Dielectric window and semiconductor process chamber
By setting a concave area in the center of the bottom surface of the medium window, similar to the arch bridge effect, the problem of particle production in the dielectric window in the semiconductor process chamber is solved, the number of particle is reduced and the process quality is improved.
Patent Information
- Application Number
- CN202321836891.5
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2023-07-13
- Publication Date
- 2024-12-24
- Estimated Expiration
- 2033-07-13
AI Technical Summary
The amount of particulate matter generated by the dielectric window in the semiconductor process chamber is large, which affects the process results and is difficult to effectively reduce the prior art.
Setting a concave area near the center of the bottom surface of the medium window is similar to the arch bridge effect, reducing the deformation of the bottom surface of the medium window and reducing the possibility of particle peeling.
By setting up a concave area, the peeling phenomenon of particles on the bottom of the dielectric window is reduced, the amount of particles generated by the dielectric window in the semiconductor process chamber is reduced, and the quality index of the process is improved.
Smart Images
Figure CN222233566U_ABST
Abstract
Description
Technical Field
[0001] The present application relates to the field of semiconductor process technology, and in particular to a dielectric window and a semiconductor process chamber. Background Art
[0002] The number of particles in a semiconductor process chamber such as a semiconductor etcher is an important indicator for evaluating process results. The dielectric window of the semiconductor process chamber is a major source of particles. Therefore, how to reduce the number of particles generated by the dielectric window is an urgent problem to be solved by technicians in this field. Utility Model Content
[0003] The embodiments of the present application provide a dielectric window and a semiconductor process chamber, and provide a method for reducing particulate matter generated by the dielectric window.
[0004] The dielectric window provided in an embodiment of the present application is applied to a semiconductor process chamber, wherein the bottom surface of the dielectric window has a concave area, the surface of the concave area is concave toward the top surface of the dielectric window, and the concave area is located in the center area of the bottom surface of the dielectric window.
[0005] Optionally, the surface of the concave area is a surface of revolution, the axis of the surface of revolution extends along the thickness direction of the dielectric window, the generatrix of the surface of revolution is a straight line, the generatrix is coplanar with the axis, and the angle between the generatrix and the axis is less than 90 degrees.
[0006] Optionally, the axis passes through the center of the bottom surface.
[0007] Optionally, the angle between the busbar and the axis is greater than or equal to 85 degrees.
[0008] Optionally, a target intersection is formed between the extension line of the busbar and the axis, and the busbar has a target endpoint on the side away from the target intersection. In a direction parallel to the axis, the distance between the target intersection and the target endpoint is 1 to 4 mm, and in a direction perpendicular to the axis, the distance between the target endpoint and the axis is 133.5 to 320 mm.
[0009] Optionally, the bottom surface of the dielectric window has an edge region, and the surface of the edge region is arranged horizontally.
[0010] Optionally, a region of the bottom surface of the dielectric window between the edge region and the concave region is a transition region, and a surface of the transition region is a curved surface.
[0011] The semiconductor process chamber provided in the embodiments of the present application includes any one of the dielectric windows provided in the embodiments of the present application.
[0012] Optionally, the semiconductor process chamber is provided with a reaction chamber, the dielectric window is sealed above the reaction chamber, and the concave area faces the reaction chamber.
[0013] Optionally, the semiconductor process chamber further includes an upper electrode and a lower electrode, the upper electrode is arranged above the dielectric window, the lower electrode is arranged below the dielectric window, a wafer carrying surface is provided on the top of the lower electrode, and the concave area faces the wafer carrying surface.
[0014] At least one of the above technical solutions adopted in the embodiments of the present application can achieve the following beneficial effects:
[0015] In the embodiment of the present application, by providing a concave area in the center of the bottom surface of the dielectric window, an effect similar to an "arch bridge" can be achieved, which can reduce the deformation of the bottom surface of the dielectric window and reduce the possibility of particles deposited on the bottom surface of the dielectric window being peeled off. In addition, the number of particles generated by the dielectric window during the operation of the semiconductor process chamber can be reduced. BRIEF DESCRIPTION OF THE DRAWINGS
[0016] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the related technologies, the drawings required for use in the embodiments or the related technical descriptions are briefly introduced below. Obviously, the drawings described below are only some embodiments recorded in the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative labor.
[0017] Figure 1 A schematic diagram of a dielectric window provided in an embodiment of the present application;
[0018] Figure 2 A schematic diagram of a dielectric window force analysis provided in an embodiment of the present application;
[0019] Figure 3 A schematic diagram of a semiconductor process chamber provided in an embodiment of the present application.
