Edge ring for etching equipment and etching equipment
By setting an annular groove on the edge ring of the etching equipment to collect polymers, the problem of abnormal shutdown of the electrostatic chuck caused by polymer accumulation is solved, the etching efficiency and quality are improved, and the service life of the equipment is extended.
Patent Information
- Application Number
- CN202421168452.6
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-05-27
- Publication Date
- 2025-01-21
- Estimated Expiration
- 2034-05-27
AI Technical Summary
During the silicon carbide wafer etching process, the polymer accumulates on the surface of the silicon ring and causes abnormal back heating effect (BHE) shutdown of the electrostatic chuck, and even leads to product scrapping.
An edge ring is designed for etching equipment. The edge ring is provided with an annular groove to collect polymers and shed polymer particles produced during the etching process to prevent them from reaching the surface of the electrostatic chuck.
By collecting polymer and shed polymer particles, BHE abnormalities in the electrostatic chuck are reduced, etching efficiency and quality are improved, equipment maintenance burden is reduced, and the service life of the edge ring is extended.
Smart Images
Figure CN222380546U_ABST
Abstract
Description
Technical Field
[0001] The present application relates to the field of semiconductor technology, and in particular to an edge ring for an etching device and the etching device. Background Art
[0002] In the silicon carbide wafer etching manufacturing process, dry etching has become the mainstream etching method. Dry etching uses radio frequency power to generate highly reactive plasma from the reaction gas, physically bombarding and chemically reacting the wafer to selectively remove the target area and obtain the desired pattern.
[0003] During the silicon carbide etching process, the contact pad (Pad) etches the aluminum layer and etches the oxide layer on the aluminum layer. After over-etching, part of the aluminum layer will be etched, and over-etching will always exist. Over-etching will produce polymers, and the polymers will adhere to the surface of the silicon ring. When the polymers on the surface of the silicon ring accumulate to a certain extent, the surface of the polymer will begin to lift and fall off. During the processing, the falling of the polymer may cause the backside heating effect (BHE) of the electrostatic chuck to abnormally shut down, and even cause the product to be scrapped. Utility Model Content
[0004] In view of this, an embodiment of the present application provides an edge ring for an etching device and an etching device to solve at least one problem existing in the background technology.
[0005] In a first aspect, an embodiment of the present application provides an edge ring for an etching device, the etching device comprising an electrostatic chuck, the inner space of the edge ring is used to set the electrostatic chuck, the electrostatic chuck is used to adsorb a wafer to a first surface of the electrostatic chuck, and a predetermined gap is provided between the inner side wall of the edge ring and the side wall of the electrostatic chuck;
[0006] An annular groove is arranged on the second surface of the edge ring around the inner space of the ring, and the annular groove is used to collect polymers generated during the etching process of the wafer, wherein the first surface and the second surface face the same direction.
[0007] In combination with the first aspect of the present application, in an optional implementation, an orthographic projection of the side wall of the wafer in the axial direction of the edge ring and an orthographic projection of the annular groove in the axial direction of the edge ring have an overlapping portion.
[0008] In combination with the first aspect of the present application, in an optional embodiment, the first groove wall of the annular groove intersects with the inner side wall of the edge ring to form a sharp angle, and the distance between the orthographic projection of the sharp angle in the axial direction of the edge ring and the orthographic projection of the side wall of the wafer in the axial direction of the edge ring is less than or equal to 0.5 mm.
[0009] In combination with the first aspect of the present application, in an optional embodiment, the sharp corner is lower than the first surface in the axial direction of the edge ring, and the distance between the sharp corner and the first surface in the axial direction of the edge ring is less than or equal to 0.8 mm.
[0010] In combination with the first aspect of the present application, in an optional implementation, the first groove wall is a curved surface structure.
[0011] In combination with the first aspect of the present application, in an optional embodiment, the distance from the intersection of the first groove wall of the annular groove and the second surface to the inner side wall of the edge ring is less than or equal to 0.3 mm.
[0012] In combination with the first aspect of the present application, in an optional embodiment, an angle is formed between the second groove wall of the annular groove and the second surface, and the angle ranges from 30° to 85°.
