Semiconductor dry etching equipment

Abstract

The invention discloses semiconductor dry etching equipment, which comprises a reaction cavity; the fixed baffle is connected with one side of the reaction cavity; the sealing ring is of an annular structure and is arranged between the reaction cavity and the fixed baffle, so that sealing is formed between the reaction cavity and the fixed baffle; the anti-corrosion structure is of an annular structure, is arranged on the fixed baffle and extends into the reaction cavity, and corrosion of the sealing ring is slowed down by reducing the flowing speed of process gas and plasma at the anti-corrosion structure at any time. The service life of the sealing ring can be effectively prolonged, and the abnormal phenomenon of cavity leakage in the working process of the reaction cavity is reduced.

Description

Technical Field

[0001] The invention belongs to the technical field of semiconductor manufacturing process equipment, and in particular relates to semiconductor dry etching equipment. Background Art

[0002] The dry etching chamber in semiconductor wafer manufacturing equipment must maintain a high vacuum state during operation. The process gas is introduced and the RF power source dissociates the gas to form a plasma to etch the wafer. The dry etching process has very high requirements for the vacuum degree of the chamber, that is, the sealing of the chamber is very high, and a low leakage rate is required. If the leakage rate is too high, the gas in the air leaks into the chamber, which will have a great impact on the dry etching process, causing process deviation, process defects, and even the scrapping of the wafer in process.

[0003] In view of the above problems, it is an urgent problem to develop a semiconductor dry etching device to reduce the abnormal phenomenon of leakage in the cavity during operation.

[0004] It should be understood that the above statements merely provide background technology related to the present invention and do not necessarily constitute prior art. Summary of the invention

[0005] The purpose of the present invention is to provide a semiconductor dry etching device to increase the life of a sealing ring and reduce the abnormal phenomenon of cavity leakage in a reaction chamber during operation.

[0006] To achieve the above-mentioned purpose, the present invention provides a semiconductor dry etching device, comprising: a reaction chamber; a fixed baffle connected to one side of the reaction chamber; a sealing ring, which is an annular structure, arranged between the reaction chamber and the fixed baffle, so that a seal is formed between the reaction chamber and the fixed baffle; an anti-corrosion structure, which is an annular structure, arranged on the fixed baffle and extending to the interior of the reaction chamber, so as to slow down the corrosion of the sealing ring by reducing the instantaneous flow rate of process gas and plasma at the anti-corrosion structure.

[0007] Optionally, the reaction chamber includes: a chamber body; a chamber connector, which has a cavity therein, one end of which is fixedly connected to one side of the chamber body and communicates with the chamber body, and the other end of which is connected to the fixed baffle.

[0008] Optionally, the anti-corrosion structure extends along the axial direction of the cavity connector into the cavity of the cavity connector.

[0009] Optionally, the distance that the anti-corrosion structure extends to the inside of the cavity of the cavity connector is in the range of 1 cm to 1.5 cm.

[0010] Optionally, a gap is provided between the anti-corrosion structure and the inner wall of the cavity connector.

[0011] Optionally, the gap distance ranges from 3 mm to 5 mm.

[0012] Optionally, the fixed baffle and the anti-corrosion structure are integrally formed.

[0013] Optionally, the fixed baffle and the anti-corrosion structure are both made of aluminum alloy.

[0014] Optionally, the surface of the anti-corrosion structure is subjected to hard anodized coating treatment.

[0015] Optionally, the surface of the anti-corrosion structure is smoothed.

[0016] Optionally, the cross-section of the anti-corrosion structure is configured to be a long strip or a wavy shape.

[0017] Optionally, an observation window is provided on the fixed baffle to observe the interior of the reaction chamber.

[0018] Optionally, the observation window is made of quartz glass.

