Holder for supporting wafers during semiconductor manufacture

• US 20050022746A1
• Filed: 08/02/2004
• Published: 02/03/2005
• Est. Priority Date: 08/01/2003
• Status: Active Grant

• Current Assignee: SGL Carbon AG
• Original Assignee: SGL Carbon, LLC (Sgl Carbon Se)
• Inventors: Moon, Burl, Lampe, Michael
• Granted Patent: US 7,582,166 B2
• Time in Patent Office: Days
• US Class Current: 118/728
• CPC Class Codes: C23C 16/4581 characterised by material of construction or surface finish of the means for supporting the substrate
• CPC Class Codes: C23C 16/4585 Devices at or outside the perimeter of the substrate support, e.g. clamping rings, shrouds
• CPC Class Codes: C30B 25/12 Substrate holders or susceptors
• CPC Class Codes: H01L 21/68735 characterised by edge profile or support profile
• CPC Class Codes: H01L 21/6875 characterised by a plurality of individual support members, e.g. support posts or protrusions
• CPC Class Codes: H01L 21/68771 characterised by supporting more than one semiconductor substrate

Abstract

An improved wafer holder design is described which has manufacturing and performance advantages over present state-of-the-art holders used in various wafer processing applications. The new wafer holder design incorporates a series of short radial grooves. The grooves extend from the base of a circular channel, which runs along the outside diameter of the substrate wafer recess, to a fixed radial location which varies based on wafer size and thickness. The grooves provide a slight overlap with the wafer to facilitate the free exchange of gases beneath the wafer necessary for wafer loading and unloading operations. The short length of the radial grooves make the wafer holder easier to manufacture and offer more robust performance compared to the present state-of-the-art holders.

Claims

1. A wafer holder for holding semiconductor substrate wafers in a chemical vapor deposition system, comprising:

a holder body having a top surface;

a circular wafer recess in the top surface of the holder body, the wafer recess having an outer perimeter and an interior area; and

a plurality of slots arranged in the top surface of the holder body, each beginning adjacent the outer perimeter of the wafer recess and extending toward and terminating in the interior area of the wafer recess.

2. The wafer holder of claim 1, further comprising a circular groove extending around the outer perimeter of the wafer recess.

3. The wafer holder of claim 2, wherein substantially all of the slots extend radially from the circular groove toward the interior area of the wafer recess.

4. The wafer holder of claim 3, wherein the holder body is formed from at least one of the following:

graphite, silicon, silicon nitride, silicon carbide, quartz or aluminum oxide.

5. The wafer holder of claim 3, wherein a surface coating is applied to at least the top surface of the holder body.

6. The wafer holder of claim 5, wherein the surface coating is formed from at least one of the following:

silicon carbide, silicon nitride, pyrolytic graphite, pyrolytic carbon, diamond, aluminum nitride, aluminum oxide, silicon dioxide or tantalum carbide.

7. The wafer holder of claim 3, wherein the wafer recess encompasses a concave surface.

8. The wafer holder of claim 7, wherein the concave surface of the wafer recess is adapted to aid in gas flow beneath a substrate wafer disposed in the wafer recess.

9. The wafer holder of claim 7, wherein the concave surface of the wafer recess is adapted to help maintain a uniform temperature profile across the surface of a substrate wafer disposed in the wafer recess.

10. The wafer holder of claim 3, wherein the number of slots is selected to minimize negative effects on the thermal profile of a substrate wafer disposed in the wafer recess.

11. The wafer holder of claim 3, wherein the number of slots is selected to allow sufficient gas flow beneath the substrate wafer to aid in proper loading and unloading operations.

12. The wafer holder of claim 3, wherein the dimensions of the slots are selected to minimize negative effects on the thermal profile or backside markings of a substrate wafer disposed in the wafer recess.

13. The wafer holder of claim 3, wherein the dimensions of the slots are selected to provide effective gas flow beneath substrate wafers for the purpose of aiding in proper loading and unloading operations.

14. The wafer holder of claim 3, wherein each of the plurality of slots is between 0.030 in. and 1.000 in. in length.

15. The wafer holder of claim 14, wherein each of the plurality of slots is between 0.035 in. and 0.065 in. in length.

16. The wafer holder of claim 3, wherein each of the plurality of slots is between 0.010 in. and 0.030 in. in width.

17. The wafer holder of claim 16, wherein each of the plurality of slots is between 0.015 in. and 0.025 in. in width.

18. The wafer holder of claim 3, wherein each of the plurality of slots is at least 0.001 in. deep.

19. The wafer holder of claim 18, wherein each of the plurality of slots is between 0.004 in. and 0.008 in. deep.

20. The wafer holder of claim 3, wherein the wafer holder is a susceptor.

21. The wafer holder of claim 3, further comprising a circumferential ledge for supporting the edges of a wafer.

22. The wafer holder of claim 21, wherein the plurality of slots are disposed at least partly in the circumferential ledge.