[0020] Description of reference numerals:
[0021] 100 - semiconductor process chamber; 110 - dielectric window; 111 - bottom surface; 1111 - concave area; 1112 - edge area; 1113 - transition area; 112 - top surface; 120 - reaction chamber; 130 - upper electrode; 140 - lower electrode; 141 - wafer carrying surface; 150 - chamber; 160 - heater. DETAILED DESCRIPTION
[0022] In order to make the purpose, technical solution and advantages of the present application clearer, the technical solution of the present application will be clearly and completely described below in combination with the specific embodiments of the present application and the corresponding drawings. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present application.
[0023] In the description of this application, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a direct connection, or an indirect connection through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances.
[0024] In addition, although the terms used in this application are selected from well-known and commonly used terms, some terms mentioned in the specification of this application may be selected by the applicant at his or her discretion, and their detailed meanings are explained in the relevant parts of the description of this article.
[0025] Furthermore, it is required that the present application be understood not only by the actual terms used but also by the meanings connoted by each term.
[0026] The technical solutions provided by various embodiments of the present application are described in detail below in conjunction with the accompanying drawings.
[0027] The embodiment of the present application provides a dielectric window. The dielectric window provided in the embodiment of the present application is applied to a semiconductor process chamber. Exemplarily, the semiconductor process chamber can be a semiconductor etcher. It should be noted that, taking the semiconductor process chamber as a semiconductor etcher as an example, the dielectric window is located above the etching chamber. During the etching process, the temperature difference between the atmospheric side and the vacuum side of the dielectric window is large, and the temperature distribution is uneven, showing a trend of the highest temperature in the center and gradually decreasing toward the edge. The dielectric window will also be subjected to downward vacuum force and internal stress, causing the dielectric window to sag downward. Among them, the degree of depression in the center of the dielectric window is the largest and gradually decreases toward the edge. When the degree of depression increases, the suspended particles, damaged layer and other parts of the vacuum side surface of the dielectric window may fall off, which may cause the number of particles in the semiconductor process chamber to fail to meet the standard. The dielectric window provided by the implementation of the present application can be used to solve this technical problem.
[0028] refer to Figure 1The bottom surface 111 of the dielectric window 110 provided in the embodiment of the present application has a concave area 1111. The surface of the concave area 1111 is concave toward the top surface 112 of the dielectric window 110. The concave area 1111 is located in the center of the bottom surface 111 of the dielectric window 110.
[0029] In this way, in the embodiment of the present application, by providing the concave area 1111 in the central area of the bottom surface 111 of the dielectric window 110, an effect similar to an "arch bridge" can be achieved, which can reduce the deformation of the bottom surface 111 of the dielectric window 110 and reduce the possibility of the particles deposited on the bottom surface 111 of the dielectric window 110 being peeled off. In addition, the number of particles generated by the dielectric window during the operation of the semiconductor process chamber can be reduced.
[0030] In some embodiments, the surface of the concave area 1111 is a surface of revolution, the axis of the surface of revolution extends along the thickness direction of the dielectric window 110, the generatrix of the surface of revolution is a straight line, the generatrix is coplanar with the axis, and the angle between the generatrix and the axis is less than 90 degrees.
[0031] For example, the surface of the concave area 1111 may be a portion of a conical surface. Figure 1 , a vent may be provided at the center of the dielectric window 110, and the process gas may be transported into the semiconductor process chamber through the vent. In the case where a vent is provided at the center of the dielectric window 110, the vent will form a hollowed-out area, thereby causing the top of the cone surface to be "removed". In other words, the shape of the surface of the concave area 1111 is the same as the shape of the circumferential side wall of the truncated cone. Of course, by way of example, if the vent is provided at other positions, the surface of the concave area 1111 may be a conical surface.
[0032] In the embodiment of the present application, the top surface 112 of the dielectric window 110 may be a plane. Of course, those skilled in the art may also flexibly adjust the shape of the top surface 112 of the dielectric window 110 according to process requirements. Therefore, the embodiment of the present application does not limit the shape of the top surface 112 of the dielectric window 110.
[0033] Exemplarily, the appearance thickness of the dielectric window 110 is generally 20 to 50 mm. Generally speaking, the dielectric window 110 is generally cylindrical in appearance, and the diameter of the dielectric window 110 is generally 350 to 500 mm. In the case where a vent hole is provided at the center of the dielectric window 110, the diameter of the vent hole is generally 5 to 30 mm. Of course, those skilled in the art can also flexibly adjust the size of the dielectric window 110 according to process requirements. In addition, the material and manufacturing process of the dielectric window 110 can refer to the relevant technology, and the embodiments of the present application will not be described in detail.
