Plasma confinement structure and plasma processing equipment

Abstract

The utility model provides a plasma confinement structure and plasma processing equipment. In one embodiment, the plasma confinement structure comprises a first ring made of a silicon-based material and provided with a first gas channel; the second ring is connected to the downstream side of the first ring, a second gas channel is formed in the second ring, and the second gas channel is communicated with the first gas channel; and a ground ring connected to the downstream side of the second ring and grounding the first ring. In another embodiment, the plasma confinement structure comprises a silicon-based confinement ring, a gas channel is formed in the silicon-based confinement ring, and the two sides of the downstream side of the silicon-based confinement ring are grounded. The plasma confinement structure is used for solving the problems that according to an existing plasma confinement structure, the service life of parts is short, and a coating material is damaged and sputtered to a wafer to affect the process result.

Description

Technical Field

[0001] This utility model relates to the field of semiconductor equipment technology, and in particular to a plasma confinement structure and plasma processing equipment. Background Technology

[0002] In plasma processing equipment, the plasma confinement structure needs to achieve two functions: 1. To confine the plasma within a specific range to ensure plasma stability and reduce ion leakage that could damage the cavity; 2. To ensure sufficient gas conductivity while maintaining plasma confinement so that reaction products can be discharged in a timely manner.

[0003] Existing plasma confinement structures consist of two parts: a gas confinement ring and a grounding ring. Both are aluminum-based structures with coatings. To achieve plasma confinement capability, the gas confinement ring needs to maintain a certain capacitance to ground to form a plasma sheath layer on the structure surface, which consumes ions and electrons passing through the gas confinement ring. Therefore, the gas confinement ring needs to be combined with the grounding ring to achieve plasma confinement. Because of the plasma sheath layer on the surface of the gas confinement ring, etching will occur on the surface of the gas confinement ring, leading to coating damage. The damaged coating material will sputter onto the wafer, affecting the process results. Utility Model Content

[0004] The purpose of this invention is to provide a plasma confinement structure and plasma processing equipment to solve the problems of low component life, damage to coating materials and sputtering onto wafers that affect process results in existing plasma confinement structures.

[0005] To achieve the above objectives, this utility model is implemented through the following technical solution:

[0006] A plasma confinement structure, comprising:

[0007] The first ring is made of silicon-based material and has a first gas channel;

[0008] The second ring is connected to the downstream side of the first ring, and a second gas channel is formed in the second ring, which is connected to the first gas channel;

[0009] A grounding ring is connected to the downstream side of the second ring and grounds the first ring.

[0010] Optionally, the first ring has a plurality of slots extending through it along its axial direction to form the first gas passage; the second ring has a plurality of slots extending through it along its axial direction to form the second gas passage.

[0011] Optionally, the first ring includes a group of concentric first ring bodies arranged radially spaced apart and a plurality of first radial connectors, the annular channel formed between adjacent first ring bodies serves as the first gas channel, and the downstream side of the first ring body is fixedly connected to the plurality of first radial connectors.

[0012] The second ring includes a set of concentric second ring bodies arranged radially spaced apart and a plurality of second radial connectors. The annular channel formed between adjacent second ring bodies serves as the second gas channel. The downstream side of the second ring body is fixedly connected to the plurality of second radial connectors.

[0013] A first annular mounting portion is formed on the outer side of the first radial connector, and the first annular mounting portion is fixedly connected to the second radial connector.

[0014] Optionally, the first ring has a plurality of radially penetrating slots to form the first gas passage; the second ring has a plurality of radially penetrating slots to form the second gas passage.

[0015] Optionally, the first ring includes a set of concentric third ring bodies spaced apart along its axial direction and a plurality of first axial connectors, the annular channel formed between adjacent third ring bodies serves as the first gas channel, and the downstream side of the third ring body is fixedly connected to the plurality of first axial connectors.

[0016] The second ring includes a set of concentric fourth ring bodies spaced apart along its axial direction and a number of second axial connectors. The annular channel formed between adjacent fourth ring bodies serves as the second gas channel. The downstream side of the fourth ring body is fixedly connected to the number of second axial connectors.

[0017] A second annular mounting portion is formed at the top of the first axial connector, and the second annular mounting portion is fixedly connected to the second axial connector.