[0013] In combination with the first aspect of the present application, in an optional implementation manner, the predetermined gap ranges from 0.1 mm to 0.3 mm.
[0014] In combination with the first aspect of the present application, in an optional implementation, the maximum depth of the annular groove is 1 / 4 to 3 / 4 of the thickness of the edge ring.
[0015] In a second aspect, an embodiment of the present application provides an etching device, including an edge ring for an etching device provided by any of the above embodiments.
[0016] The embodiment of the present application provides an edge ring for etching equipment, which is provided with an annular groove. The annular groove can collect polymers generated during the etching process and detached polymer particles, reduce the detached polymer particles from reaching the surface of the electrostatic chuck, and further reduce the BHE abnormalities of the electrostatic chuck during the etching process, reduce the equipment maintenance burden, and improve the wafer etching efficiency and etching quality.
[0017] Additional aspects and advantages of the present application will be given in part in the description below, and in part will become apparent from the description below, or will be learned through the practice of the present application. BRIEF DESCRIPTION OF THE DRAWINGS
[0018] The drawings described herein are used to provide a further understanding of the present application and constitute a part of the present application. The illustrative embodiments of the present application and their descriptions are used to explain the present application and do not constitute an improper limitation on the present application. In the drawings:
[0019] Figure 1 A schematic diagram of the positional relationship between an edge ring and an electrostatic chuck in the prior art provided in an embodiment of the present application;
[0020] Figure 2 A top view of the positional relationship between the electrostatic chuck and the edge ring provided in an embodiment of the present application;
[0021] Figure 3 A schematic diagram of the positional relationship between the edge ring and the electrostatic chuck of a wafer in an etching state provided in an embodiment of the present application;
[0022] Figure 4 for Figure 3 The enlarged view of point A in the middle;
[0023] Figure 5 A schematic diagram of the partial position relationship between the edge ring and the electrostatic chuck of a wafer in an etching state provided by another embodiment of the present application;
[0024] Figure 6 for Figure 5 Enlarged view of point B in the middle.
[0025] Reference numerals:
[0026] m, wafer;
[0027] 10. Electrostatic chuck; 110. First surface; 20. Edge ring; 210. Inner wall of the ring; 220. Second surface; 230. Groove; 231. Sharp corner; 232. First groove wall; 233. Second groove wall. DETAILED DESCRIPTION
[0028] The exemplary embodiments disclosed in the present application will be described in more detail below with reference to the accompanying drawings. Although the exemplary embodiments of the present application are shown in the accompanying drawings, it should be understood that the present application can be implemented in various forms and should not be limited by the specific embodiments described herein. On the contrary, these embodiments are provided to enable a more thorough understanding of the present application and to fully convey the scope disclosed in the present application to those skilled in the art.
[0029] In the following description, a large number of specific details are given to provide a more thorough understanding of the present application. However, it is obvious to those skilled in the art that the present application can be implemented without one or more of these details. In other examples, in order to avoid confusion with the present application, some technical features known in the art are not described; that is, all features of the actual embodiments are not described here, and well-known functions and structures are not described in detail.
[0030] In the drawings, the sizes of layers, regions, elements and their relative sizes may be exaggerated for clarity. Like reference numerals denote like elements throughout.
[0031] It should be understood that when an element or layer is referred to as "on ...", "adjacent to ...", "connected to" or "coupled to" other elements or layers, it can be directly on, adjacent to, connected to or coupled to other elements or layers, or there can be intervening elements or layers. On the contrary, when an element is referred to as "directly on ...", "directly adjacent to ...", "directly connected to" or "directly coupled to" other elements or layers, there is no intervening element or layer. It should be understood that although the terms first, second, third, etc. can be used to describe various elements, components, regions, layers and / or parts, these elements, components, regions, layers and / or parts should not be limited by these terms. These terms are only used to distinguish one element, component, region, layer or part from another element, component, region, layer or part. Therefore, without departing from the teachings of the present application, the first element, component, region, layer or part discussed below can be represented as the second element, component, region, layer or part. And when the second element, component, region, layer or part is discussed, it does not indicate that the present application necessarily has the first element, component, region, layer or part.
