REPLACEABLE UPPER CHAMBER PARTS OF PLASMA PROCESSING APPARATUS

• US 20110056626A1
• Filed: 09/10/2010
• Published: 03/10/2011
• Est. Priority Date: 09/10/2009
• Status: Active Grant

• Current Assignee: Lam Research Corporation
• Original Assignee: Lam Research Corporation
• Inventors: Bogart, Jeff A., Kenworthy, Ian J., Brown, Daniel Arthur
• Granted Patent: US 9,076,634 B2
• Time in Patent Office: Days
• US Class Current: 156/345.33
• CPC Class Codes: C23C 16/45563 Gas nozzles
• CPC Class Codes: C23C 16/45578 Elongated nozzles, tubes with holes
• CPC Class Codes: H01J 37/321 the radio frequency energy being inductively coupled to the plasma
• CPC Class Codes: H01J 37/32119 Windows
• CPC Class Codes: H01J 37/3244 Gas supply means
• CPC Class Codes: H01J 37/32449 Gas control, e.g. control of the gas flow
• CPC Class Codes: H01J 37/32458 Vessel
• CPC Class Codes: H01J 37/32477 characterised by the means for protecting vessels or internal parts, e.g. coatings
• CPC Class Codes: H01J 37/32495 Means for protecting the vessel against plasma
• CPC Class Codes: H01J 37/32513 Sealing means, e.g. sealing between different parts of the vessel
• CPC Class Codes: H01J 37/32522 Temperature

Abstract

An upper chamber section of a plasma reaction chamber includes a ceramic window with blind bores in an upper surface for receipt of a thermal couple and a resistance temperature detector, a top chamber interface which comprises an upper surface which vacuum seals against the bottom of the window and a gas injection system comprising 8 side injectors mounted in the sidewall of the top chamber interface and a gas delivery system comprising tubing which provides symmetric gas flow to the 8 injectors from a single gas feed connection.

Claims

1. A replaceable upper chamber part of a plasma reaction chamber in which semiconductor substrates can be processed, comprising a window, side gas delivery system and/or top chamber interface, wherein:

the top chamber interface comprises a monolithic metal cylinder having a uniform diameter inner surface, an upper flange extending horizontally away from the inner surface and a lower flange extending horizontally away from the inner surface;

an upper annular vacuum sealing surface adapted to seal against a dielectric window of the plasma chamber;

a lower annular vacuum sealing surface adapted to seal against a bottom section of the plasma chamber;

a thermal mass at an upper portion of the cylinder, the thermal mass defined by a wider portion of the cylinder between the inner surface and an outer surface extending vertically from the upper flange, the thermal mass being effective to provide azimuthal temperature uniformity of the inner surface, and a thermal choke at a lower portion of the cylinder effective to minimize transfer of heat across the lower vacuum sealing surface, the thermal choke defined by a thin metal section having a thickness of less than 0.25 inch and extending at least 25% of the length of the inner surface;

the window comprises a ceramic disk having a uniform thickness, at least one blind hole configured to receive a temperature monitoring sensor, a vacuum sealing surface adapted to seal against an upper flange of a top chamber interface, and a central bore configured to receive a top gas injector which delivers process gas into the center of the chamber; and

/or

the gas delivery system comprises bifurcated gas lines which receive tuning gas from a common feed and gas tubes arranged to flow the tuning gas equal distances from the common feed to injectors mounted in a side wall of the top chamber interface.

2. The replaceable upper chamber part of claim 1, wherein the gas delivery system includes eight injectors symmetrically arranged around the top chamber interface and the gas lines can include eight gas lines of which two primary gas lines of equal length extend from the common feed, two secondary gas lines of equal length extend from the outlets of the primary gas lines and four tertiary gas lines of equal length extend from outlets of the secondary gas lines.

3. The replaceable upper chamber part of claim 2, wherein the primary gas lines are longer than the secondary gas lines and the secondary gas lines are longer than the tertiary gas lines, the primary gas lines are connected to midpoints of the secondary gas lines and the secondary gas lines are connected to midpoints of the tertiary gas lines.

4. The replaceable upper chamber part of claim 1, wherein the gas delivery system is designed to fit within a small volume defined by an annular recess in the outer surface of the top chamber interface.

5. The replaceable upper chamber part of claim 1, wherein the outer surface of the top chamber interface includes an annular recess and the gas delivery system is fitted completely within a volume defined by the annular recess.

6. The replaceable upper chamber part of claim 1, wherein the window includes two blind bores in the upper surface, the bores configured to mount temperature sensing probes therein.

7. The replaceable upper chamber part of claim 1, wherein the window includes a central opening, the opening configured to provide a locking engagement with a cylindrical gas injector body having a central gas passage which delivers process gas to an open space in the chamber beneath the window.

8. The replaceable upper chamber part of claim 1, wherein the top chamber interface includes a groove in the upper flange configured to receive an O-ring which provides a vacuum seal between the window and the top chamber interface.

9. The replaceable upper chamber part of claim 1, wherein the window includes a thermally sprayed yttria coating on a lower surface thereof.

10. The replaceable upper chamber part of claim 1, wherein the top chamber interface is anodized aluminum.

11. A ceramic side gas injector configured to mount in any one of eight symmetrically arranged gas injector mounting holes in a side wall of a top chamber interface of a plasma reaction chamber in which semiconductor substrates can be processed, the side gas injector consisting of a stepped cylindrical ceramic body having an upstream section of larger diameter than a downstream section, and a uniform diameter central bore extending in an axial direction through axial end surfaces of the injector body.

12. The gas injector of claim 11, wherein the central bore has a diameter of 0.038 to 0.042 inch and length of 0.52 to 0.53 inch.

13. The gas injector of claim 11, wherein the ceramic body consists entirely of yttria.

14. The gas injector of claim 11, wherein the upstream section is sized to fit in a wider portion of the mounting hole and the downstream section is sized to fit in an opening in a plasma exposed surface of the side wall of the top chamber interface such that a distal end of the injector projects 0.05 to 0.2 inch beyond the plasma exposed surface.

15. The gas injector of claim 11, wherein the ceramic body includes a first washer engaging surface on the axial end surface of the upstream section and a second washer engaging surface extending perpendicularly between the upstream section and the downstream section.

16. The gas injector of claim 11, wherein the central bore has an aspect ratio of 13 to 14.

17. The gas injector of claim 11, wherein the injector body has a length of 0.52 to 0.53 inch, a diameter of 0.2 to 0.3 inch at the upstream section and a diameter of 0.12 to 0.13 inch at the downstream section.

18. The gas injector of claim 11, wherein the upstream section has a length of 0.27 to 0.28 inch and the downstream section has a length of 0.24 to 0.25 inch.