[0018] Optionally, a first gasket is provided between the second ring and the first ring, and a second gasket is provided between the second ring and the grounding ring. The first gasket and the second gasket are used for thermal and electrical conduction.

[0019] Optionally, the contact area between the second ring and the first and second gaskets is bare aluminum or anodized.

[0020] Optionally, the thickness of the anodic oxide layer is 50 micrometers to 100 micrometers.

[0021] Optionally, a third gasket is provided between the grounding ring and the grounding metal for heat and electrical conduction.

[0022] Optionally, the first and second gaskets are constructed as graphite-coated aluminum core gaskets, and the third gasket is constructed as a graphite-coated aluminum core gasket.

[0023] Optionally, the first ring is made of monocrystalline silicon, polycrystalline silicon, or silicon oxide.

[0024] Optionally, the second ring is made of a metal conductor.

[0025] Optionally, the surface of the second ring is provided with a corrosion-resistant coating.

[0026] A plasma confinement structure includes a silicon-based confinement ring, in which a gas channel is formed, and both sides of the downstream side of the silicon-based confinement ring are grounded.

[0027] Optionally, the silicon-based constraint ring has a plurality of slots extending along its axial direction to form the gas channel.

[0028] Optionally, the silicon-based confinement ring includes a set of concentric rings spaced radially apart and a plurality of radial connectors, with the annular channel formed between adjacent rings serving as the gas channel, and the downstream side of the rings being fixedly connected to the plurality of radial connectors.

[0029] Optionally, the silicon-based confinement ring has a plurality of slots extending radially through it to form the gas channel.

[0030] Optionally, the silicon-based constraint ring includes a set of concentric ring bodies spaced apart along its axial direction and a number of axial connectors. The annular channel formed between adjacent ring bodies serves as the gas channel, and the downstream side of the ring body is fixedly connected to the number of axial connectors.

[0031] Optionally, both sides of the downstream side of the silicon-based constraint ring are grounded using annular radio frequency gaskets.

[0032] Optionally, the silicon-based constraint ring is made of monocrystalline silicon, polycrystalline silicon, or silicon oxide.

[0033] A plasma processing device includes: a reaction chamber, a base for supporting a wafer disposed within the reaction chamber, a plasma region above the base, an exhaust region disposed below the reaction chamber, and a plasma confinement structure as described above disposed between the plasma region and the exhaust region.

[0034] Compared with the prior art, the present invention has the following advantages:

[0035] The first plasma confinement structure provided by this utility model divides the confinement ring into a first ring and a second ring located downstream of the first ring. The first ring, made of silicon-based material, faces the plasma region. Since silicon-based material has a certain plasma resistance and will vaporize when etched by plasma, even if the first ring is etched by plasma, it will not produce particles that contaminate the wafer. Furthermore, the first ring can protect the second ring from plasma etching, thereby improving the service life of the entire confinement ring.

[0036] The second plasma confinement structure provided by this invention integrates the confinement ring and the grounding ring into a single unit. The silicon-based confinement ring faces the plasma region. Because silicon has a certain degree of plasma resistance, the lifespan of the confinement ring is guaranteed. Furthermore, it vaporizes when etched by plasma, thus preventing particle contamination of the wafer even if the confinement ring is etched by plasma. In addition, the silicon-based confinement ring simultaneously achieves gas confinement and grounding functions, solving the problem of abnormal discharge caused by a voltage difference between the two components in existing confinement and grounding rings. Attached Figure Description

[0037] To more clearly illustrate the technical solution of this utility model, the drawings used in the description will be briefly introduced below. Obviously, the drawings in the following description are one embodiment of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort:

[0038] Figure 1 This is a schematic diagram of the structure of an existing plasma processing device;

[0039] Figure 2 This is a first structural diagram of the plasma confinement structure provided in Embodiment 1 of this utility model;

[0040] Figure 3 This is a second structural diagram of the plasma confinement structure provided in Embodiment 1 of this utility model;

[0041] Figure 4 This is a schematic diagram of another existing plasma processing device;

[0042] Figure 5 This is a third structural diagram of the plasma confinement structure provided in Embodiment 1 of this utility model;