[0032] Spatially relative terms such as "under", "beneath", "below", "under", "above", "above", etc., may be used here for convenience of description to describe the relationship between an element or feature shown in the figure and other elements or features. It should be understood that in addition to the orientation shown in the figure, the spatial relationship terms are intended to also include different orientations of the device in use and operation. For example, if the device in the accompanying drawings is turned over, then the elements or features described as "under other elements" or "under it" or "under it" will be oriented as "on" other elements or features. Therefore, the exemplary terms "under" and "under" may include both upper and lower orientations. The device can be oriented otherwise (rotated 90 degrees or other orientations) and the spatial descriptors used herein are interpreted accordingly.
[0033] The purpose of the terms used herein is only to describe specific embodiments and is not intended to be limiting of the present application. When used herein, the singular forms "one", "an" and "said / the" are also intended to include plural forms, unless the context clearly indicates otherwise. It should also be understood that the terms "consisting of" and / or "comprising", when used in this specification, determine the presence of the features, integers, steps, operations, elements and / or parts, but do not exclude the presence or addition of one or more other features, integers, steps, operations, elements, parts and / or groups. When used herein, the term "and / or" includes any and all combinations of the relevant listed items.
[0034] In order to thoroughly understand the present application, detailed steps and detailed structures will be presented in the following description to illustrate the technical solution of the present application. The preferred embodiments of the present application are described in detail below, but in addition to these detailed descriptions, the present application may also have other implementation methods.
[0035] Figure 1 FIG. 2 shows a schematic diagram of the positional relationship among an electrostatic chuck, an edge ring, and a wafer in a plasma etching environment in the prior art. Figure 1 The surface of the edge ring shown in the figure is a planar structure. The edge ring is used to prevent the polymer generated during the etching process from contaminating the surface of the electrostatic chuck. The polymer generated during the wafer etching process adheres to the surface of the edge ring. When the polymer thickness reaches a certain level, the polymer surface near the electrostatic chuck may fall off. The detached polymer particles may contaminate the electrostatic chuck, which may cause the electrostatic chuck to shut down abnormally and affect the wafer etching efficiency and etching quality.
[0036] In response to the above technical problems, an embodiment of the present application provides an edge ring for an etching device, which is provided with an annular groove. The annular groove can collect polymers generated during the etching process and detached polymer particles, thereby preventing the polymer particles from reaching the surface of the electrostatic chuck, thereby avoiding BHE abnormalities of the electrostatic chuck during the etching process, and ensuring the wafer etching efficiency and etching quality.
[0037] The edge ring for etching equipment provided in an embodiment of the present application is described in detail below with reference to the accompanying drawings.
[0038] Specifically, Figure 2 and Figure 3 As shown, the edge ring for etching equipment provided in the embodiment of the present application, the material of the edge ring 20 is silicon dioxide, the etching equipment is a plasma etching equipment, and the etching equipment includes an electrostatic chuck 10, and the electrostatic chuck 10 is located in the inner ring space of the edge ring 20. The electrostatic chuck 10 adsorbs the wafer m on the first surface 110 of the electrostatic chuck 10 through the action of electrostatic force. There is a gap between the first surface 110 and the wafer m, and the gap allows gas to pass. There is a predetermined gap between the inner side wall 210 of the edge ring 20 and the side wall of the electrostatic chuck 10.
[0039] An annular groove 230 is disposed on the second surface 220 of the edge ring 20 around the inner space of the ring, and the annular groove 230 is used to collect polymers generated during the etching process of the wafer m, wherein the first surface 110 and the second surface 220 face the same direction.
[0040] By providing the annular groove 230 on the edge ring 20 , more polymers generated during the etching process can be collected, thereby improving the etching efficiency.
[0041] The polymer generated during the etching process of the wafer m moves with the airflow in the etching equipment and adheres to the second surface 220 of the edge ring 20. The edge surface layer of the polymer accumulated to a certain thickness is easily lifted and fallen off due to the reduction of stress.