[0019] To sum up, compared with the prior art, the semiconductor dry etching equipment provided by the present invention increases the contact distance between the process gas and plasma and the sealing ring by introducing an anti-corrosion structure, thereby reducing the instantaneous flow rate of the process gas and plasma at the anti-corrosion structure, thereby effectively slowing down the corrosion of the sealing ring by the process gas and plasma, significantly extending the service life of the sealing ring, reducing the risk of cavity leakage, and ensuring the stability and consistency of the semiconductor wafer etching process, which has great practical value and broad application prospects. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 It is a structural schematic diagram of a semiconductor dry etching device in the prior art;

[0021] Figure 2 A schematic diagram of the structure of a semiconductor dry etching device with an anti-corrosion structure added after optimization of the present invention;

[0022] Figure 3 It is a schematic structural diagram of the semiconductor dry etching equipment which is optimized in the present invention and is provided with an observation window and an anti-corrosion structure. DETAILED DESCRIPTION

[0023] The following will be combined with the attached embodiment of the present invention Figure 1 ~Attached Figure 3 , the technical solutions, structural features, objectives achieved and effects in the embodiments of the present invention are described in detail.

[0024] It should be noted that the drawings are in a very simplified form and use non-precise proportions. They are only used to conveniently and clearly assist in explaining the embodiments of the present invention, and are not used to limit the conditions for the implementation of the present invention. Therefore, they have no substantive technical significance. Any structural modification, change in proportional relationship or adjustment of size, without affecting the effects and purposes that can be achieved by the present invention, should still fall within the scope of the technical content disclosed by the present invention.

[0025] It should be noted that, in the present invention, the terms "comprises", "includes" or any other variations thereof are intended to cover non-exclusive inclusion, so that a process, method, article or equipment including a series of elements includes not only the elements explicitly listed, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or equipment.

[0026] An existing semiconductor dry etching device, such as Figure 1 As shown, the reaction chamber 11 includes a chamber body 111 and a chamber connector 112, one end of the chamber connector 112 is fixedly connected to the chamber body 111, and the other end is connected to the fixed baffle 12. A sealing ring 13 is arranged between the chamber connector 112 and the fixed baffle 12, and the sealing ring 13 is an annular structure, so that a seal is formed between the reaction chamber 11 and the fixed baffle 12, thereby ensuring the leakage rate of the reaction chamber 11. An observation window 121 is arranged on the fixed baffle 12 to intuitively monitor the state in the reaction chamber 11 to ensure the accuracy and reliability of the semiconductor wafer etching process.

[0027] In this design, the wafer to be processed is placed inside the cavity body 111, and the process gas enters the reaction chamber 11 from one end of the cavity body 111. After being dissociated by the RF power supply, plasma is formed to etch the wafer. In the wafer etching process, ions and free radicals in the plasma play a key role. In the physical etching part, ions remove the excess oxide layer on the surface of the wafer through physical impact; in the chemical etching, free radicals react chemically with the surface material of the wafer to generate volatile byproducts, which are then detached from the surface of the wafer and extracted and discharged from the cavity body 111 by the vacuum pump.

[0028] It is understandable that in Figure 1As shown, the gas flows downward, and the process gas and plasma enter the cavity connector 112 from the cavity body 111 and contact the sealing ring 13, causing corrosion of the sealing ring 13. However, the contact distance between the process gas and plasma and the sealing ring 13 in the current semiconductor dry etching equipment is extremely short, and the sealing ring 13 is very susceptible to corrosion, causing cavity leakage. It is worth noting that the dry etching process has very high requirements for the vacuum degree of the cavity and requires a low leakage rate. If the leakage rate is too high, the gas in the air leaks into the cavity, which will have a great impact on the dry etching process, causing process deviation, process defects, and even the scrapping of wafers in process.

[0029] In order to solve the above problems, the present invention proposes a novel semiconductor dry etching device, which increases the contact distance between the process gas and plasma and the sealing ring 13 by adding an anti-corrosion structure to the existing semiconductor dry etching device, and is limited to the exchange within a narrow gap. As a result, the flow rate of the process gas and plasma at the anti-corrosion structure is reduced geometrically, thereby effectively slowing down the corrosion of the sealing ring by the process gas and plasma, significantly extending the service life of the sealing ring 13, and reducing the abnormal phenomenon of cavity leakage in the reaction chamber 11 during operation.