[0043] Figure 6 This is a fourth structural diagram of the plasma confinement structure provided in Embodiment 1 of this utility model;

[0044] Figure 7 This is a first structural diagram of the plasma confinement structure provided in Embodiment 2 of this utility model;

[0045] Figure 8 This is a second structural diagram of the plasma confinement structure provided in Embodiment 2 of this utility model;

[0046] Figure 9 This is a third structural diagram of the plasma confinement structure provided in Embodiment 2 of this utility model;

[0047] Figure 10 This is a fourth structural diagram of the plasma confinement structure provided in Embodiment 2 of this utility model. Detailed Implementation

[0048] The following detailed description, in conjunction with the accompanying drawings and specific embodiments, further illustrates the proposed solution of this utility model. The advantages and features of this utility model will become clearer from the following description. It should be noted that the drawings are in a very simplified form and use non-precise proportions, intended only to facilitate and clearly illustrate the embodiments of this utility model. Please refer to the drawings to make the objectives, features, and advantages of this utility model more apparent and understandable. It should be understood that the structures, proportions, sizes, etc., depicted in the accompanying drawings are only for illustrative purposes to aid those skilled in the art and are not intended to limit the implementation conditions of this utility model. Therefore, they have no substantial technical significance. Any modifications to the structure, changes in proportions, or adjustments to the size, without affecting the effects and objectives achieved by this utility model, should still fall within the scope of the technical content disclosed in this utility model.

[0049] like Figure 1 The diagram shows a conventional plasma processing device, comprising a reaction chamber 1. The reaction chamber 1 contains a base 2 for supporting a wafer W and a spray head 3 for introducing reactive gas into the reaction chamber 1. The area between the spray head 3 and the base 2 is a plasma region. Typically, the spray head 3 serves as the upper electrode, and the base 2 as the lower electrode. High-frequency radio frequency power is applied to the upper and / or lower electrodes, generating a radio frequency electric field between them to dissociate the reactive gas into plasma. The plasma reaches the upper surface of the wafer W and performs etching and other processes on the wafer W. The plasma processing device has an exhaust region located at a suitable position at the bottom of the reaction chamber 1. This exhaust region is connected to an external exhaust pump to extract used reactive gas and byproduct gases from the reaction chamber 1 during the processing.

[0050] A plasma confinement structure is typically placed between the plasma region and the exhaust region, such as... Figure 1As shown, a constraint ring 101 is provided between the inner wall of the reaction chamber 1 and the outer periphery of the base 2. The constraint ring 101 is composed of multiple concentric rings. Different gas conductivity can be achieved by adjusting the depth, thickness, spacing and number of the rings. Below the constraint ring 101 is a grounding ring 102 composed of multiple rings, forming a grounding circuit. The grounding ring 102 has a small number of rings and a small depth.

[0051] As described in the background art, the existing confinement ring 101 is an aluminum-based structure with a coating. The upstream side of the confinement ring 101 faces the plasma region, where the plasma etches and damages the coating. Once the coating is damaged, the confinement ring 101 needs to be replaced. Furthermore, the damaged coating material is sputtered under the influence of the plasma, and the sputtered coating material falls onto the wafer W, thus affecting the process results. Based on this, the present invention provides a plasma confinement structure and a plasma processing device.

[0052] Example 1

[0053] Combination Figures 2-6 As shown, this embodiment provides a plasma confinement structure, including: a first ring 10, which is made of silicon and has a first gas channel 11 formed therein; a second ring 20, connected to the downstream side of the first ring 10, having a second gas channel 21 formed therein, which communicates with the first gas channel 11; and a grounding ring 30, connected to the downstream side of the second ring 20, grounding the first ring 10. It should be noted that the downstream side here is defined by the direction of gas discharge; that is, the side in which gas flows into the first ring 10 and the second ring 20 is the upstream side, and the side in which gas flows out is the downstream side.

[0054] In this embodiment, the constraint ring is divided into a first ring 10 facing the plasma region and a second ring 20 located downstream of the first ring. The first ring 10, made of silicon-based material, faces the plasma region. Since silicon-based material has a certain plasma resistance and will vaporize when etched by plasma, even if the first ring 10 is etched by plasma, it will not produce particle contamination of the wafer. Moreover, the first ring 10 can protect the second ring 20 from plasma etching, thereby improving the service life of the entire constraint ring.

