US5494523A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Controlling plasma particulates by contouring the plasma sheath using materials of differing RF impedances
Assignee: Applied Materials Inc
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Filing: 1995-02-23
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Granted: 1996-02-27
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Expires: 2015-02-23
Abstract
Abstract A plasma processing apparatus including a wafer supporting pedestal which is designed to reduce particle trapping phenomena. In a region of the pedestal surface which surrounds or abuts the wafer, the pedestal has a permittivity which is substantially equal to or greater than that of the wafer surface. As a result, the sheath boundary is reshaped to reduce particle trapping.
Inventors
- 👤 Robert J. Steger
- 👤 Charles S. Rhoades
- 👤 Anand Gupta
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 10:54
CPC Classifications
H; H01; H01J; H01J37/00; H01J37/32; H01J37/32431
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
125 words
A plasma processing apparatus for processing a wafer surface comprising: a) a vacuum chamber; b) a pedestal including a pedestal cover within said vacuum chamber, said pedestal having a surface for supporting said wafer; and c) an RF electrical source connected between said pedestal surface and said chamber to generate a plasma within said chamber in a region above said wafer surface; wherein, in a region of said pedestal which adjoins an edge of said wafer, said pedestal surface has a permittivity equal to or greater than a permittivity of said wafer surface, and said pedestal cover further comprises a shadow ring which extends above said wafer surface, said shadow ring having a permittivity equal to or greater than said permittivity of said wafer surface.
Claim 2
Dependent Claim
125 words
A plasma processing apparatus for processing a wafer surface comprising: a) a vacuum chamber; b) a pedestal including a pedestal cover within said vacuum chamber, said pedestal having a surface for supporting said wafer; and c) an RF electrical source connected between said pedestal surface and said chamber to generate a plasma within said chamber in a region above said wafer surface; wherein, in a region of said pedestal which adjoins an edge of said wafer, said pedestal surface has a permittivity equal to or greater than a permittivity of said wafer surface, and said pedestal cover further comprises a shadow ring which extends above said wafer surface, said shadow ring having a permittivity equal to or greater than said permittivity of said wafer surface.
Claim 3
Dependent Claim
123 words
A plasma processing apparatus for processing a wafer surface comprising: a) a vacuum chamber; b) a pedestal including a pedestal cover within said vacuum chamber, said pedestal having a surface for supporting said wafer; and c) an RF electrical source connected between said pedestal surface and said chamber to generate a plasma within said chamber in a region above said wafer surface; wherein, in a region of said pedestal which adjoins an edge of said wafer, said pedestal surface has a permittivity equal to or greater than a permittivity of said wafer surface, and said pedestal cover further comprises an epitaxial layer of inert material overlying said pedestal surface having a permittivity equal to or greater than said permittivity of said wafer surface.
Claim 4
Dependent Claim
123 words
A plasma processing apparatus for processing a wafer surface comprising: a) a vacuum chamber; b) a pedestal including a pedestal cover within said vacuum chamber, said pedestal having a surface for supporting said wafer; and c) an RF electrical source connected between said pedestal surface and said chamber to generate a plasma within said chamber in a region above said wafer surface; wherein, in a region of said pedestal which adjoins an edge of said wafer, said pedestal surface has a permittivity equal to or greater than a permittivity of said wafer surface, and said pedestal cover further comprises an epitaxial layer of inert material overlying said pedestal surface having a permittivity equal to or greater than said permittivity of said wafer surface.
Claim 5
Independent Claim
117 words
A method of processing a wafer surface comprising: a) supporting said wafer on a surface of a pedestal including a pedestal cover in a vacuum chamber; and b) applying an RF electrical source between said pedestal surface and said chamber to generate a plasma within said chamber in an area above said wafer surface; wherein, in a region of said pedestal which adjoins an edge of said wafer, said pedestal surface has a permittivity equal to or greater than a permittivity of said wafer surface, and said pedestal cover further comprises a shadow ting which extends above said wafer surface, said shadow ring having a permittivity equal to or greater than said permittivity of said wafer surface.
Claim 6
Independent Claim
117 words
A method of processing a wafer surface comprising: a) supporting said wafer on a surface of a pedestal including a pedestal cover in a vacuum chamber; and b) applying an RF electrical source between said pedestal surface and said chamber to generate a plasma within said chamber in an area above said wafer surface; wherein, in a region of said pedestal which adjoins an edge of said wafer, said pedestal surface has a permittivity equal to or greater than a permittivity of said wafer surface, and said pedestal cover further comprises a shadow ting which extends above said wafer surface, said shadow ring having a permittivity equal to or greater than said permittivity of said wafer surface.
Claim 7
Independent Claim
115 words
A method of processing a wafer surface comprising: a) supporting said wafer on a surface of a pedestal including a pedestal cover in a vacuum chamber; and b) applying an RF electrical source between said pedestal surface and said chamber to generate a plasma within said chamber in an area above said wafer surface; wherein, in a region of said pedestal which adjoins an edge of said wafer, said pedestal surface has a permittivity equal to or greater than a permittivity of said wafer surface, and said pedestal cover further comprises an epitaxial layer of inert material overlying said pedestal surface having a permittivity equal to or greater than said permittivity of said wafer surface.
Claim 8
Independent Claim
115 words
A method of processing a wafer surface comprising: a) supporting said wafer on a surface of a pedestal including a pedestal cover in a vacuum chamber; and b) applying an RF electrical source between said pedestal surface and said chamber to generate a plasma within said chamber in an area above said wafer surface; wherein, in a region of said pedestal which adjoins an edge of said wafer, said pedestal surface has a permittivity equal to or greater than a permittivity of said wafer surface, and said pedestal cover further comprises an epitaxial layer of inert material overlying said pedestal surface having a permittivity equal to or greater than said permittivity of said wafer surface.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1999-02-26 | 1999-08-28 | 2000-02-27 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2003-02-26 | 2003-08-28 | 2004-02-27 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2007-02-26 | 2007-08-28 | 2008-02-27 | $7700.00 | Window Closed / Lapsed |