[0030] The technical solution of the semiconductor dry etching equipment of the present invention will be described in detail below in conjunction with the accompanying drawings and embodiments.

[0031] like Figure 2 As shown, a semiconductor dry etching device provided by the present invention includes: a reaction chamber 21; a fixed baffle 22, connected to one side of the reaction chamber 21; a sealing ring 23, which is an annular structure and has a sealing function, and is arranged between the reaction chamber 21 and the fixed baffle 22, so that a seal is formed between the reaction chamber 21 and the fixed baffle 22; an anti-corrosion structure 24, which is an annular structure, is arranged on the fixed baffle 22, and extends to the inside of the reaction chamber 21, and reduces the flow rate of process gas and plasma at the anti-corrosion structure 24 to slow down the corrosion of the sealing ring 23.

[0032] Furthermore, the reaction chamber 1 includes a chamber body 211 and a chamber connector 212 ; a cavity is provided inside the chamber connector 212 , one end of which is fixedly connected to one side of the chamber body 211 and communicated with the chamber body 211 , and the other end is connected to the fixed baffle 22 .

[0033] Furthermore, the anti-corrosion structure 24 extends along the axial direction of the cavity connector 212 to form an extension distance in the cavity of the cavity connector 212, and the extension distance ranges from 1 cm to 1.5 cm. In a preferred embodiment of the present invention, the cross section of the annular anti-corrosion structure 24 can be set to a long strip shape; it can be understood that when the cross section of the anti-corrosion structure 24 is set to a long strip shape, it is helpful to form a continuous protective layer on the surface of the annular structure of the anti-corrosion structure 24, thereby effectively preventing the occurrence of corrosion.

[0034] Furthermore, a gap is provided between the anti-corrosion structure 24 and the inner wall of the cavity connector 212, and the distance of the gap ranges from 3 mm to 5 mm.

[0035] Furthermore, the fixed baffle 22 and the anti-corrosion structure 24 are integrally formed, and both are made of aluminum alloy.

[0036] Compared with the prior art, in the embodiment of the present invention, the fixed baffle 22 is only composed of a single aluminum alloy plate, and no observation window is provided. The reason for this design is that with the development and maturity of semiconductor wafer manufacturing equipment technology, the possibility of abnormalities occurring during the transmission and handling of wafers in the equipment has been greatly reduced. Therefore, the necessity of checking the position of the wafer through the observation window is also reduced accordingly. In addition, the manpower, material and financial costs involved in the operation of replacing the observation window are not economical compared to the low probability demand of checking the position of the wafer. Based on the above considerations, existing dry etching equipment is usually no longer provided with an observation window.

[0037] Furthermore, in order to enhance the corrosion resistance of the anti-corrosion structure 24, its surface is treated with a hard anodized coating; it is understandable that this treatment method can significantly improve the corrosion resistance of the anti-corrosion structure 24, ensuring that it can maintain good performance and a long service life even in harsh environments.

[0038] Furthermore, the surface of the anti-corrosion structure 24 is smoothed; it is understandable that if the surface of the anti-corrosion structure 24 is a rough structure, it is easy to cause residues to accumulate on its surface during the etching process of the semiconductor wafer, while a smooth surface can effectively avoid the accumulation of residues.

[0039] It is worth noting that in the present invention, Figure 2As shown, the gas flows downward, and the process gas and plasma enter the cavity connector 212 from the cavity body 211. Therefore, if the semiconductor dry etching equipment is not provided with the anti-corrosion structure 24, the process gas and plasma will be frequently exchanged at the sealing ring 23. In this case, the contact distance between the sealing ring 23 and the process gas and plasma is extremely short, and it is very susceptible to corrosion. However, once the anti-corrosion structure 24 is introduced, the contact distance between the process gas and plasma and the sealing ring 23 will increase, and the exchange will be limited to a narrow gap. This causes the flow rate of the process gas and plasma at the anti-corrosion structure 24 to decrease geometrically, thereby effectively slowing down the corrosion of the sealing ring 23 by the process gas and plasma, significantly extending the service life of the sealing ring 23, and reducing the abnormal phenomenon of cavity leakage during operation of the reaction chamber 21.

