Apparatus and method for controlling wafer strain compensation along the X / Y direction
Patent Information
- Application Number
- JP2025569926
- Authority / Receiving Office
- JP · JP
- Patent Type
- Applications
- Current Assignee / Owner
- Priority Date
- 2023-07-27
- Filing Date
- 2024-05-30
- Publication Date
- 2026-06-11
AI Technical Summary
【0005】 いくつかの実施形態では、基板は、前面に部分的に製造された集積回路を有する半導体ウェハである。いくつかの実施形態では、基板はサドル形状の反りを有する。いくつかの実施形態では、本方法は、第1の裏面層を形成する前に、第1の反りの大きさが第2の反りよりも大きいと判定するステップをさらに含む。いくつかの実施形態では、本方法は、第1の裏面層を形成する前に、第1の反りの大きさが第2の反りの大きさよりも大きいという判定に基づいて、基板を回転させるステップをさらに含む。いくつかの実施形態では、第1の不均一な厚さプロファイルは、基板のエッジよりも基板の中心に向かってより厚い湾曲バーである。いくつかの実施形態では、湾曲バーは、y方向に実質的に平行な長手方向軸を有する。いくつかの実施形態では、湾曲バーは、x方向およびy方向に垂直で、x方向の関数として基板の裏面から離れる、z方向に厚さが変化する略放物線形状を有する。いくつかの実施形態では、第2の不均一な厚さプロファイルは、基板の中心よりも基板のエッジに向かってより厚い湾曲チャネルである。いくつかの実施形態では、湾曲チャネルは、x方向の関数として基板の裏面から離れる、z方向に厚さが変化する放物線形状を有する。いくつかの実施形態では、第1のタイプの内部応力は引張応力である。いくつかの実施形態では、第1のタイプの内部応力は圧縮応力である。いくつかの実施形態では、基板の裏面上に第3の裏面層を形成するステップをさらに含み、第3の裏面層は、均一な形状、および第1または第2のタイプの内部応力のいずれかを有する。いくつかの実施形態では、第3の裏面層の内部応力のタイプおよび内部応力の大きさは、第1の裏面層および第2の裏面層を形成した後の基板の反りに基づく。いくつかの実施形態では、第1の反りの値および第2の反りの値を識別するステップをさらに含み、第1の裏面層を形成することおよび第2の裏面層を形成するステップは、第1の反りの値および第2の反りの値に基づく。いくつかの実施形態では、第1の反りの値および第2の反りの値を識別するステップをさらに含み、第1の裏面層の内部応力の大きさおよび第2の裏面層の内部応力の大きさは、第1の反りの値および第2の反りの値に基づく。いくつかの実施形態では、1つまたは複数のサイクルは、2つ以上のサイクルである。いくつかの実施形態では、1つまたは複数のサイクル中に堆積される層の総厚は、少なくとも約2μmである。いくつかの実施形態では、第1の裏面層および第2の裏面層は、全体で第1の厚さを有し、(a)および(b)の各サイクルは、第1の厚さを有する相補的プロファイル層を堆積させる。いくつかの実施形態では、第1の厚さは約1μm未満である。いくつかの実施形態では、第1の裏面層および第2の裏面層は、アニール後に約20%未満のウェハ反り補償の変化を示す。いくつかの実施形態では、本方法は、1つまたは複数のサイクルを実行した後、基板の裏面上に第3の裏面層を形成するステップをさらに含み、第3の裏面層は、基板の裏面の平坦度を増加させる。いくつかの実施形態では、第1の裏面層を形成した後にプラズマ処理を実行するステップ、第2の裏面層を形成した後にプラズマ処理を実行するステップ、またはその両方をさらに含み、プラズマ処理は裏面層の接着を改善する。
Smart Images
Figure 2026519111000001_ABST
Abstract
Claims
1. A method for reducing the warping of a substrate, wherein the method is A step of receiving a substrate having a front and a back surface, wherein the substrate has a first curvature in the x-direction and a second curvature in the y-direction; (a) A step of forming a first back layer on the back surface of the substrate, wherein the first back layer compensates for the first warp more than it compensates for the second warp, or compensates for the second warp more than it compensates for the first warp, and the first back layer has a first type of internal stress and a first non-uniform thickness profile, (b) A step of forming a second back layer on the back surface of the substrate, wherein the second back layer compensates for either the first or second warpage which is less compensated by the first back layer, and the second back layer has a second type of internal stress opposite to the first type of internal stress, and a second non-uniform thickness profile, The steps include performing one or more cycles of the following: Includes, When the first back layer and the second back layer are formed, the first non-uniform thickness profile and the second non-uniform thickness profile complement each other so as to provide a complementary film stack having substantially flat surfaces on the back surface of the substrate. method.
