Patent EP0668614A2 successfully refreshed from Google Patents.
EP0668614A2
Expired / Lapsed
EP
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System for improving the total thickness variation of a wafer
Assignee: Raytheon Co
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Filing: 1995-02-01
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Granted: —
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Expires: 2015-02-01
Abstract
Abstract A system for improving the total thickness variation across a surface of a bulk semiconductor wafer includes an initial total thickness variation measuring instrument. The initial total thickness variation profile is then converted to a dwell time versus position map. A confined plasma is then used to selectively locally remove material from the surface so that the final surface of the bulk semiconductor has an improved final total thickness variation.
Inventors
- 👤 L. David Bollinger
- 👤 James F. Nester
- 👤 Charles B. Zarowin
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-03 22:08
CPC Classifications
H; H10; H10P; H10P74/00; H10P74/20; H10P74/203; H10P74/23; H10P74/27
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
93 words
A system for controlling the total thickness variation of a surface of a bulk semiconductor wafer; said system comprising: means for determining an initial total thickness variation profile for said surface of said wafer; means for generating a dwell time versus position map for said surface of said wafer, said map being generated from said initial total thickness variation profile; and means for selectively locally removing material by plasma etching from said surface of said wafer, said selective local material removal means being controlled in accordance with said dwell time versus position map.
Claim 2
Independent Claim
93 words
A system for controlling the total thickness variation of a surface of a bulk semiconductor wafer; said system comprising: means for determining an initial total thickness variation profile for said surface of said wafer; means for generating a dwell time versus position map for said surface of said wafer, said map being generated from said initial total thickness variation profile; and means for selectively locally removing material by plasma etching from said surface of said wafer, said selective local material removal means being controlled in accordance with said dwell time versus position map.
Claim 3
Dependent Claim
28 words
The system as claimed in Claim 1 wherein said initial total thickness variation profile determining means measures said initial total thickness variation on a point by point basis.
Claim 4
Dependent Claim
24 words
The system as claimed in Claim 1 wherein said means for determining the initial total thickness variation profile is a capacitive thickness measuring instrument.
Claim 5
Dependent Claim
27 words
The system as claimed in Claim 1, further comprising: means for delivering one or more bulk semiconductor wafers to said initial total thickness variation profile determining means.
Claim 6
Dependent Claim
26 words
The system as claimed in Claim 1 further comprising: means for transporting one or more bulk semiconductor wafers away from said selectively locally material removal means.
Claim 7
Dependent Claim
52 words
The system as claimed in Claim 1 wherein said generating means includes means for subtracting said initial total thickness variation profile data for preselected total thickness variation profile data on a point by point basis such that said dwell time versus position map represents a surface having said preselected total thickness variation.
Claim 8
Dependent Claim
42 words
The system as claimed in Claim 1 wherein said means for selectively locally removing material includes: means for producing a confined plasma; and means for providing relative motion between said surface of said bulk semiconductor wafer and said confined plasma producing means.
Claim 9
Dependent Claim
21 words
The system as claimed in Claim 7 wherein said confined plasma producing means includes a cavity wherein said plasma in confined.
Claim 10
Dependent Claim
38 words
The system as claimed in Claim 8 wherein said confined plasma producing means further includes: means for supplying a plasma feed gas into said cavity; and means for providing RF power to ignite and maintain said confined plasma.
Claim 11
Independent Claim
29 words
The system as claimed in one of the preceding Claims further including means for determining a final total thickness variation profile for said surface of said bulk semiconducter wafer.
References Cited (Backward Citations)
No citation records indexed.
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