Focusing ring structure and plasma equipment

Abstract

The utility model discloses a focusing ring structure and plasma equipment, and the focusing ring structure applied to the plasma equipment comprises a first focusing ring which is fixedly arranged on a pedestal; the second focusing ring comprises a main body part located at the top of the first focusing ring and extension parts which protrude out of the bottom surface of the main body and are located on the two sides of the first focusing ring, a groove is defined by the extension parts and the main body part, and the groove at least accommodates part of the first focusing ring within the preset travel range of height adjustment; and the lifting assembly is arranged at the bottom of the second focusing ring and is used for adjusting the distance between the bottom surface of the main body part and the top surface of the first focusing ring within a preset travel range of height adjustment. In the process of adjusting the distance between the bottom surface of the main body part and the top surface of the first focusing ring, the side wall of the extension part always has a contact part with the side wall of the first focusing ring, so that charges on the second focusing ring can be conducted to the base through the first focusing ring, and potential difference is not easy to form between the second focusing ring and the base; and the probability of arc discharge caused by potential difference is reduced.

Description

Technical Field

[0001] This utility model relates to the field of semiconductor manufacturing, and more particularly to a focusing ring structure and a plasma device. Background Technology

[0002] In the plasma processing of semiconductor integrated circuit manufacturing, in order to improve the edge effect of the wafer and make the uniformity of the central and edge regions of the wafer better after the process, a focusing ring is usually configured on the outer periphery of the wafer to be processed and the wafer stage.

[0003] However, the current structure of the focusing ring still needs improvement. Utility Model Content

[0004] The problem addressed by this invention is to provide a focusing ring structure and a plasma device to improve the focusing ring structure.

[0005] To address the aforementioned problems, this utility model provides a focusing ring structure applied to a plasma device, comprising: a first focusing ring for fixedly mounted on the base of the plasma device; a second focusing ring including a main body portion located at the top of the first focusing ring and extension portions protruding from the bottom surface of the main body portion and located on both sides of the first focusing ring, the extension portions and the main body portion forming a groove, wherein within a preset travel range for height adjustment, the groove accommodates at least a portion of the first focusing ring, such that the sidewall of the groove contacts the sidewall of the first focusing ring; and a lifting assembly disposed at the bottom of the second focusing ring, the lifting assembly being used to adjust the distance between the bottom surface of the main body portion and the top surface of the first focusing ring within the preset travel range for height adjustment.

[0006] Optionally, the plasma device further includes a stage located on the base for supporting a wafer; along the radial direction of the second focusing ring, the main body includes an outer ring portion on one side of the outer circumference and an inner ring portion on one side of the inner circumference, the top surface of the inner ring portion being lower than the top surface of the outer ring portion, the sidewall of the outer ring portion being connected to the top of the inner ring portion, the inner ring portion being disposed below the wafer and surrounding the stage, and the outer ring portion being surrounding the wafer; the extension portions protrude from the bottom surface of the outer ring portion and the bottom surface of the inner ring portion, respectively.

[0007] Optionally, the angle between the inner sidewall of the outer ring and the top surface of the inner ring is an obtuse angle.

[0008] Optionally, the lifting assembly includes: a push pin disposed at the bottom of the second focusing ring and abutting against the second focusing ring; and a transmission component fixedly connected to the bottom of the push pin, the transmission component being used to drive the push pin to move up and down in the vertical direction.

[0009] Optionally, the number of pins in the same lifting assembly can be multiple; the transmission component includes: a support component, which is fixedly connected to the bottom of the pins in the same lifting assembly; and a lifting column, which is fixedly disposed at the bottom of the support component.

[0010] Optionally, the same lifting assembly has two pins, one of which is a first pin located on the inner side of the first focusing ring, and the other is a second pin located on the outer side of the first focusing ring; along the radial direction of the first focusing ring, the first pin and the second pin of the same lifting assembly are symmetrically arranged on both sides of the first focusing ring.

[0011] Optionally, in a direction parallel to the top surface of the lifting column, the distance from the lifting column to the first ejector pin is equal to the distance from the lifting column to the second ejector pin.

[0012] Optionally, the ejector pin is disposed at the bottom of the extension and abuts against the extension.

[0013] Optionally, the height of the extension is less than or equal to the height of the first focusing ring, and the preset travel range of the height adjustment is less than the height of the extension.

[0014] Optionally, the number of lifting components is multiple, and the multiple lifting components are evenly arranged around the center of the first focusing ring.

[0015] Optionally, the number of lifting components is at least three.