[0055] Optionally, the first ring 10 is made of monocrystalline silicon, polycrystalline silicon, or silicon oxide. Different impedance levels of silicon-based materials can be selected based on the application scenario of the reaction chamber and actual process requirements. The second ring 20 is made of a metal conductor, such as aluminum. Furthermore, a corrosion-resistant coating can be provided on the surface of the second ring 20 to prevent direct contact between the plasma and the metal substrate of the second ring 20.

[0056] like Figure 2As shown, this is a first structure of the plasma confinement structure in this embodiment. The first ring 10 includes a set of concentric first ring bodies 12 spaced radially and a plurality of first radial connectors 13. The annular channel formed between adjacent first ring bodies 12 serves as the first gas channel 11. The downstream side of the first ring body 12 is fixedly connected to the plurality of first radial connectors 13, that is, the first radial connectors 13 connect first ring bodies 12 with different radii together. The second ring 20 includes a set of concentric second ring bodies 22 spaced radially and a plurality of second radial connectors 23. The annular channel formed between adjacent second ring bodies 22 serves as the second gas channel 21. The downstream side of the second ring body 22 is fixedly connected to the plurality of second radial connectors 23, that is, the second radial connectors 23 connect second ring bodies 22 with different radii together. To achieve the connection between the first ring 10 and the second ring 20, a first annular mounting portion 131 is formed on the outer side of the first radial connector 13, and the first annular mounting portion 131 is fixedly connected to the second radial connector 23. The terms "radial" and "axial" as used in this article refer to the centerline of the plasma confinement structure, which coincides with the centerline of the base 2 and also with the centerline of the cavity. "Radial" refers to the direction perpendicular to the centerline of the plasma confinement structure (perpendicular to the centerline of the cavity shown in the figure), and "axial" refers to the direction along the centerline of the plasma confinement structure (the same direction as the centerline of the cavity shown in the figure).

[0057] like Figure 2 As shown, a first gasket 40 is provided between the second ring 20 and the first ring 10 (specifically, it is provided between the first annular mounting part 131 and the second radial connector 23), and a second gasket 50 is provided between the second ring 20 and the grounding ring 30 (specifically, it is provided between the second radial connector 23 and the third radial connector 31 of the grounding ring 30). The first gasket 40 and the second gasket 50 are used for heat conduction and electrical conduction to ensure the stability of the capacitance to ground of the first ring 10 and the second ring 20.

[0058] Furthermore, to fine-tune the plasma confinement capability or plasma distribution required for different processes, different surface treatments can be applied to the connection surfaces between the second ring 20 and the first ring 10 and / or between the second ring 20 and the grounding ring 30 to achieve different ground capacitances. Specifically, the contact area between the second ring 20 and the first pad 40 can be bare aluminum or anodized, and / or the contact area between the second ring 20 and the second pad 50 can be bare aluminum or anodized. The thickness of the anodized layer can be 50 micrometers to 100 micrometers. Additionally, the material or thickness of the first pad 40 and the second pad 50 can be adjusted to regulate the ground capacitance. The first pad 40 and the second pad 50 can be constructed as graphite-coated aluminum core pads, or other pad structures capable of achieving grounding connection of the confinement rings can be used.

[0059] In this embodiment, a third gasket 60 (for example, disposed between the third radial connector 31 of the grounding ring 30 and the grounding metal) is provided between the grounding ring 30 and the grounding metal for heat and electricity conduction, so as to achieve zero potential and grounding effect of the grounding ring 30. The third gasket 60 can be constructed as a graphite-coated aluminum core gasket, or other gasket structures that can achieve grounding connection of the grounding ring can be used.