[0042] In view of the above technical problems, the embodiment of the present application enables the orthographic projection of the side wall of the wafer m in the axial direction of the edge ring 20 to overlap with the orthographic projection of the annular groove 230 in the axial direction of the edge ring 20 during the etching process of the wafer m. Figure 3 The dotted line S shown in FIG. 2 is the axial direction of the edge ring 20 .
[0043] In the embodiment of the present application, the side wall of the wafer m and the annular groove 230 have an overlapping portion in the orthographic projection in the axial direction of the edge ring 20, which can not only collect more polymers, but also when the polymer accumulates to a certain thickness, the surface of the polymer rises and falls off, and the annular groove 230 can also collect more polymer particles that rise and fall off, thereby preventing the electrostatic chuck 10 from shutting down abnormally due to the falling polymer particles, thereby improving the utilization rate of the etching equipment, saving costs, and greatly extending the service life of the edge ring 20.
[0044] In an alternative embodiment, if Figure 3 and Figure 4 As shown, the first groove wall 232 of the annular groove 230 intersects with the inner side wall 210 of the edge ring 20 to form a sharp corner 231, and the distance between the orthographic projection of the top of the sharp corner 231 in the axial direction of the edge ring 20 and the orthographic projection of the side wall of the wafer m in the axial direction of the edge ring 20 is Figure 4 As shown in FIG. , L5 is less than or equal to 0.5 mm.
[0045] When the thickness of the detached polymer particles accumulates to a depth close to the annular groove 230, the detached polymer particles are easily attached to the sharp corner 231. Due to the small attachment area, the detached polymer particles slide into the annular groove along the first groove wall 232 of the annular groove 230, preventing the detached polymer particles from moving to the surface of the electrostatic chuck 10. The distance between the top of the sharp corner 231 and the orthographic projection of the side wall of the wafer m in the axial direction of the edge ring 20 is less than or equal to 0.5 mm, which enables the annular groove 230 to collect more polymers and polymer particles.
[0046] In an alternative embodiment, if Figure 4 As shown, the top of the sharp corner 231 is lower than the first surface 110 in the axial direction of the edge ring 20 , and the distance between the sharp corner 231 and the first surface 110 in the axial direction of the edge ring 20 is less than or equal to 0.8 mm.
[0047] The distance between the sharp corner 231 and the first surface 110 in the axial direction of the edge ring 20 is Figure 4As shown in FIG. 1 , L1 less than or equal to 0.8 mm can make the annular groove 230 accumulate thicker polymer and further collect more polymer. When L1 is greater than 0.8 mm, some of the polymer falling from above cannot fall into the annular groove 230 .
[0048] In an alternative embodiment, if Figure 4 As shown, the first groove wall 232 is a curved surface structure, which facilitates the polymer particles at the sharp corner 231 to slide into the annular groove 230 .
[0049] In an alternative embodiment, if Figure 5 and Figure 6 As shown, the distance from the intersection of the first groove wall 232 of the annular groove 230 and the second surface to the inner side wall 210 of the edge ring 20 is Figure 6 In the example shown in FIG. 2 , L2 is less than or equal to 0.3 mm. In this way, the processing requirements of the edge ring 20 can be reduced, and the adhesion area of the detached polymer can be reduced, so that the polymer particles attached to the sharp corner 231 can slide into the annular groove 230 .
[0050] In an alternative embodiment, Figure 4 FIG. 4 shows an angle a formed between the second groove wall 233 of the annular groove 230 and the second surface 220 of the edge ring 20 , wherein the angle a ranges from 30° to 85°.
[0051] The first groove wall 232 and the second groove wall 233 are connected through the groove bottom to form an annular groove 230. The first groove wall 232 is the inner side wall 210 close to the edge ring 20, and the second groove wall 233 is away from the inner side wall 210 of the edge ring 20. The shape structure of the annular groove 230 is not limited in the embodiment of the present application.
[0052] In an alternative embodiment, if Figure 6 As shown, the predetermined gap is Figure 6 The size range of L3 shown in FIG. 1 is 0.1 mm to 0.3 mm. The predetermined gap in this size range is conducive to the passage of the cavity airflow, and the small by-products are taken away by the airflow.