[0016] Optionally, the first focusing ring may be a silicon carbide ring, a quartz ring, an alumina ceramic ring, or a silicon carbide ceramic ring; the second focusing ring may be a silicon carbide ring, a quartz ring, an alumina ceramic ring, or a silicon carbide ceramic ring.

[0017] Optionally, the first focusing ring and the second focusing ring are made of the same material.

[0018] Optionally, the focusing ring structure is applied to a plasma etching apparatus.

[0019] Accordingly, this utility model embodiment also provides a plasma device, including: a chamber; a base located in the chamber, the base having a stage for supporting a wafer; and a focusing ring structure as described in any embodiment of this utility model, the focusing ring structure being disposed on the base and surrounding the stage.

[0020] Optionally, the lifting assembly includes: a push pin that penetrates the base in the vertical direction and is slidably disposed in the base, and the push pin abuts against the bottom of the second focusing ring; a transmission component located on the side of the base opposite to the focusing ring structure, the transmission component being fixedly connected to the bottom of the push pin, and the transmission component being used to drive the push pin to move up and down in the vertical direction.

[0021] Optionally, the ejector pin is disposed at the bottom of the extension and abuts against the extension, and the difference between the height of the ejector pin and the height of the base is less than the height of the first focusing ring.

[0022] Compared with the prior art, the technical solution of this utility model embodiment has the following advantages:

[0023] The focusing ring structure provided in this embodiment includes a first focusing ring and a second focusing ring for fixedly mounted on the base of the plasma device. The second focusing ring includes a main body portion located at the top of the first focusing ring and extension portions protruding from the bottom surface of the main body portion and located on both sides of the first focusing ring. The extension portions and the main body portion form a groove. Within a preset travel range for height adjustment, the groove accommodates at least a portion of the first focusing ring so that the sidewall of the groove contacts the sidewall of the first focusing ring. A lifting assembly is disposed at the bottom of the second focusing ring. The lifting assembly is used to adjust the distance between the bottom surface of the main body portion and the top surface of the first focusing ring within the preset travel range for height adjustment. In this embodiment, during the adjustment of the distance between the bottom surface of the main body and the top surface of the first focusing ring, the sidewall of the extension portion and the sidewall of the first focusing ring are always in contact. The first focusing ring is fixedly mounted on the base of the plasma equipment, so that the charge on the second focusing ring can be conducted to the base through the first focusing ring. Consequently, during the plasma processing, the charge is less likely to accumulate on the second focusing ring, that is, a potential difference is less likely to form between the second focusing ring and the base, thereby reducing the probability of arc discharge caused by potential difference, and further reducing the probability of damage to the wafer to be processed, and also improving the process stability of plasma processing. Attached Figure Description

[0024] Figure 1 This is a schematic diagram of a focusing ring structure, a wafer, and a substrate.

[0025] Figure 2 This is a schematic diagram of a focusing ring structure at the end of a maintenance cycle.

[0026] Figure 3 This is a schematic diagram of another focusing ring structure, wafer, and substrate;

[0027] Figure 4 This is a top view of the focusing ring structure according to an embodiment of the present invention;

[0028] Figure 5 This is a schematic cross-sectional view of the focusing ring structure, wafer, and base according to an embodiment of the present invention.

[0029] Figure 6 yes Figure 5 A cross-sectional view of the structure after the second focusing ring of a certain height has been consumed;

[0030] Figure 7 yes Figure 6 A cross-sectional view of the structure after adjusting the distance between the bottom surface of the main body and the top surface of the first focusing ring;

[0031] Figure 8 This is a schematic diagram of the structure of the second focusing ring according to an embodiment of the present invention;

[0032] Figure 9 At the beginning of the maintenance cycle, under the action of the focusing ring structure in this embodiment of the invention, the etching rate of each region of the wafer is [not specified].

[0033] Figure 10 It is the end of the maintenance cycle. Under the action of the focusing ring structure in this embodiment of the invention, the etching rate of each region of the wafer is reduced. Detailed Implementation

[0034] Currently, the performance of focusing ring structures still needs improvement. This paper analyzes the reasons why the performance of focusing ring structures needs further improvement, using one such structure as an example. Figure 1 This is a schematic diagram of a focusing ring structure. Figure 2 This is a schematic diagram of a focusing ring structure at the end of a maintenance cycle.

[0035] refer to Figure 1 and Figure 2 A focusing ring structure, applied to a plasma device, includes: a focusing ring 10, for being disposed on the base 12 of the plasma device.