[0060] like Figure 3 As shown, this is a second structure of the plasma confinement structure in this embodiment. The first ring 10 has multiple slots extending along its axial direction to form the first gas channel 11; the second ring 20 has multiple slots extending along its axial direction to form the second gas channel 21. Since the first ring 10 is made of silicon, compared to metal materials, silicon is more difficult to process and more difficult to control in terms of precision. Therefore, compared to... Figure 3 As shown in the embodiment, the method of machining slots on the first ring 10 and the second ring 20 can reduce the machining difficulty and cost. The shape of the slots machined on the first ring 10 and the second ring 20 is not limited, and can be circular, oblong, etc. Figure 3 The diagram shows four slots machined from the inside out on the first ring 10 and the second ring 20 (the number and size of the slots are for illustrative purposes only; in actual applications, they need to be reasonably set to balance plasma confinement capability and gas conductivity). The slots machined on the first ring 10 and the second ring 20 are positioned correspondingly to avoid obstruction between the first gas channel 11 and the second gas channel 21, which would reduce the gas conductivity of the entire plasma confinement structure.

[0061] like Figure 3 As shown, with Figure 2Similar to the structure shown, a first gasket 40 (specifically, disposed between the outer edges of the second ring 20 and the first ring 10) is provided between the second ring 20 and the grounding ring 30, and a second gasket 50 (specifically, disposed between the outer edges of the second ring 20 and the grounding ring 30) is provided between the second ring 20 and the grounding ring 30. The first gasket 50 and the second gasket 60 are used for thermal and electrical conduction. The contact area between the second ring 20 and the first gasket 40 is bare aluminum or anodized, and / or the contact area between the second ring 20 and the second gasket 50 is bare aluminum or anodized. The thickness of the anodized layer can be 50 micrometers to 100 micrometers. Furthermore, the material or thickness of the first gasket 40 and the second gasket 50 can be adjusted to regulate the capacitance to ground. A third gasket 60 is provided between the grounding ring 30 and the grounding metal for thermal and electrical conduction. The first gasket 40 and the second gasket 50 can be constructed as graphite-coated aluminum core gaskets, and the third gasket 60 can be constructed as graphite-coated aluminum core gaskets, or other gasket structures that can achieve grounding connection can be used.

[0062] It should be noted that, Figure 2 , Figure 3 The plasma confinement structure shown is set in, as Figure 1 The base 2 inside the reaction chamber 1 shown is located between its outer perimeter and the chamber wall. In some other plasma processing devices, such as... Figure 4 As shown, the plasma confinement structure (including confinement ring 101 and grounding ring 102) is disposed between the upper edge of the base 2 and the spray head 3. Based on this, this embodiment also provides, for example... Figure 5 and Figure 6 The plasma confinement structure shown is suitable for, for example, Figure 4 In the plasma processing equipment shown.

[0063] like Figure 5As shown, this is a third structure of the plasma confinement structure in this embodiment. The first ring 10 includes a group of concentric third ring bodies 14 spaced apart along its axial direction and a plurality of first axial connectors 15. The annular channel formed between adjacent third ring bodies 14 serves as the first gas channel 11. The downstream side of each third ring body 14 is fixedly connected to a plurality of first axial connectors 14, that is, the first axial connectors 15 connect third ring bodies 14 of different heights together. The second ring 20 includes a group of concentric fourth ring bodies 24 spaced apart along its axial direction and a plurality of second axial connectors 25. The annular channel formed between adjacent fourth ring bodies 24 serves as the second gas channel 21. The downstream side of each fourth ring body 24 is fixedly connected to a plurality of second axial connectors 25, that is, the second axial connectors 25 connect fourth ring bodies 24 of different heights together. To achieve the connection between the first ring 10 and the second ring 20, a second annular mounting portion 151 is formed on the top of the first axial connector 15, and the second annular mounting portion 151 is fixedly connected to the second axial connector 25.

[0064] A first gasket 40 (specifically, disposed between the second annular mounting portion 151 and the second axial connector 25) is provided between the second ring 20 and the first ring 10, and a second gasket 50 (specifically, disposed between the second axial connector 25 and the third axial connector 32 of the grounding ring 30) is provided between the second ring 20 and the grounding ring 30. The first gasket 40 and the second gasket 50 are used for thermal and electrical conduction. The contact area between the second ring 20 and the first gasket 40 is bare aluminum or anodized, and / or the contact area between the second ring 20 and the second gasket 50 is bare aluminum or anodized. The thickness of the anodized layer can be 50 micrometers to 100 micrometers. In addition, the material or thickness of the first gasket 40 and the second gasket 50 can be adjusted to adjust the capacitance to ground. A third gasket 60 is provided between the grounding ring 30 and the grounding ground metal for thermal and electrical conduction to achieve zero potential and grounding effect of the grounding ring 30. The first gasket 40 and the second gasket 50 can be constructed as graphite-coated aluminum core gaskets, and the third gasket 60 can be constructed as graphite-coated aluminum core gaskets, or other gasket structures that can achieve grounding connection can be used.

