Gas distribution plate assembly for providing laminar gas flow across the surface of a substrate

• US 6,537,419 B1
• Filed: 04/26/2000
• Issued: 03/25/2003
• Est. Priority Date: 04/26/2000
• Status: Expired due to Fees

• Current Assignee: Lam Research Corporation
• Original Assignee: Axcelis Technologies Incorporated
• Inventors: Kinnard, David W.
• Primary Examiner(s): Mills, Gregory
• Assistant Examiner(s): HASSANZADEH, PARVIZ
• Application Number:
  US09/558,606
• Time in Patent Office: 1,063 Days
• Field of Search: 118/723.E, 118/715, 118/723.ER, 156/345.47, 156/345.34, 156/345.33
• US Class Current: 156/345.34
• CPC Class Codes: C23C 16/45565 Shower nozzles
• CPC Class Codes: H01J 37/3244 Gas supply means

Abstract

A baffle plate assembly (12) is provided for distributing gas flow into an adjacent process chamber cavity (20) containing a semiconductor wafer to be processed. The baffle plate assembly (12) comprises a generally planar upper baffle plate (14) fixedly positioned above a generally planar lower baffle plate (16) and covered by a process chamber top wall (17). The top wall (17) and the lower baffle plate form a plenum therebetween, the plenum operating at a higher pressure than the process chamber cavity (20) during operation of the device, At least the lower baffle plate (16) has a pattern of apertures (30) formed therein for permitting gas to pass therethrough and into the wafer process chamber. The upper baffle plate (16) and the lower baffle plate (14) are positioned generally parallel to each other, and the upper baffle plate (14) is smaller than the lower baffle plate (16). Preferably, the lower baffle plate (14) is comprised of low-alloy anodized aluminum, and the upper baffle plate (16) is comprised of sapphire-coated quartz.

Claims

1. A plasma processing chamber (10) for processing a semiconductor wafer contained therein, comprising:

(i) a wafer processing cavity (20) into which a wafer may be inserted for processing, the wafer processing cavity defined in part by walls (38) including a top wall (17); and

(ii) a baffle plate assembly (12) located adjacent said wafer processing cavity for distributing energized gas thereinto, said baffle plate assembly comprising a generally planar upper baffle plate (14) fixedly positioned above a generally planar lower baffle plate (16), said upper baffle plate being smaller than said lower baffle plate so as to form a plenum between said top wall (17) and said lower baffle plate (16);

said upper baffle plate (14) being provided with a central portion (62) that is apertureless surrounded by apertures (28) formed therein for permitting gas to pass therethrough to said lower baffle plate;

said plenum operating at a higher pressure than said processing cavity (20) during operation of the chamber (10);

said lower baffle plate (16) having a pattern of apertures (30) formed therein for permitting gas to pass therethrough from said plenum and into said wafer processing cavity.

2. The plasma processing chamber (10) of claim 1, wherein said upper baffle plate (16) and said lower baffle plate (14) are positioned generally parallel to each other and to the wafer being processed in cavity (20).

3. The plasma processing chamber (10) of claim 2, wherein said lower baffle plate (14) is comprised of low-alloy anodized aluminum.

4. The plasma processing chamber (10) of claim 3, wherein said upper baffle plate (16) is comprised of quartz.

5. The plasma processing chamber (10) of claim 4, wherein said upper quartz baffle plate (16) is coated with sapphire.

6. The plasma processing chamber (10) of claim 2, wherein the chamber (10) is adapted to receive a wafer having a diameter of approximately 300 millimeters (mm).

7. The plasma processing chamber (10) of claim 6, wherein said apertures (30) in said lower baffle plate (14) are arranged in a pattern such that each aperture (30) is equidistant from any adjacent aperture.

8. The plasma processing chamber (10) of claim 6, wherein said upper baffle plate apertures (28) are larger in size than said lower baffle plate apertures (30).

9. The plasma processing chamber (10) of claim 8, wherein said upper baffle plate apertures (28) are formed in a concentric multiply circular pattern.

10. The plasma processing chamber (10) of claim 2, wherein the chamber (10) is adapted to receive a wafer having a diameter of approximately 200 millimeters (mm).

11. The plasma processing chamber (10) of claim 10, wherein said apertures (30) in said lower baffle plate (14) are arranged in a concentric multiply circular pattern.

12. A baffle plate assembly (12) for distributing gas flow into an adjacent process chamber containing a semiconductor wafer to be processed, comprising:

a generally planar upper baffle plate (14) fixedly positioned above a generally planar lower baffle plate (16), said upper and lower baffle plates forming an area (66) therebetween;

said upper baffle plate (14) being smaller than said lower baffle plate and being provided with a central portion (62) that is apertureless surrounded by apertures (28) formed therein for permitting gas to pass therethrough to said lower baffle plate;

said lower baffle plate (16) having a pattern of apertures (30) formed therein for permitting gas to pass therethrough and into the wafer process chamber.

13. The baffle plate assembly (12) of claim 12, wherein said upper baffle plate (16) and said lower baffle plate (14) are positioned generally parallel to each other.

14. The baffle plate assembly (12) of claim 13, wherein said lower baffle plate (14) is comprised of low-alloy anodized aluminum.

15. The baffle plate assembly (12) of claim 14, wherein said upper baffle plate (16) is comprised of quartz.

16. The baffle plate assembly (12) of claim 15, wherein said upper quartz baffle plate (16) is coated with sapphire.

17. The baffle plate assembly (12) of claim 13, wherein said apertures (30) in said lower baffle plate (14) are arranged in a pattern such that each aperture (30) is equidistant from any adjacent aperture.

18. The baffle plate assembly (12) of claim 13, wherein said upper baffle plate apertures (28) are larger in size than said lower baffle plate apertures (30).

19. The baffle plate assembly (12) of claim 18, wherein said upper baffle plate apertures (28) are formed in a concentric multiply circular pattern.

20. The baffle plate assembly (12) of claim 13, wherein said apertures (30) in said lower baffle plate (14) are arranged in a concentric multiply circular pattern.