[0036] The focusing ring 10 is used to provide a uniform plasma during plasma processing. However, studies have found that within a maintenance cycle, the focusing ring 10 is continuously consumed by plasma bombardment, and its height gradually decreases. As the focusing ring 10 at the edge of wafer 11 is gradually consumed, the morphology of the plasma sheath 13 at the edge of wafer 11 changes (refer to reference). Figure 1 and Figure 2 This causes the plasma's motion direction to be distorted and deflected to a certain extent (e.g., Figure 2(As indicated by the middle arrow), this leads to wafer edge effects, such as uneven etching during plasma etching.

[0037] To address the edge effect in wafers, an alternative focusing ring structure is proposed. Figure 3 This is a schematic diagram of another focusing ring structure.

[0038] refer to Figure 3 A focusing ring structure, applied to a plasma device, includes: a focusing ring 20, for being disposed on the base of the plasma device, wherein the distance between the bottom surface of the focusing ring 20 and the base is adjustable so that the top surface of the focusing ring 20 is kept within a preset height range.

[0039] The top surface of the focusing ring 20 is kept within a preset height range, making it less likely for the plasma movement direction to be distorted or deflected. However, when the distance between the bottom surface of the focusing ring 20 and the base is adjusted, a gap 23 is formed between the focusing ring 20 and the base 22. During plasma processing, plasma accumulates on the focusing ring 20, causing a potential difference to form between the focusing ring 20 and the base 22 below it. This potential difference accumulated by the parallel plate capacitor structure can easily lead to arc discharge, thereby damaging the wafer 21.

[0040] To address the aforementioned technical problems, this utility model provides a focusing ring structure applied to a plasma device, comprising: a first focusing ring for fixedly mounted on a base of the plasma device; a second focusing ring including a main body portion located at the top of the first focusing ring and extension portions protruding from the bottom surface of the main body portion and located on both sides of the first focusing ring, the extension portions and the main body portion forming a groove, wherein within a preset travel range for height adjustment, the groove accommodates at least a portion of the first focusing ring, such that the sidewall of the groove contacts the sidewall of the first focusing ring; and a lifting assembly disposed at the bottom of the second focusing ring, the lifting assembly being used to adjust the distance between the bottom surface of the main body portion and the top surface of the first focusing ring within the preset travel range for height adjustment.

[0041] The solution disclosed in this embodiment includes a first focusing ring and a second focusing ring for fixedly mounted on the base of the plasma device. The second focusing ring includes a main body portion located at the top of the first focusing ring and extension portions protruding from the bottom surface of the main body portion and located on both sides of the first focusing ring. The extension portions and the main body portion form a groove. Within a preset travel range for height adjustment, the groove accommodates at least a portion of the first focusing ring so that the sidewall of the groove contacts the sidewall of the first focusing ring. A lifting assembly is disposed at the bottom of the second focusing ring. The lifting assembly is used to adjust the distance between the bottom surface of the main body portion and the top surface of the first focusing ring within the preset travel range for height adjustment. In this embodiment, during the adjustment of the distance between the bottom surface of the main body and the top surface of the first focusing ring, the sidewall of the extension portion and the sidewall of the first focusing ring are always in contact. The first focusing ring is fixedly mounted on the base of the plasma equipment, so that the charge on the second focusing ring can be conducted to the base through the first focusing ring. Consequently, during the plasma processing, the charge is less likely to accumulate on the second focusing ring, that is, a potential difference is less likely to form between the second focusing ring and the base, thereby reducing the probability of arc discharge caused by potential difference, and further reducing the probability of damage to the wafer to be processed, and also improving the process stability of plasma processing.

[0042] To make the above-mentioned objectives, features and advantages of the present invention more apparent and understandable, the specific embodiments of the present invention will be described in detail below with reference to the accompanying drawings.

[0043] Figure 4 This is a top view schematic diagram of the focusing ring structure according to an embodiment of the present invention. Figure 5 This is a schematic cross-sectional view of the focusing ring structure, wafer, and base according to an embodiment of the present invention. Figure 6 yes Figure 5 A cross-sectional view of the structure after consuming a certain height of the second focusing ring. Figure 7 yes Figure 6 A cross-sectional view of the structure after adjusting the distance between the bottom surface of the main body and the top surface of the first focusing ring. Figure 8 This is a schematic diagram of the structure of the second focusing ring in an embodiment of the present invention.