[0065] like Figure 6 As shown, this is the fourth structure of the plasma confinement structure in this embodiment. The first ring 10 has a plurality of slots that penetrate radially to form the first gas channel 11; the second ring 20 has a plurality of slots that penetrate radially to form the second gas channel 21. Figure 6 The diagram schematically shows that the first ring 10 and the second ring 20 have four slots machined from top to bottom.

[0066] A first gasket 40 (specifically, positioned between the top edges of the second ring 20 and the first ring 10) is provided between the second ring 20 and the grounding ring 30, and a second gasket 50 (specifically, positioned between the top edges of the second ring 20 and the grounding ring 30) is provided between the second ring 20 and the grounding ring 30. The first gasket 40 and the second gasket 50 are used for thermal and electrical conductivity. The contact area between the second ring 20 and the first gasket 40 is bare aluminum or anodized, and / or the contact area between the second ring 20 and the second gasket 50 is bare aluminum or anodized. The thickness of the anodized layer can be 50 micrometers to 100 micrometers. Furthermore, the material or thickness of the first gasket 40 and the second gasket 50 can be adjusted to regulate the capacitance to ground. A third gasket 60 is provided between the grounding ring 30 and the grounding metal for thermal and electrical conductivity, thereby achieving zero potential and grounding effect for the grounding ring 30. The first gasket 40 and the second gasket 50 can be constructed as graphite-coated aluminum core gaskets, and the third gasket 60 can be constructed as graphite-coated aluminum core gaskets, or other gasket structures that can achieve grounding connection can be used.

[0067] By using a separate upstream and downstream confinement ring design, the upstream silicon-based confinement ring can act as a sacrificial component to absorb most of the bombardment from charged particles, while the downstream conductive confinement ring can enhance the grounding effect and absorb the remaining small amount of charged particles. Thus, even if the upstream silicon-based confinement ring is worn out, it will not produce particulate pollution and can be replaced at any time. The downstream conductive confinement ring is bombarded less, its lifespan is significantly extended, and the overall operating cost is lower.

[0068] Example 2

[0069] Combination Figures 7-10 As shown, this embodiment provides a plasma confinement structure, including: a silicon-based confinement ring 70, in which a gas channel 71 is formed, and both sides of the downstream side of the silicon-based confinement ring 70 are grounded.

[0070] In this embodiment, a silicon-based confinement ring 70 is used facing the plasma region. Since silicon-based material has a certain plasma resistance, the service life of the confinement ring is guaranteed. Moreover, it will vaporize when etched by plasma, so even if the confinement ring is etched by plasma, it will not cause particle contamination of the wafer.

[0071] Furthermore, since the existing plasma confinement structure includes a confinement ring 101 and a grounding ring 102 connected together (such as...), Figure 1 and Figure 4As shown, gas confinement and grounding are achieved through a single ring (e.g., a confinement ring 101 and a grounding ring 102). However, in practical applications, it is impossible to guarantee that the confinement ring 101 and the grounding ring 102 are in phase. During long-term use, abnormal discharge can occur between the confinement ring 101 and the grounding ring 102, leading to component damage and affecting process performance. This embodiment integrates the confinement ring 101 and the grounding ring 102 into a single unit, using a silicon-based confinement ring 70 to simultaneously achieve gas confinement and grounding functions. This solves the problem of abnormal discharge caused by a voltage difference between the two components, the confinement ring 101 and the grounding ring 102.

[0072] Optionally, the silicon-based confinement ring 70 is made of monocrystalline silicon, polycrystalline silicon, or silicon oxide. Different impedance levels of silicon-based materials can be used depending on the application scenario of the reaction chamber and the actual process requirements.

[0073] Similar to Embodiment 1, this embodiment provides four structures for plasma confinement structures.