[0040] like Figure 3 As shown, the semiconductor dry etching equipment provided by the present invention also includes an observation window 221 arranged on the fixed baffle 22 to observe the inside of the reaction chamber 21 to ensure the accuracy and reliability of the semiconductor wafer etching process; at the same time, through the observation window 221, the state inside the reaction chamber 21 can be intuitively monitored, including various changes in the etching process, thereby making the entire etching process more transparent and facilitating timely adjustment and optimization of process parameters.

[0041] Furthermore, in this embodiment, the observation window 221 is made of quartz glass.

[0042] It should be noted that, in the embodiment of the present invention, the main function of the observation window 221 is to check the physical position of the wafer through the observation window 211 when the physical position of the wafer in the cavity is abnormal.

[0043] To sum up, the semiconductor dry etching equipment provided by the present invention increases the contact distance between the process gas and plasma and the sealing ring by introducing an anti-corrosion structure, thereby reducing the instantaneous flow rate of the process gas and plasma at the anti-corrosion structure, thereby effectively slowing down the corrosion of the sealing ring by the process gas and plasma, significantly extending the service life of the sealing ring, reducing the risk of cavity leakage, and ensuring the stability and consistency of the semiconductor wafer etching process, and has great practical value and broad application prospects.

[0044] Although the content of the present invention has been described in detail through the above preferred embodiments, it should be appreciated that the above description should not be considered as a limitation of the present invention. After reading the above content, it will be apparent to those skilled in the art that various modifications and substitutions of the present invention will occur. Therefore, the protection scope of the present invention should be limited by the appended claims.

Claims

1. A semiconductor dry etching device, characterized in that: include: Reaction chamber; A fixed baffle connected to one side of the reaction chamber; A sealing ring, which is an annular structure, is disposed between the reaction chamber and the fixed baffle plate to form a seal between the reaction chamber and the fixed baffle plate; The anti-corrosion structure is an annular structure, which is arranged on the fixed baffle and extends into the reaction chamber. The corrosion of the sealing ring is slowed down by reducing the flow rate of process gas and plasma at the anti-corrosion structure.

2. The semiconductor dry etching equipment according to claim 1, characterized in that: The reaction chamber comprises: a chamber body; The cavity connector has a cavity therein, one end of which is fixedly connected to one side of the cavity body and communicated with the cavity body, and the other end of which is connected to the fixed baffle.

3. The semiconductor dry etching equipment according to claim 2, characterized in that: The anti-corrosion structure extends along the axial direction of the cavity connecting piece into the cavity of the cavity connecting piece.

4. The semiconductor dry etching equipment according to claim 3, characterized in that: The cross section of the anti-corrosion structure is arranged in a long strip shape.

5. The semiconductor dry etching equipment according to claim 3, characterized in that: The distance from the anti-corrosion structure extending to the inside of the cavity of the cavity connector is in the range of 1 cm to 1.5 cm.

6. The semiconductor dry etching equipment according to claim 5, characterized in that: A gap is arranged between the anti-corrosion structure and the inner wall of the cavity connecting piece.

7. The semiconductor dry etching equipment according to claim 6, characterized in that: The gap distance ranges from 3 mm to 5 mm.

8. The semiconductor dry etching equipment according to claim 1, characterized in that: The fixed baffle and the anti-corrosion structure are integrally formed.

9. The semiconductor dry etching equipment according to claim 8, characterized in that: The fixed baffle and the anti-corrosion structure are both made of aluminum alloy.

10. The semiconductor dry etching equipment according to claim 1, characterized in that: The surface of the anti-corrosion structure is subjected to hard anodized coating treatment.

11. The semiconductor dry etching equipment according to claim 1, characterized in that: The surface of the anti-corrosion structure is smoothed.

12. The semiconductor dry etching equipment according to claim 1, characterized in that: The fixed baffle is provided with an observation window for observing the interior of the reaction chamber.

13. The semiconductor dry etching equipment according to claim 12, characterized in that: The material of the observation window is quartz glass.

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