2. The method according to claim 1, wherein the substrate is a semiconductor wafer having an integrated circuit partially manufactured on the front surface.
3. The method according to claim 1, wherein the substrate has a saddle-shaped curvature.
4. The method according to claim 1, further comprising the step of determining that the magnitude of the first curvature is greater than the magnitude of the second curvature before forming the first back surface layer.
5. The method according to claim 4, further comprising the step of rotating the substrate based on the determination that the magnitude of the first warp is greater than the magnitude of the second warp, before forming the first back surface layer.
6. The method according to claim 1, wherein the first non-uniform thickness profile is a curved bar that is thicker towards the center of the substrate than at the edges of the substrate.
7. The method according to claim 6, wherein the curved bar has a longitudinal axis substantially parallel to the y-direction.
8. The method according to claim 6, wherein the curved bar has a substantially parabolic shape, perpendicular to the x and y directions, and moving away from the back surface of the substrate as a function of the x direction, with a thickness that changes in the z direction.
9. The method according to claim 1, wherein the second non-uniform thickness profile is a curved channel that is thicker towards the edge of the substrate than towards the center of the substrate.
10. The method according to claim 9, wherein the curved channel has a parabolic shape with a thickness that changes in the z direction, and moves away from the back surface of the substrate as a function of the x direction.
11. The method according to claim 1, wherein the first type of internal stress is a tensile stress.
12. The method according to claim 1, wherein the first type of internal stress is compressive stress.
13. The method according to claim 1, further comprising the step of forming a third back layer on the back surface of the substrate, wherein the third back layer has a uniform shape and either the first type or the second type of internal stress.
14. The method according to claim 13, wherein the type and magnitude of the internal stress of the third back layer are based on the warping of the substrate after the first back layer and the second back layer are formed.
15. The method according to claim 1, further comprising the step of identifying the first curvature value and the second curvature value, wherein the step of forming the first back layer and the step of forming the second back layer are based on the first curvature value and the second curvature value.
16. The method according to claim 1, further comprising the step of identifying the first warp value and the second warp value, wherein the magnitude of the internal stress in the first back layer and the magnitude of the internal stress in the second back layer are based on the first warp value and the second warp value.
17. The method according to claim 1, wherein the one or more cycles are two or more cycles.
18. The method according to claim 1, wherein the total thickness of the layers deposited during one or more cycles is at least about 2 μm.
19. The method according to claim 1, wherein the first back layer and the second back layer have a first thickness in total, and each cycle of (a) and (b) deposits complementary profile layers having the first thickness.
20. The method according to claim 19, wherein the first thickness is less than approximately 1 μm.
21. The method according to claim 1, wherein the first back layer and the second back layer exhibit a change in wafer warpage compensation of less than about 20% after annealing.
22. The method according to claim 1, further comprising the step of forming a third back layer on the back surface of the substrate after performing one or more of the cycles, wherein the third back layer increases the flatness of the back surface of the substrate.
23. The method according to claim 1, further comprising the steps of performing a plasma treatment after forming the first back surface layer, performing a plasma treatment after forming the second back surface layer, or both, wherein the plasma treatment improves the adhesion of the back surface layers.
