a vacuum reaction chamber, wherein a gas spray head according to any one of claims 1 to 16 is installed, the gas spray head having a base for supporting a substrate installed inside and further connected to a gas source by a mounting substrate installed inside.

19. The mounting board is connected to the spray head base, and a gap is formed between the mounting board and the plug. The plasma processing apparatus according to claim 18, characterized in that both ends of the gap communicate with a gas source and a gas passage, respectively.

20. The plasma processing equipment according to claim 18, characterized in that the plasma processing equipment is a capacitively coupled plasma etching equipment.

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