Patent US2360997A successfully refreshed from Google Patents.
Patent US3635773A successfully refreshed from Google Patents.
US3635773A
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US
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Method of manufacturing a semiconductor device comprising a zener diode and semiconductor device manufactured by using this method
Assignee: US Philips Corp
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Filing: 1968-12-13
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Granted: 1972-01-18
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Expires: 1988-12-13
Abstract
Abstract A method for the manufacture of a Zener diode having a breakdown voltage in the range of 2.5 to 6 volts is described. This is obtained by using diffusion processes to form an abrupt PNjunction. The abrupt PN-junction results from out-diffusion of first impurities causing a reversed concentration gradient in a surface layer and in-diffusion of second impurities into that surface layer producing large concentration gradients that are opposite to one another. The method described is especially useful for the incorporation of Zener diodes in monolithic integrated circuits.
Inventors
- 👤 Jacques Thire
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 22:16
CPC Classifications
H; H10; H10P; H10P95/00; H10D; H10D84/00; H10D84/01; H10D84/0112; H10D84/02; H10D84/03; H10D84/038; H10D84/60; H10D84/611; H10D84/613; H10D99/00; Y; Y10; Y10S; Y10S148/00; Y10S148/037; Y10S148/053; Y10S148/085; Y10S148/151; Y10S438/00; Y10S438/983
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
24 words
A method as set forth in claim 1 wherein the abrupt PN-junction is formed where the first and second impurity distributions exceed 1018 atoms/cc.
Claim 2
Dependent Claim
67 words
A method as set forth in claim 1 in the manufacture of a monolithic integrated circuit comprising in addition to the Zener diode further circuit elements, wherein The body portion comprises an epitaxial layer of the opposite conductivity type, and simultaneously with the diffusion of the first impurities to form the first region further first impurities are diffused to form isolation channels to isolate the circuit elements.
Claim 3
Dependent Claim
29 words
A method as set forth in claim 3 wherein the out-diffusion of the first impurities is carried out while simultaneously regions of a further circuit element are being diffused.
Claim 4
Dependent Claim
46 words
A method as set forth in claim 2 wherein part of the surface of the first region is covered during the out-diffusion step to reduce out-diffusion therefrom, and a contact is later made to the said surface part to establish a connection to the first region.
Claim 5
Dependent Claim
23 words
A method as set forth in claim 2 wherein the out-diffusion step is carried out at a temperature of at least 1,000* C.
Claim 6
Dependent Claim
20 words
A method as set forth in claim 2 wherein the out-diffusion step is carried out in a dry oxygen atmosphere.
Claim 7
Dependent Claim
14 words
A method as set forth in claim 6 wherein the first impurities are boron.
References Cited (Backward Citations)
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US3255056A
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Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1975-01-17 | 1975-07-19 | 1976-01-18 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-01-17 | 1979-07-19 | 1980-01-18 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-01-17 | 1983-07-19 | 1984-01-18 | $7700.00 | Window Closed / Lapsed |