[0044] refer to Figures 4 to 8In this embodiment, the focusing ring structure, applied to a plasma device, includes: a first focusing ring 110, for fixedly mounted on the base 210 of the plasma device; and a second focusing ring 120, including a main body 121 located at the top of the first focusing ring 110, and extensions 122 protruding from the bottom surface of the main body 121 and located on both sides of the first focusing ring 110, the extensions 122 and the main body 121 forming a groove 1201 (e.g., Figure 8 As shown), within a preset travel range for height adjustment, the groove 1201 at least accommodates a portion of the first focusing ring 110, such that the sidewall of the groove 1201 contacts the sidewall of the first focusing ring 110; a lifting assembly 130 is disposed at the bottom of the second focusing ring 120, and the lifting assembly 130 is used to adjust the distance W between the bottom surface of the main body 121 and the top surface of the first focusing ring 110 within the preset travel range for height adjustment (e.g., ...). Figure 7 (As shown).

[0045] As an example, the focusing ring structure is applied to a plasma etching apparatus.

[0046] The plasma etching apparatus is used to remove material using plasma. In other embodiments, the focusing ring structure can also be applied to other suitable plasma apparatuses.

[0047] In this embodiment, the plasma device further includes a stage 220 located on the base 210, the stage 220 being used to support the wafer 200, thereby providing a process basis for plasma processing of the wafer 200.

[0048] The first focusing ring 110 is disposed on the base 210 of the plasma device to provide a process basis for conducting the charge on the second focusing ring 120 to the base 210 of the plasma device.

[0049] In this embodiment, the first focusing ring 110 includes a silicon carbide ring, a quartz ring, an alumina ceramic ring, or a silicon carbide ceramic ring.

[0050] Silicon carbide, quartz, alumina, and silicon carbide ceramics are commonly used materials for aggregated rings, which helps reduce process costs.

[0051] In other embodiments, the material of the first focusing ring may also be other materials that are resistant to plasma corrosion and have good thermal conductivity and thermal stability.

[0052] The second focusing ring 120 is used to provide uniform plasma to improve the edge effect of the wafer 200, and to always have a portion in contact with the sidewall of the first focusing ring 110 within a preset travel range of height adjustment, thereby conducting the charge on the main body 121 to the base 210 through the extension 122 and the first focusing ring 110.

[0053] Furthermore, the second focusing ring 120 covers the top and sidewalls of the first focusing ring 110, so that the consumption of the first focusing ring 110 under plasma bombardment is less than that of the second focusing ring 120 under plasma bombardment. This results in the replacement frequency of the first focusing ring 110 being less than that of the second focusing ring 120, which in turn helps to save process costs.

[0054] Specifically, the main body 121 is used to provide uniform plasma, and the extension 122 is used to always have a portion in contact with the sidewall of the first focusing ring 110 within a preset travel range of height adjustment.

[0055] In this embodiment, along the radial direction of the second focusing ring 120, the main body 121 includes an outer ring portion 123 located on the outer periphery and an inner ring portion 124 located on the inner periphery. The top surface height of the inner ring portion 124 is lower than the top surface height of the outer ring portion 123. The sidewall of the outer ring portion 123 is connected to the top of the inner ring portion 124. The inner ring portion 124 is used to be disposed below the wafer 200 and surround the stage 220, and the outer ring portion 123 is used to surround the wafer 200. The extension portion 122 protrudes from the bottom surface of the outer ring portion 123 and the bottom surface of the inner ring portion 124, respectively.

[0056] The outer ring portion 123 is used to surround the wafer 200, and the inner ring portion 124 is used to be disposed below the wafer 200 and surround the stage 220. The top surface height of the inner ring portion 124 is lower than the top surface height of the outer ring portion 123, which facilitates the second focusing ring 120 to surround the sidewall and part of the bottom of the wafer 200, thereby helping the second focusing ring 120 to provide a better effect of providing a balanced plasma.

[0057] In one embodiment, along the radial direction of the second focusing ring 120, the main body 121 includes an outer ring portion 123 located on the outer periphery and an inner ring portion 124 located on the inner periphery. The top surface height of the inner ring portion 124 is lower than the top surface height of the outer ring portion 123. The sidewall of the outer ring portion 123 is connected to the top of the inner ring portion 124. The inner ring portion 124 is disposed below the wafer 200 and surrounds the stage 220, and the outer ring portion 123 is used to surround the wafer 200. The outer ring portion 123 covers a portion of the top of the first focusing ring 110, and the inner ring portion 124 covers the remaining portion of the top of the first focusing ring 110.

[0058] In this embodiment, the angle between the inner sidewall of the outer ring portion 123 and the top surface of the inner ring portion 124 is an obtuse angle, which helps to reduce the probability that the edge of the wafer 200 comes into contact with the main body portion 121, thereby helping to reduce the probability that the edge of the wafer 200 is damaged by collision.