[0074] like Figure 7 As shown, this is the first structure of the plasma confinement structure in this embodiment. The silicon-based confinement ring 70 includes a set of concentric rings 72 spaced radially apart and several radial connectors 73. The annular channel formed between adjacent rings 72 serves as the gas channel 71. The downstream side of each ring 72 is fixedly connected to several radial connectors 73, that is, the radial connectors 73 connect rings 72 of different radii together. To ensure grounding and plasma confinement effect, the inner and outer sides of the downstream side of the silicon-based confinement ring 70 are grounded using annular radio frequency washers 80. The annular radio frequency washers are standard parts and will not be described in detail here.

[0075] like Figure 8 As shown, this is the second structure of the plasma confinement structure in this embodiment. The silicon-based confinement ring 70 has multiple slots extending along its axial direction to form the gas channel 71. Since the silicon-based confinement ring 70 is made of silicon, compared to metal materials, silicon-based materials are more difficult to process and more difficult to control in terms of precision. Therefore, compared to... Figure 7 As shown in the embodiment, the method of machining slots on the silicon-based constraint ring 70 can reduce the machining difficulty and cost. The shape of the slots machined on the silicon-based constraint ring 70 is not limited and can be circular, oblong, etc. Figure 8 The slot is shown to be a radially oriented, waist-shaped hole. Both the inner and outer sides of the downstream side of the silicon-based confinement ring 70 are grounded using annular radio frequency gaskets 80 to ensure grounding and plasma confinement effectiveness.

[0076] like Figure 9As shown, this is the third structure of the plasma confinement structure in this embodiment. The silicon-based confinement ring 70 includes a group of concentric rings 72 spaced apart along its axial direction and several axial connectors 74. The annular channel formed between adjacent rings 72 serves as the gas channel 71. The downstream side of each ring 72 is fixedly connected to several of the axial connectors 74, that is, the axial connectors 74 connect rings 72 of different heights together. To ensure grounding and plasma confinement effect, the top and bottom sides of the downstream side of the silicon-based confinement ring 70 are grounded using annular radio frequency washers 80.

[0077] like Figure 10 As shown, this is the fourth structure of the plasma confinement structure in this embodiment. The silicon-based confinement ring 70 has a plurality of slots that extend radially through it to form the gas channel 71. Figure 10 The diagram schematically illustrates a waist-shaped slot along the axial direction. Both the top and bottom sides of the downstream side of the silicon-based confinement ring 70 are grounded using annular radio frequency gaskets 80 to ensure effective grounding and plasma confinement.

[0078] Based on the same inventive concept, this embodiment also provides a plasma processing device, including: a reaction chamber, a base for supporting a wafer disposed in the reaction chamber, a plasma region above the base, an exhaust region disposed at the lower part of the reaction chamber, and a plasma confinement structure as described in Embodiment 1 or Embodiment 2 disposed between the plasma region and the exhaust region.

[0079] It should be noted that, in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

[0080] Although the present invention has been described in detail through the above preferred embodiments, it should be understood that the above description should not be considered as a limitation of the present invention. Various modifications and substitutions to the present invention will be apparent to those skilled in the art after reading the above content. Therefore, the scope of protection of the present invention should be defined by the appended claims.

Claims

1. A plasma confinement structure, characterized in that, include: The first ring is made of silicon-based material and has a first gas channel; The second ring is connected to the downstream side of the first ring, and a second gas channel is formed in the second ring, which is connected to the first gas channel; A grounding ring is connected to the downstream side of the second ring and grounds the first ring.

2. The plasma confinement structure as described in claim 1, characterized in that, The first ring has multiple slots extending along its axial direction to form the first gas passage; the second ring has multiple slots extending along its axial direction to form the second gas passage.

3. The plasma confinement structure as described in claim 1, characterized in that, The first ring includes a set of concentric first ring bodies arranged radially spaced apart and a plurality of first radial connectors. The annular channel formed between adjacent first ring bodies serves as the first gas channel. The downstream side of the first ring body is fixedly connected to the plurality of first radial connectors. The second ring includes a set of concentric second ring bodies arranged radially spaced apart and a plurality of second radial connectors. The annular channel formed between adjacent second ring bodies serves as the second gas channel. The downstream side of the second ring body is fixedly connected to the plurality of second radial connectors. A first annular mounting portion is formed on the outer side of the first radial connector, and the first annular mounting portion is fixedly connected to the second radial connector.

