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US4054497A
Expired / Lapsed
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Method for electrolytically etching semiconductor material
Assignee: Honeywell Inc
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Filing: 1976-09-29
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Granted: 1977-10-18
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Expires: 1996-09-29
Abstract
Abstract A method of etching a submerged semiconductor material structure in which an electrically connected metal mask is utilized to electrolytically etch a semiconductive substrate without damaging the remainder of the structure.
Inventors
- 👤 James F. Marshall
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 15:33
CPC Classifications
H; H04; H04R; H04R23/00; H04R23/006; G; G01; G01L; G01L9/00; G01L9/0041; G01L9/0042; H10; H10D; H10D48/00; H10D48/50
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
155 words
An electrolytic etching method for semiconductor material structure having more than one type of semiconductor material conductivity therein, said method comprising: providing a semiconductor material structure having a first region of a first conductivity type, except in selected regions thereof, which is in a substantially crystalline relationship with a second region of a second conductivity type, said first region being in two strata of two different conductivities, a first strata of a lower conductivity which adjoins said second region and a second strata of a relatively higher conductivity which adjoins said first strata without adjoining said second region, said second strata having one or more said selected regions contained completely therein which are of said second conductivity type, providing a metal etching mask on said second region, and etching electrolytically said semiconductor material structure by electrically contacting said metal etching mask and placing said semiconductor material structure as masked and contacted in an electrolyte bath.
Claim 2
Dependent Claim
155 words
An electrolytic etching method for semiconductor material structure having more than one type of semiconductor material conductivity therein, said method comprising: providing a semiconductor material structure having a first region of a first conductivity type, except in selected regions thereof, which is in a substantially crystalline relationship with a second region of a second conductivity type, said first region being in two strata of two different conductivities, a first strata of a lower conductivity which adjoins said second region and a second strata of a relatively higher conductivity which adjoins said first strata without adjoining said second region, said second strata having one or more said selected regions contained completely therein which are of said second conductivity type, providing a metal etching mask on said second region, and etching electrolytically said semiconductor material structure by electrically contacting said metal etching mask and placing said semiconductor material structure as masked and contacted in an electrolyte bath.
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) | 1980-10-17 | 1981-04-18 | 1981-10-18 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1984-10-17 | 1985-04-18 | 1985-10-18 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1988-10-17 | 1989-04-18 | 1989-10-18 | $7700.00 | Window Closed / Lapsed |