[0059] As an example, the angle θ between the inner sidewall of the outer ring portion 123 and the top surface of the inner ring portion 124 (e.g.) Figure 5 (As shown) The range is 110° to 160°.

[0060] In this embodiment, the second focusing ring 120 includes a silicon carbide ring, a quartz ring, an alumina ceramic ring, or a silicon carbide ceramic ring.

[0061] The reason why the second focusing ring 120 can be a silicon carbide ring, a quartz ring, an alumina ceramic ring, or a silicon carbide ceramic ring is similar to the reason why the first focusing ring 110 can be a silicon carbide ring, a quartz ring, an alumina ceramic ring, or a silicon carbide ceramic ring, so it will not be repeated here.

[0062] In other embodiments, the material of the second focusing ring may also be other materials that are resistant to plasma corrosion and have good thermal conductivity and thermal stability.

[0063] In this embodiment, the first focusing ring 110 and the second focusing ring 120 are made of the same material, which helps to reduce process costs. As an example, the first focusing ring 110 and the second focusing ring 120 are both selected from silicon carbide rings, quartz rings, alumina ceramic rings, and silicon carbide ceramic rings.

[0064] The lifting assembly 130 is used to adjust the distance between the bottom surface of the main body 121 and the top surface of the first focusing ring 110, so that when the heights of the second focusing ring 120 and the first focusing ring 110 gradually decrease due to plasma bombardment (e.g. Figure 5 As shown), this ensures that the top surface of the main body 121 remains within a preset height range (e.g., Figure 6 As shown in the figure, this results in a better morphology of the plasma sheath layer (not shown) at the edge of wafer 200.

[0065] Figure 9 At the beginning of the maintenance cycle, under the action of the focusing ring structure in this embodiment of the invention, the etching rate of each region of the wafer is... Figure 10 At the end of the maintenance cycle, under the action of the focusing ring structure in this embodiment of the invention, the etching rate of each region of wafer 200 is relatively consistent with the etching rate at the beginning of the maintenance cycle. It can be seen that when the focusing ring structure is applied to the plasma etching equipment, at the end of the maintenance cycle, the etching rate of each region of wafer 200 is relatively consistent with the etching rate at the beginning of the maintenance cycle.

[0066] Pink represents the lowest etching rate, and orange represents the highest etching rate.

[0067] During the process of the lifting assembly 130 adjusting the distance W between the bottom surface of the main body 121 and the top surface of the first focusing ring 110, the side wall of the extension 122 and the side wall of the first focusing ring 110 are always in contact. The first focusing ring 110 is fixedly mounted on the base 210 of the plasma equipment, so that the charge on the second focusing ring 120 can be conducted to the base 210 through the first focusing ring 110. Accordingly, during the plasma processing, the charge is not easy to accumulate on the second focusing ring 120, that is, the potential difference is not easy to form between the second focusing ring 120 and the base 210, thereby reducing the probability of arc discharge caused by potential difference, thereby reducing the probability of the wafer to be processed being damaged, and also improving the process stability of plasma processing.

[0068] Furthermore, during the process of adjusting the distance W between the bottom surface of the main body 121 and the top surface of the first focusing ring 110 by the lifting assembly 130, the side wall of the extension 122 always has a contact portion with the side wall of the first focusing ring 110, thereby forming a sealed cavity. This keeps the gas outside the second focusing ring 120 and the first focusing ring 110 blocked outside the cavity, preventing the accumulation of charge inside the cavity. This also reduces the probability of damage to the second focusing ring 120 and the first focusing ring 110. The extension 122 is located on both sides of the first focusing ring 110, which also helps to improve the stability of the second focusing ring 120 during the adjustment of the distance W between the bottom surface of the main body 121 and the top surface of the first focusing ring 110. It also helps to increase the contact area between the extension 122 and the side wall of the first focusing ring 110 within the preset stroke range of height adjustment, thereby improving the effect of conducting the charge on the main body 121 to the base 210 and making it less likely for the charge to accumulate on the second focusing ring 120.

[0069] In this embodiment, the lifting assembly 130 includes: a push pin 131, disposed at the bottom of the second focusing ring 120 and abutting against the second focusing ring 120; and a transmission component 132, fixedly connected to the bottom of the push pin 131, the transmission component 132 being used to drive the push pin 131 to move up and down in the vertical direction.