4. The plasma confinement structure as described in claim 1, characterized in that, The first ring has a plurality of radially penetrating slots to form the first gas channel; the second ring has a plurality of radially penetrating slots to form the second gas channel.

5. The plasma confinement structure as described in claim 1, characterized in that, The first ring includes a set of concentric third ring bodies spaced apart along its axial direction and a plurality of first axial connectors. The annular channel formed between adjacent third ring bodies serves as the first gas channel. The downstream side of the third ring body is fixedly connected to the plurality of first axial connectors. The second ring includes a set of concentric fourth ring bodies spaced apart along its axial direction and a number of second axial connectors. The annular channel formed between adjacent fourth ring bodies serves as the second gas channel. The downstream side of the fourth ring body is fixedly connected to the number of second axial connectors. A second annular mounting portion is formed at the top of the first axial connector, and the second annular mounting portion is fixedly connected to the second axial connector.

6. The plasma confinement structure as described in claim 1, characterized in that, A first gasket is provided between the second ring and the first ring, and a second gasket is provided between the second ring and the grounding ring. The first gasket and the second gasket are used for thermal and electrical conduction.

7. The plasma confinement structure as described in claim 6, characterized in that, The contact area between the second ring and the first and second gaskets is bare aluminum or anodized.

8. The plasma confinement structure as described in claim 7, characterized in that, The thickness of the anodic oxide layer is 50 micrometers to 100 micrometers.

9. The plasma confinement structure as described in claim 1, characterized in that, A third gasket is provided between the grounding ring and the grounding metal for heat and electricity conduction.

10. The plasma confinement structure as described in claim 6, characterized in that, The first gasket and the second gasket are constructed as graphite-encapsulated aluminum core gaskets.

11. The plasma confinement structure as described in claim 9, characterized in that, The third gasket is constructed as a graphite-encapsulated aluminum core gasket.

12. The plasma confinement structure as described in claim 1, characterized in that, The first ring is made of monocrystalline silicon, polycrystalline silicon, or silicon oxide.

13. The plasma confinement structure as described in claim 1, characterized in that, The second ring is made of a metallic conductor.

14. The plasma confinement structure as described in claim 13, characterized in that, The surface of the second ring is provided with a corrosion-resistant coating.

15. A plasma confinement structure, characterized in that, include: A silicon-based confinement ring, wherein a gas channel is formed in the silicon-based confinement ring, and both sides of the downstream side of the silicon-based confinement ring are grounded.

16. The plasma confinement structure as described in claim 15, characterized in that, The silicon-based confinement ring has multiple slots that extend through it along its axial direction to form the gas channel.

17. The plasma confinement structure as described in claim 15, characterized in that, The silicon-based confinement ring includes a set of concentric rings spaced radially apart and several radial connectors. The annular channel formed between adjacent rings serves as the gas channel, and the downstream side of the ring is fixedly connected to several radial connectors.

18. The plasma confinement structure as described in claim 15, characterized in that, The silicon-based confinement ring has multiple slots that extend radially through it to form the gas channel.

19. The plasma confinement structure as described in claim 15, characterized in that, The silicon-based confinement ring includes a set of concentric rings spaced apart along its axial direction and several axial connectors. The annular channel formed between adjacent rings serves as the gas channel, and the downstream side of the ring is fixedly connected to several of the axial connectors.

20. The plasma confinement structure as described in claim 15, characterized in that, Both sides of the downstream side of the silicon-based constraint ring are grounded using annular radio frequency gaskets.

21. The plasma confinement structure as described in claim 15, characterized in that, The silicon-based constraint ring is made of monocrystalline silicon, polycrystalline silicon, or silicon oxide.

22. A plasma processing device, characterized in that, include: A reaction chamber is provided with a base for supporting a wafer. Above the base is a plasma region, and below the reaction chamber is an exhaust region. A plasma confinement structure as described in any one of claims 1 to 21 is provided between the plasma region and the exhaust region.

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