[0034] In some embodiments, when the surface of the concave region 1111 is a surface of revolution, the axis of the surface of revolution may pass through the center of the bottom surface 111. In other words, the surface of revolution may be disposed at the center of the bottom surface 111 of the dielectric window 110, so that during the operation of the semiconductor process chamber, the bottom surface 111 of the dielectric window 110 can be deformed more uniformly.
[0035] In some embodiments, in some embodiments, the angle between the generatrix of the rotating surface and the axis of the rotating surface is greater than or equal to 85 degrees. A target intersection is formed between the extension line of the generatrix and the axis, and a target endpoint is provided on the side of the generatrix away from the target intersection. In a direction parallel to the axis, the distance between the target intersection and the target endpoint is 1 to 4 mm, that is, the height range of the cone formed by the concave area 1111 is 1 to 4 mm. In a direction perpendicular to the axis, the distance between the target endpoint and the axis is 133.5 to 320 mm, that is, the bottom radius of the cone formed by the concave area 1111 is 133.5 to 320 mm. Of course, in other embodiments, those skilled in the art can also flexibly adjust the various dimensional parameters of the dielectric window 110 according to actual process requirements.
[0036] In some embodiments, the bottom surface 111 of the dielectric window 110 has an edge region 1112, and the surface of the edge region 1112 is horizontally arranged. In some embodiments, the area between the edge region 1112 and the concave region 1111 of the bottom surface 111 of the dielectric window 110 is a transition region 1113, and the surface of the transition region 1113 is an arc-shaped surface. In this way, the concave region 1111 and the edge region 1112 can be transitioned through the transition region 1113, and stress concentration can be avoided.
[0037] It should be noted that, by way of example, in some embodiments, the dielectric window may be 40 mm thick and 450 mm in diameter. The concave area 1111 is a conical surface, the height of the conical surface is 1 to 4 mm, and the angle of inclination of the hypotenuse of the conical surface with the vertical direction is greater than 85 degrees. When the overall thickness of the dielectric window increases and the temperature decreases, the height of the conical surface may be appropriately reduced. When the overall thickness of the dielectric window decreases and the temperature increases, the height of the conical surface may need to be appropriately increased.
[0038] Combination Figure 2 , the dielectric window is approximately Figure 2The shape shown. The dielectric window is mainly subjected to downward force, and the stress on the dielectric window decays rapidly from the edge to the inside. When the structure of the bottom surface of the dielectric window is different, there are differences in the force on the bottom surface of the dielectric window. The stress on each point on the bottom surface of the dielectric window can be calculated by the formula: σ=(qKD) / (2δ), where σ is stress, q is the resultant force, K is the corresponding coefficient, D is the diameter of the point, and δ is the wall thickness of the point. When the concave area of the bottom surface of the dielectric window is a cone, K=1 / cosα, σ=(qD) / (2δcosα), from the center to the edge, D increases, α increases, cosα decreases, and δ increases. Since the overall height of the cone surface ranges from 1 to 4 mm, the increase in δ is less than that of D, so the stress gradually increases from the center to the edge. If the bottom surface of the dielectric window is a plane, the force at the center is the largest and gradually decreases toward the edge. When the concave area on the bottom surface of the dielectric window is a conical surface, the force on the middle part is reduced compared to when the bottom surface of the dielectric window is a plane, and the force decreases from the edge to the center. In one embodiment of the present application, it is considered to set the concave area on the bottom surface of the dielectric window as a conical surface.
[0039] In addition, the inventor of the present application conducted a simulation analysis on the dielectric window. According to the simulation analysis, when the height of the conical surface is a single variable, as the height of the conical surface increases, the dielectric window stress and minimum deformation show a trend of first decreasing and then increasing. When the height of the conical surface is 2 mm, the deformation decreases by about 45%. When the height of the conical surface ranges from 1 to 4 mm, the deformation decreases. When the angle between the hypotenuse of the conical surface and the vertical direction is a single variable, and the edge arc is tangent to the cone, as the angle between the hypotenuse of the conical surface and the vertical direction decreases, the dielectric window stress and minimum deformation show a trend of gradually decreasing. When the angle between the hypotenuse of the conical surface and the vertical direction is 85 degrees, the arc tangency reaches the limit, and the deformation decreases by about 20%. Therefore, it is recommended that the angle between the hypotenuse of the conical surface and the vertical direction is greater than 85 degrees.