[0053] When the size of L3 is less than 0.1 mm, the predetermined gap is too small to facilitate the airflow in the cavity. When the size of L3 is greater than 0.3 mm, larger particles of by-products are easily accumulated, affecting the airflow in the cavity.
[0054] In an alternative embodiment, if Figure 5 and Figure 6 As shown, the maximum depth of the annular groove 230 is Figure 6The L4 shown in FIG. 1 is 1 / 4 to 3 / 4 of the thickness of the edge ring 20. The annular groove 230 in this ratio range can collect more polymers and ensure the structural strength of the edge ring 20.
[0055] When L4 occupies more than 3 / 4 of the thickness of the edge ring 20, the structural strength of the edge ring 20 is affected. When L4 occupies less than 1 / 4 of the thickness of the edge ring 20, the amount of polymer collected by the annular groove 230 is reduced.
[0056] The embodiment of the present application further provides an etching device, comprising the edge ring 20 for etching device provided in any of the above embodiments. The etching device further comprises an electrostatic chuck 10, and the inner space of the edge ring 20 is used to set the electrostatic chuck 10.
[0057] The polymer generated during the plasma etching of the wafer m is collected by the annular groove 230 set in the edge ring 20. The edge ring 20 with the annular groove 230 can collect more polymers than the edge ring 20 with a planar structure, thereby improving the utilization rate of the etching equipment, saving costs, and extending the service life of the edge ring 20.
[0058] It should be understood that the above embodiments are exemplary and are not intended to include all possible implementations included in the claims. Various modifications and changes may be made on the basis of the above embodiments without departing from the scope of the present disclosure. Similarly, the various technical features of the above embodiments may be arbitrarily combined to form other embodiments of the present application that may not be explicitly described. Therefore, the above embodiments only express several implementations of the present application and do not limit the scope of protection of the patent of this application.
Claims
1. An edge ring for an etching device, characterized in that: The etching device comprises an electrostatic chuck, the inner space of the edge ring is used to set the electrostatic chuck, the electrostatic chuck is used to adsorb the wafer to the first surface of the electrostatic chuck, and there is a predetermined gap between the inner side wall of the edge ring and the side wall of the electrostatic chuck; An annular groove is arranged on the second surface of the edge ring around the inner space of the ring, and the annular groove is used to collect polymers generated during the etching process of the wafer, wherein the first surface and the second surface face the same direction.
2. The edge ring for etching equipment according to claim 1, characterized in that: An orthographic projection of the side wall of the wafer in the axial direction of the edge ring and an orthographic projection of the annular groove in the axial direction of the edge ring have an overlapping portion.
3. The edge ring for etching equipment according to claim 2, characterized in that: The first groove wall of the annular groove intersects with the inner side wall of the edge ring to form a sharp angle, and the distance between the orthographic projection of the sharp angle in the axial direction of the edge ring and the orthographic projection of the side wall of the wafer in the axial direction of the edge ring is less than or equal to 0.5 mm.
4. The edge ring for etching equipment according to claim 3, characterized in that: The sharp corner is lower than the first surface in the axial direction of the edge ring, and the distance between the sharp corner and the first surface in the axial direction of the edge ring is less than or equal to 0.8 mm.
5. The edge ring for etching equipment according to claim 3, characterized in that: The first groove wall is a curved surface structure.
6. The edge ring for etching equipment according to claim 2, characterized in that: The distance from the intersection of the first groove wall of the annular groove and the second surface to the inner side wall of the edge ring is less than or equal to 0.3 mm.
7. The edge ring for etching equipment according to claim 1, characterized in that: An angle is formed between the second groove wall of the annular groove and the second surface, and the angle ranges from 30° to 85°.
8. The edge ring for etching equipment according to claim 1, characterized in that: The predetermined gap ranges from 0.1 mm to 0.3 mm.
9. The edge ring for etching equipment according to claim 1, characterized in that: The maximum depth of the annular groove is 1 / 4 to 3 / 4 of the thickness of the edge ring.
10. An etching device, characterized in that: The invention comprises an edge ring for an etching device as claimed in any one of claims 1 to 9.