23. The wafer holder of claim 3, wherein the wafer recess is a first wafer recess and the plurality of slots is a first plurality of slots, the wafer holder further comprising:

a second circular wafer recess in the top surface of the holder body adjacent the first circular wafer recess, the wafer recess having an outer perimeter and an interior area; and

a second plurality of slots arranged in the top surface of the holder body, each beginning adjacent the outer perimeter of the second wafer recess and extending toward and terminating in the interior area of the second wafer recess.

24. A wafer holder for holding semiconductor substrate wafers in a chemical vapor deposition system, comprising:

a holder body having a top surface;

a circular wafer recess in the top surface of the holder body, the wafer recess having an outer perimeter and an interior area; and

a plurality of non-intersecting slots arranged in the top surface of the holder body, each beginning adjacent the outer perimeter of the wafer recess and extending toward and terminating in the interior area of the wafer recess.

25. The wafer holder of claim 24, further comprising a circular groove extending around the outer perimeter of the wafer recess.

26. The wafer holder of claim 25, wherein substantially all of the slots extend radially from the circular groove toward the interior area of the wafer recess.

27. The wafer holder of claim 26, wherein the holder body is formed from at least one of the following:

graphite, silicon, silicon nitride, silicon carbide, quartz or aluminum oxide.

28. The wafer holder of claim 26, wherein a surface coating is applied to at least the top surface of the holder body.

29. The wafer holder of claim 28, wherein the surface coating is formed from at least one of the following:

silicon carbide, silicon nitride, pyrolytic graphite, pyrolytic carbon, diamond, aluminum nitride, aluminum oxide, silicon dioxide or tantalum carbide.

30. The wafer holder of claim 26, wherein the wafer recess encompasses a concave surface.

31. The wafer holder of claim 30, wherein the concave surface of the wafer recess is adapted to aid in gas flow beneath a substrate wafer disposed in the wafer recess.

32. The wafer holder of claim 30, wherein the concave surface of the wafer recess is adapted to help maintain a uniform temperature profile across the surface of a substrate wafer disposed in the wafer recess.

33. The wafer holder of claim 26, wherein the number of slots is selected to minimize negative effects on the thermal profile of a substrate wafer disposed in the wafer recess.

34. The wafer holder of claim 26, wherein the number of slots is selected to allow sufficient gas flow beneath the substrate wafer to aid in proper loading and unloading operations.

35. The wafer holder of claim 26, wherein the dimensions of the slots are selected to minimize negative effects on the thermal profile or backside markings of a substrate wafer disposed in the wafer recess.

36. The wafer holder of claim 26, wherein the dimensions of the slots are selected to provide effective gas flow beneath substrate wafers for the purpose of aiding in proper loading and unloading operations.

37. The wafer holder of claim 26, wherein each of the plurality of slots is between 0.030 in. and 1.000 in. in length.

38. The wafer holder of claim 37, wherein each of the plurality of slots is between 0.035 in. and 0.065 in. in length.

39. The wafer holder of claim 26, wherein each of the plurality of slots is between 0.010 in. and 0.030 in. in width.

40. The wafer holder of claim 39, wherein each of the plurality of slots is between 0.015 in. and 0.025 in. in width.

41. The wafer holder of claim 26, wherein each of the plurality of slots is at least 0.001 in. deep.

42. The wafer holder of claim 41, wherein each of the plurality of slots is between 0.004 in. and 0.008 in. deep.

43. The wafer holder of claim 26, wherein the wafer holder is a susceptor.

44. The wafer holder of claim 26, further comprising a circumferential ledge for supporting the edges of a wafer.

45. The wafer holder of claim 44, wherein the plurality of slots are disposed at least partly in the circumferential ledge.

46. The wafer holder of claim 26, wherein the wafer recess is a first wafer recess and the plurality of slots is a first plurality of slots, the wafer holder further comprising:

a second circular wafer recess in the top surface of the holder body adjacent the first circular wafer recess, the wafer recess having an outer perimeter and an interior area; and

a second plurality of slots arranged in the top surface of the holder body, each beginning adjacent the outer perimeter of the second wafer recess and extending toward and terminating in the interior area of the second wafer recess.