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US3791885A
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Method of manufacturing a semiconductor region
Assignee: Telefunken Electronic GmbH
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Filing: 1971-06-28
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Granted: 1974-02-12
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Expires: 1991-06-28
Abstract
Abstract A method of manufacturing a semiconductor region comprises forming a layer of diffusion material over a diffusion window and a layer of insulating material on a semiconductor body and in which the diffusion window is formed, removing the diffusion material from the insulating layer so as to leave the diffusion material over the diffusion window and diffusing the diffusion material through the diffusion window into the semiconductor body.
Inventors
- 👤 K Merchant
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 11:53
CPC Classifications
H; H10; H10P; H10P95/00; H10D; H10D99/00; H10P32/00; H10P32/10; H10P32/14; H10P32/1408; H10P32/141; H10P32/17; H10P32/171
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
31 words
A method as defined in claim 1, wherein said diffusion material layer is removed by etching using an etching mask having an area larger than the area of said diffusion window.
Claim 2
Dependent Claim
22 words
A method as defined in claim 1, wherein said first diffusion stage occurs simultaneously with the formation of said diffusion material layer.
Claim 3
Dependent Claim
24 words
A method as defined in claim 1, wherein said diffusion material layer is a glass layer formed by vapour diffUsion in an oxidising atmosphere.
Claim 4
Dependent Claim
36 words
A method as defined in claim 1, wherein said semiconductor body includes a base region and wherein an emitter region of a transistor is formed by said diffusion through said diffusion window into the base region.
Claim 5
Dependent Claim
51 words
A method as defined in claim 5, wherein said diffusion material layer is removed by etching using an etching mask whose area is larger than that of said diffusion window so as to cover not only said diffusion window but also a portion of said insulating layer adjacent said diffusion window.
Claim 6
Dependent Claim
77 words
A method as defined in claim 6 wherein a major portion of the surface area of said insulating layer is free of the etching mask so that this area is free of said diffusion material layer subsequent to the etching, and further comprising the step of forming a further window in said area of said insulating layer which is free of said diffusion material layer for providing a contact area for the base region of the transistor.
Claim 7
Dependent Claim
17 words
A method as defined in claim 7, wherein said etching mask is a layer of photo-sensitive lacquer.
Claim 8
Dependent Claim
21 words
A method as defined in claim 8, wherein said diffusion window for said emitter region is used for a phosphorus diffusion.
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) | 1977-02-11 | 1977-08-13 | 1978-02-12 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-02-11 | 1981-08-13 | 1982-02-12 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-02-11 | 1985-08-13 | 1986-02-12 | $7700.00 | Window Closed / Lapsed |