24. It is a substrate, One or more front layers on the front surface of the substrate, wherein the substrate has a first curvature in the x-direction and a second curvature in the y-direction, A first back layer on the back surface of the substrate, wherein the first back layer compensates for the first warp more than it compensates for the second warp, or compensates for the second warp more than it compensates for the first warp, and the first back layer has a first type of internal stress and a first non-uniform thickness profile, A second back layer on the back surface of the substrate, wherein the second back layer compensates for either the first or second warpage which is less compensated by the first back layer, and the second back layer has a second type of internal stress opposite to the first type of internal stress, and a second non-uniform thickness profile. Includes, When the first back layer and the second back layer are formed, the first non-uniform thickness profile and the second non-uniform thickness profile complement each other so as to provide a complementary film stack having substantially flat surfaces on the back surface of the substrate. substrate.
25. The substrate according to claim 24, wherein if the one or more front layers are not compensated by the first back layer, the substrate has a first or second warp of about 300 μm or more.
26. The substrate according to claim 24, wherein the first non-uniform thickness profile is a curved bar that is thicker toward the center of the substrate than toward the edges of the substrate.
27. The substrate according to claim 26, wherein the curved bar has a longitudinal axis substantially parallel to the y-direction.
28. The substrate according to claim 26, wherein the curved bar has a substantially parabolic shape, perpendicular to the x and y directions, and moving away from the back surface of the substrate as a function of the x direction, with a thickness that changes in the z direction.
29. The substrate according to claim 24, wherein the second non-uniform thickness profile is a curved channel that is thicker toward the edge of the substrate than toward the center of the substrate.
30. The substrate according to claim 29, wherein the curved channel has a parabolic shape with a thickness that changes in the z direction, and moves away from the back surface of the substrate as a function of the x direction.
31. The substrate according to claim 24, wherein the internal stress of the first type is tensile stress.
32. The substrate according to claim 24, wherein the internal stress of the first type is compressive stress.
33. The substrate according to claim 24, further comprising a third back surface layer on the back surface of the substrate, wherein the third back surface layer has a uniform shape and either the first or second type of internal stress.
34. The substrate according to claim 33, wherein the type and magnitude of the internal stress of the third back layer are based on the warping of the substrate after the first back layer and the second back layer are formed.
35. The substrate according to claim 24, further comprising an additional complementary film stack.
36. The substrate according to claim 35, wherein both the complementary film stack and the additional complementary film stack alternate between the first back layer and the second back layer.
37. The substrate according to claim 35, wherein the total thickness of all complementary film stacks is at least about 2 μm.
38. The substrate according to claim 35, wherein the thickness of each complementary film stack is less than approximately 1 μm.
39. The substrate according to claim 35, wherein the change in the total wafer warpage compensation of all the complementary film stacks after annealing is less than about 20%.
40. The substrate according to claim 35, further comprising a third back layer on the back surface of the substrate deposited after all of the complementary film stacks, wherein the third back layer increases the flatness of the back surface of the substrate.
41. An apparatus for semiconductor processing, wherein the apparatus is process chamber and A controller comprising memory and a processor, A step of receiving a substrate having a front and a back surface, wherein the substrate has a first curvature in the x-direction and a second curvature in the y-direction; (a) A step of forming a first back layer on the back surface of the substrate, wherein the first back layer compensates for the first warp more than it compensates for the second warp, or compensates for the second warp more than it compensates for the first warp, and the first back layer has a first type of internal stress and a first non-uniform thickness profile, (b) A step of forming a second back layer on the back surface of the substrate, wherein the second back layer compensates for either the first or second warpage which is less compensated by the first back layer, and the second back layer has a second type of internal stress opposite to the first type of internal stress, and a second non-uniform thickness profile, The steps include performing one or more cycles of the following: A controller and Equipped with, When the first back layer and the second back layer are formed, the first non-uniform thickness profile and the second non-uniform thickness profile complement each other so as to provide a complementary film stack having substantially flat surfaces on the back surface of the substrate. Device.