[0070] The transmission component 132 drives the ejector pin 131 to move up and down in the vertical direction, so that the ejector pin 131 can lift the second focusing ring 120 in the vertical direction, thereby reducing the difficulty of adjusting the distance W between the bottom surface of the main body 121 and the top surface of the first focusing ring 110.

[0071] Specifically, the number of pins in the same lifting assembly 130 is multiple; the transmission component 132 includes: a support component 133, which is fixedly connected to the bottom of the pin 131 in the same lifting assembly 130; and a lifting column 134, which is fixedly disposed at the bottom of the support component 133.

[0072] The fact that there are multiple ejector pins 131 in the same lifting assembly 130 is beneficial to improving the stability of the second focusing ring 120 during the process of the ejector pins 131 lifting the second focusing ring 120. Moreover, the multiple ejector pins 131 in the same lifting assembly 130 correspond to the same lifting column 134, which helps to reduce the number of lifting columns 134, thereby reducing the impact of setting up lifting columns 134 on the internal environment of the plasma equipment chamber, and also helps to reduce the difficulty of the process and reduce the process cost.

[0073] More specifically, the same lifting assembly 130 has two pins 131, one of which is a first pin 1311 located on one side of the inner circumference of the first focusing ring 110, and the other is a second pin 1312 located on one side of the outer circumference of the first focusing ring 110. Along the radial direction of the first focusing ring 110, the first pin 1311 and the second pin 1312 of the same lifting assembly 130 are symmetrically arranged on both sides of the first focusing ring 110, which is beneficial to further improve the stability of the second focusing ring 120 during the process of the pins 131 lifting the second focusing ring 120.

[0074] As an example, in a direction parallel to the top surface of the lifting column 134, the distance from the lifting column 134 to the first ejector pin 1311 is equal to the distance from the lifting column 134 to the second ejector pin 1312. This makes it easier for the center of gravity of the lifting assembly 130 to extend in the direction of the height of the lifting column 134, which is beneficial to improving the structural stability of the lifting assembly 130.

[0075] In this embodiment, the ejector pin 131 is disposed at the bottom of the extension 122 and abuts against the extension 122, which helps to reduce the difficulty of the ejector pin 131 abutting against the bottom of the second focusing ring 120, and also helps to reduce the height of the ejector pin 131, thereby helping to reduce the process cost.

[0076] In other embodiments, the ejector pin is disposed at the bottom of the main body and abuts against the main body. For example, the ejector pin passes through the first focusing ring and is disposed at the bottom of the main body; or, the sidewall of the main body protrudes from the sidewall of the extension at the bottom, and the ejector pin is disposed at the bottom of the protruding portion of the main body.

[0077] In this embodiment, the material of the ejector pin 131 is an insulating material.

[0078] In this embodiment, there are multiple lifting components 130, and the multiple lifting components 130 are evenly arranged around the center of the first focusing ring 110. This is beneficial to make the force on each lifting component 130 more uniform during the process of adjusting the distance W between the bottom surface of the main body 121 and the top surface of the first focusing ring 110, thereby improving the stability of the second focusing ring 120 and also improving the service life of each lifting component 130.

[0079] Specifically, the number of lifting components 130 is at least three, so that during the process of adjusting the distance W between the bottom surface of the main body 121 and the top surface of the first focusing ring 110, the lifting components 130 can stably support the second focusing ring 120, thereby improving the stability of the second focusing ring 120.

[0080] In this embodiment, the height of the extension 122 is less than or equal to the height of the first focusing ring 110, and the preset travel range of the height adjustment is less than the height of the extension 122, so as to ensure that the sidewall of the extension 122 and the sidewall of the first focusing ring 110 always have a contact portion.

[0081] It is understandable that, in order to ensure that the height of the top surface of the main body 121 is within a preset height range, the distance W between the bottom surface of the main body 121 and the top surface of the first focusing ring 110 can be adjusted after a certain process time within a maintenance cycle.

[0082] Accordingly, this utility model also provides an plasma device.

[0083] In this embodiment, in conjunction with the reference Figures 4 to 8 The plasma device includes: a chamber (not shown); a base 210 located in the chamber, the base having a stage 220 for supporting a wafer 200; and a focusing ring structure (not shown) as described in any embodiment of the present invention, the focusing ring structure being disposed on the base 210 and surrounding the stage 220.

[0084] The lifting assembly 130 is used to adjust the distance between the bottom surface of the main body 121 and the top surface of the first focusing ring 110, so that as the height of the second focusing ring 120 and the first focusing ring 110 gradually decreases due to plasma bombardment, the top surface of the main body 121 is kept within a preset height range, thereby making the morphology of the plasma sheath layer (not shown) at the edge of the wafer 200 better.