[0040] Through simulation analysis and optimization, in one embodiment, the height of the conical surface is 2 mm, the angle between the hypotenuse of the conical surface and the vertical direction is 85 degrees, and the deformation of the dielectric window is minimized. However, when the height of the conical surface ranges from 1 to 4 mm and the angle between the hypotenuse of the conical surface and the vertical direction is greater than 85 degrees, the deformation of the dielectric window is reduced. Compared with the dielectric window with a flat bottom surface, the optimized structure has the same overall thickness and a thinner center thickness, which promotes the transmission of radio frequency energy. At the same time, the surface of the dielectric window has not undergone special surface treatment, the cost is low, and it is not easy to be damaged during maintenance. Comparing the deformation of the two, the deformation of the optimized structure is reduced by about 60%, which can effectively reduce the number of particles falling.
[0041] It should be noted that, when the deformation requirement for the dielectric window is not strict, by way of example, it is also possible to consider setting the concave area of the bottom surface of the dielectric window to a spherical shape, or other shapes, which are not listed here one by one.
[0042] The present application embodiment provides a semiconductor process chamber. Figure 3 , the embodiment of the present application provides a semiconductor process chamber 100 which may include any one of the dielectric windows 110 provided in the embodiment of the present application.
[0043] In some embodiments, the semiconductor process chamber 100 is provided with a reaction chamber 120, the dielectric window 110 is sealed above the reaction chamber 120, and the concave area 1111 faces the reaction chamber 120. The semiconductor process chamber 100 may further include an upper electrode 130 and a lower electrode 140, the upper electrode 130 is arranged above the dielectric window 110, the lower electrode 140 is arranged below the dielectric window 110, a wafer carrying surface 141 is arranged on the top of the lower electrode 140, and the concave area 1111 faces the wafer carrying surface 141. The semiconductor process chamber 100 also includes a cavity 150 and a heater 160. It should be noted that the specific structure of the semiconductor process chamber 100 can be set with reference to relevant technologies or existing technologies, and will not be described in detail here.
[0044] It should be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device.
[0045] Although the embodiments of the present application have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the embodiments of the present application, and the scope of the embodiments of the present application is defined by the appended claims and their equivalents.
Claims
1. A dielectric window (110), applied to a semiconductor process chamber (100), characterized in that: The bottom surface (111) of the dielectric window (110) has a concave area (1111), the surface of the concave area (1111) is concave in a direction close to the top surface (112) of the dielectric window (110), and the concave area (1111) is located in a central area of the bottom surface (111) of the dielectric window (110); The surface of the concave area (1111) is a part of a conical surface, and a vent hole is provided at the center of the dielectric window (110), and the vent hole forms a hollow area at the top of the conical surface.
2. The dielectric window (110) according to claim 1, characterized in that: The surface of the concave area (1111) is a surface of revolution, the axis of the surface of revolution extends along the thickness direction of the dielectric window (110), the generatrix of the surface of revolution is a straight line, the generatrix is coplanar with the axis, and the angle between the generatrix and the axis is less than 90 degrees.
3. The dielectric window (110) according to claim 2, characterized in that: The axis passes through the center of the bottom surface (111).
4. The dielectric window (110) according to claim 2, characterized in that: The included angle between the busbar and the axis is greater than or equal to 85 degrees.
5. The dielectric window (110) according to claim 2, characterized in that: A target intersection is formed between the extension line of the busbar and the axis, and a target endpoint is formed on the side of the busbar away from the target intersection. In a direction parallel to the axis, the distance between the target intersection and the target endpoint is 1 to 4 mm, and in a direction perpendicular to the axis, the distance between the target endpoint and the axis is 133.5 to 320 mm.
6. The dielectric window (110) according to claim 1, characterized in that: The bottom surface (111) of the dielectric window (110) has an edge region (1112), and the surface of the edge region (1112) is arranged horizontally.
7. The dielectric window (110) according to claim 6, characterized in that: The area of the bottom surface (111) of the dielectric window (110) between the edge area (1112) and the concave area (1111) is a transition area (1113), and the surface of the transition area (1113) is an arc-shaped surface.
8. A semiconductor process chamber (100), characterized in that: The dielectric window (110) comprises the dielectric window (110) as claimed in any one of claims 1 to 7.
9. The semiconductor process chamber (100) according to claim 8, characterized in that: The semiconductor process chamber (100) is provided with a reaction chamber (120), the dielectric window (110) is sealed above the reaction chamber (120), and the concave area (1111) faces the reaction chamber (120).
10. The semiconductor process chamber (100) according to claim 9, characterized in that: The semiconductor process chamber (100) further comprises an upper electrode (130) and a lower electrode (140), wherein the upper electrode (130) is arranged above the dielectric window (110), and the lower electrode (140) is arranged below the dielectric window (110), a wafer carrying surface (141) is provided on the top of the lower electrode (140), and the concave area (1111) faces the wafer carrying surface (141).