US4297162A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Plasma etching using improved electrode
Assignee: Texas Instruments Inc
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Filing: 1979-10-17
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Granted: 1981-10-27
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Expires: 1999-10-17
Abstract
Abstract Radio frequency plasma etching of conductive coatings on semiconductor slices is improved by the use of a curved electrode which is closer to the slice at the center than at the periphery. Preferably, the electrode is in a symmetrical chamber which contains only one slice, and reactant gases are admitted through apertures in the electrode. An r.f. power source is connected between the electrode and a holder for the slice.
Inventors
- 👤 Randall S. Mundt
- 👤 Timothy A. Wooldridge
- 👤 Thomas O. Blasingame
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 22:02
CPC Classifications
H; H01; H01J; H01J37/00; H01J37/32; H01J37/32431; H01J37/32623; C; C23; C23F; C23F4/00; H01J37/3244; H01J37/32532; H01J37/32541; H05; H05H; H05H1/00; H05H1/24; H05H1/26; H05H1/32; H05H1/34; H05H1/40; Y; Y10; Y10S; Y10S422/00; Y10S422/906
Claims Analysis
Total Claims: 17
Claim 1
Independent Claim
83 words
A radio frequency plasma reactor electrode for treating a relatively flat workpiece surface comprising an electrode surface generally of the same size or greater in size than the workpiece surface, the electrode surface positioned facing said workpiece surface but spaced therefrom to provide a plasma zone, the electrode surface being convex shaped to include a protruding portion which is generally symmetrical about a central area of said workpiece surface and closer to said central area than to peripheral areas of said workpiece surface.
Claim 2
Dependent Claim
83 words
A radio frequency plasma reactor electrode for treating a relatively flat workpiece surface comprising an electrode surface generally of the same size or greater in size than the workpiece surface, the electrode surface positioned facing said workpiece surface but spaced therefrom to provide a plasma zone, the electrode surface being convex shaped to include a protruding portion which is generally symmetrical about a central area of said workpiece surface and closer to said central area than to peripheral areas of said workpiece surface.
Claim 3
Dependent Claim
16 words
Apparatus according to claim 1 wherein the workpiece surface is a semiconductor slice having coatings thereon.
Claim 4
Dependent Claim
15 words
Apparatus according to claim 1 wherein said electrode surface is a section of a sphere.
Claim 5
Dependent Claim
13 words
Apparatus according to claim 3 wherein said electrode is generally circular in shape.
Claim 6
Dependent Claim
32 words
Apparatus according to claim 4 wherein the distance which the protruding portion extends toward said central area is about the same as the minimum spacing between the electrode and the workpiece surface.
Claim 7
Dependent Claim
25 words
Apparatus according to claim 5 wherein the workpiece surface is a generally round semiconductor slice having a coating thereon, and the plasma etches said coating.
Claim 8
Dependent Claim
78 words
A radio frequency plasma reactor for etching conductive coatings on semiconductor slices comprising a relatively flat conductive holder for receiving a semiconductor slice, a conductive electrode having a surface facing said holder, means for applying radio frequency voltage across the electrode and the holder to produce a plasma reaction in a space between the electrode and holder, the electrode including a central portion extending closer to the holder at about the center thereof than around the periphery thereof.
Claim 9
Dependent Claim
78 words
A radio frequency plasma reactor for etching conductive coatings on semiconductor slices comprising a relatively flat conductive holder for receiving a semiconductor slice, a conductive electrode having a surface facing said holder, means for applying radio frequency voltage across the electrode and the holder to produce a plasma reaction in a space between the electrode and holder, the electrode including a central portion extending closer to the holder at about the center thereof than around the periphery thereof.
Claim 10
Dependent Claim
16 words
Apparatus according to claim 7 wherein the electrode has a curved curvex surface facing the holder.
Claim 11
Dependent Claim
16 words
Apparatus according to claim 8 wherein the curvex surface is approximately a section of a sphere.
Claim 12
Dependent Claim
17 words
Apparatus according to claim 9 wherein the conductive electrode and the holder are generally circular in shape.
Claim 13
Dependent Claim
19 words
Apparatus according to claim 10 wherein the electrode has a plurality of small apertures for inlet of reaction gases.
Claim 14
Independent Claim
81 words
A method of etching a coating on a generally circular silicon slice comprising (a) positioning the slice symmetrically in a chamber on a conductive holder, (b) positioning an electrode facing the slice in the chamber, the electrode being of generally symmetrical shape with respect to the slice and having a central part closer to the slice than peripheral parts, (c) admitting reaction gas to the chamber while vacuum-pumping the chamber, (d) applying radio frequency voltage between the holder and the electrode.
Claim 15
Independent Claim
81 words
A method of etching a coating on a generally circular silicon slice comprising (a) positioning the slice symmetrically in a chamber on a conductive holder, (b) positioning an electrode facing the slice in the chamber, the electrode being of generally symmetrical shape with respect to the slice and having a central part closer to the slice than peripheral parts, (c) admitting reaction gas to the chamber while vacuum-pumping the chamber, (d) applying radio frequency voltage between the holder and the electrode.
Claim 16
Dependent Claim
23 words
A method according to claim 12 wherein said central part is shaped in a convex manner generally symmetrical with respect to the slice.
Claim 17
Dependent Claim
17 words
A method according to claim 13 wherein said reaction gas is admitted through ports in said electrode.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1984-10-26 | 1985-04-27 | 1985-10-27 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1988-10-26 | 1989-04-27 | 1989-10-27 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1992-10-26 | 1993-04-27 | 1993-10-27 | $7700.00 | Window Closed / Lapsed |