[0085] In this embodiment, the plasma device includes a plasma etching device.

[0086] The plasma etching apparatus is used to remove material using plasma. In other embodiments, the plasma apparatus may be other suitable devices.

[0087] Figure 9 At the beginning of the maintenance cycle, under the action of the focusing ring structure in this embodiment of the invention, the etching rate of each region of the wafer is... Figure 10At the end of the maintenance cycle, under the action of the focusing ring structure in this embodiment of the invention, the etching rate of each region of the wafer 200 is relatively consistent with the etching rate at the beginning of the maintenance cycle. It can be seen that when the plasma equipment includes a plasma etching equipment, the etching rate of each region of the wafer 200 at the end of the maintenance cycle is relatively consistent with the etching rate at the beginning of the maintenance cycle.

[0088] Pink represents the lowest etching rate, and orange represents the highest etching rate.

[0089] During the process of adjusting the distance W between the bottom surface of the main body 121 and the top surface of the first focusing ring 110, the side wall of the extension 122 and the side wall of the first focusing ring 110 are always in contact. The first focusing ring 110 is fixedly mounted on the base 210 of the plasma device, so that the charge on the second focusing ring 120 can be conducted to the base 210 through the first focusing ring 110. Accordingly, during the plasma processing, the charge is less likely to accumulate on the second focusing ring 120, that is, the potential difference is less likely to form between the second focusing ring 120 and the base 210, thereby reducing the probability of arc discharge caused by potential difference, and thus reducing the probability of damage to the wafer 200 to be processed, and also improving the process stability of plasma processing.

[0090] Furthermore, during the process of adjusting the distance W between the bottom surface of the main body 121 and the top surface of the first focusing ring 110 by the lifting assembly 130, the side wall of the extension 122 always has a contact portion with the side wall of the first focusing ring 110, thereby forming a sealed cavity. This keeps the gas outside the second focusing ring 120 and the first focusing ring 110 blocked outside the cavity, preventing the accumulation of charge inside the cavity. This also reduces the probability of damage to the second focusing ring 120 and the first focusing ring 110. The extension 122 is located on both sides of the first focusing ring 110, which also helps to improve the stability of the second focusing ring 120 during the adjustment of the distance W between the bottom surface of the main body 121 and the top surface of the first focusing ring 110. It also helps to increase the contact area between the extension 122 and the side wall of the first focusing ring 110 within the preset stroke range of height adjustment, thereby improving the effect of conducting the charge on the main body 121 to the base 210 and making it less likely for the charge to accumulate on the second focusing ring 120.

[0091] The second focusing ring 120 covers the top and sidewalls of the first focusing ring 110, so that the consumption of the first focusing ring 110 under plasma bombardment is less than that of the second focusing ring 120 under plasma bombardment. This makes the replacement frequency of the first focusing ring 110 less than that of the second focusing ring 120, thereby helping to save process costs.

[0092] In this embodiment, the lifting assembly 130 includes: a pin 131 that penetrates the base 210 in the vertical direction and is slidably disposed in the base 210, and the pin 131 abuts against the bottom of the second focusing ring 120; and a transmission component 132 located on the side of the base 210 opposite to the focusing ring structure, the transmission component 132 being fixedly connected to the bottom of the pin 131, and the transmission component 132 being used to drive the pin 131 to move up and down in the vertical direction.

[0093] The transmission component 132 drives the ejector pin 131 to move up and down in the vertical direction, so that the ejector pin 131 can lift the second focusing ring 120 in the vertical direction, thereby reducing the difficulty of adjusting the distance W between the bottom surface of the main body 121 and the top surface of the first focusing ring 110.

[0094] In this embodiment, the ejector pin 131 is disposed at the bottom of the extension 122 and abuts against the extension 122. The difference between the height of the ejector pin 131 and the height of the base 210 is less than the height of the first focusing ring 110.

[0095] The ejector pin 131 is disposed at the bottom of the extension 122 and abuts against the extension 122, which helps to reduce the difficulty of the ejector pin 131 abutting against the bottom of the second focusing ring 120.

[0096] The difference between the height of the ejector pin 131 and the height of the base 210 is less than the height of the first focusing ring 110, which helps to reduce the height of the ejector pin 131 and thus helps to reduce the process cost.

[0097] For a detailed description of the focusing ring structure, please refer to the detailed description of the foregoing embodiments, which will not be repeated in this embodiment.

[0098] While the present invention has been disclosed above, it is not limited thereto. Any person skilled in the art can make various modifications and alterations without departing from the spirit and scope of the present invention; therefore, the scope of protection of the present invention should be determined by the scope defined in the claims.

Claims

1. A focus ring structure, characterized by, The application is applied to a plasma device, comprising: a first focus ring, used for fixing a base provided on the plasma device; a second focus ring, comprising a main body part located on top of the first focus ring, and extension parts protruding from the bottom surface of the main body part and located on both sides of the first focus ring, the extension parts and the main body part form a groove, the groove accommodates at least part of the first focus ring in a preset range of height adjustment, so that the side wall of the groove is in contact with the side wall of the first focus ring; a lifting assembly provided at the bottom of the second focus ring, used for adjusting the distance between the bottom surface of the main body part and the top surface of the first focus ring in the preset range of height adjustment.

2. The focus ring structure of claim 1, wherein, The plasma device further comprises a carrier provided on the base, used for carrying a wafer; along the radial direction of the second focus ring, the main body part comprises an outer ring part located on one side of the outer periphery, and an inner ring part located on one side of the inner periphery, the top surface height of the inner ring part is lower than that of the outer ring part, the side wall of the outer ring part is connected with the top of the inner ring part, the inner ring part is used for being arranged below the wafer and surrounding the carrier, and the outer ring part is used for surrounding the wafer; the extension parts protrude from the bottom surface of the outer ring part and the bottom surface of the inner ring part respectively.

3. The focus ring structure of claim 2, wherein, The included angle between the inner side wall of the outer ring part and the top surface of the inner ring part is obtuse.

4. The focus ring structure of any one of claims 1 to 3, wherein, The lifting assembly comprises: a thimble provided at the bottom of the second focus ring and in abutment with the second focus ring; a transmission component fixedly connected with the bottom of the thimble, used for driving the thimble to lift in the vertical direction.

5. The focus ring structure of claim 4, wherein, The number of thimbles of the same lifting assembly is multiple; the transmission component comprises: a supporting component fixedly connected with the bottom of the thimble of the same lifting assembly; and a jacking column fixedly provided at the bottom of the supporting component.

6. The focus ring structure of claim 5, wherein, The number of thimbles of the same lifting assembly is two, one of which is a first thimble located on one side of the inner periphery of the first focus ring, and the other is a second thimble located on one side of the outer periphery of the first focus ring; along the radial direction of the first focus ring, the first thimble and the second thimble of the same lifting assembly are symmetrically arranged on both sides of the first focus ring.

7. The focus ring structure of claim 6, wherein, In the direction parallel to the top surface of the jacking column, the distance from the jacking column to the first thimble is equal to the distance from the jacking column to the second thimble.

8. The focus ring structure of claim 4, wherein, The thimble is provided at the bottom of the extension part and in abutment with the extension part.

9. The focus ring structure of claim 1, wherein, The height of the extension part is less than or equal to the height of the first focus ring, and the preset range of height adjustment is less than the height of the extension part.

10. The focus ring structure of claim 1, wherein, The number of lifting assemblies is multiple, and the multiple lifting assemblies are uniformly arranged around the center of the first focus ring.

11. The focus ring structure of claim 10, wherein, The number of lifting assemblies is at least three.

12. The focus ring structure of claim 1, wherein, The type of the first focus ring includes a silicon carbide ring, a quartz ring, an alumina ceramic ring or a silicon carbide ceramic ring; The type of the second focus ring includes a silicon carbide ring, a quartz ring, an alumina ceramic ring or a silicon carbide ceramic ring.

13. The focus ring structure of claim 1 or 12, wherein, The material of the first focus ring is the same as that of the second focus ring.

14. The focus ring structure of claim 1, wherein, The focusing ring structure is applied to a plasma etching device.

15. A plasma device, characterized by It comprises: a chamber; a pedestal in the chamber, the pedestal having a carrier for carrying a wafer; the focusing ring structure as claimed in any one of claims 1 to 14 is arranged on the pedestal and surrounds the carrier.

16. The plasma apparatus of claim 15, wherein, The lifting assembly comprises a top pin penetrating the pedestal in a vertical direction and slidingly arranged in the pedestal, and the top pin abuts against the bottom of the second focusing ring; a transmission component on the side of the pedestal away from the focusing ring structure, the transmission component being fixedly connected with the bottom of the top pin, and the transmission component being used to drive the top pin to lift in a vertical direction.

17. The plasma apparatus of claim 16, wherein, The top pin is arranged at the bottom of the extension and abuts against the extension, and the difference between the height of the top pin and the height of the pedestal is less than the height of the first focusing ring.

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