US3716422A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method of growing an epitaxial layer by controlling autodoping
Assignee: International Business Machines Corp
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Filing: 1970-03-30
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Granted: 1973-02-13
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Expires: 1990-03-30
Abstract
Abstract Autodoping from a diffused region in a substrate during growth of an epitaxial layer is prevented by growing a thin epitaxial layer over the entire surface of the substrate and then removing the epitaxial layer except for the portion over the diffused region. A second epitaxial layer is then grown over the surface of the substrate and the first epitaxial layer. The first epitaxial layer caps the diffused region to prevent autodoping into the second epitaxial layer during growth thereof over the surface of the substrate not having the diffused region therein.
Inventors
- 👤 D Ing
- 👤 H Pogge
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 03:39
CPC Classifications
H; H10; H10D; H10D1/00; H10D1/40; H10D1/43; H10P; H10P14/00; H10P14/20; H10P14/29; H10P14/2901; H10P14/2902; H10P14/2905; H10P14/34; H10P14/3402; H10P14/3404; H10P14/3411; H10P32/00; H10P32/10; H10P32/15; Y; Y10; Y10S; Y10S148/00; Y10S148/007; Y10S148/026; Y10S148/037; Y10S148/043; Y10S148/05; Y10S148/117; Y10S438/00; Y10S438/914; Y10S438/916
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
165 words
A method of growing an epitaxial layer on a surface of a body of a semiconductor material having a more heavily doped diffused region in the body in communication with the surface of the body so as to limit the incorporation of outdiffused impurities from said diffused region into portions of said epitaxial layer over the non-diffused regions and to permit the formation of the epitaxial layer with a controlled impurity concentration comprising: depositing a thin epitaxial layer over the surface of the body, removing portions of said thin epitaxial layer which are not over said diffused region and which contain autodoped impurities from said diffused region, while at the same time maintaining intact at least the portion of said thin epitaxial layer which covers said diffused region, and depositing a second epitaxial layer over said body said second layer having a controlled impurity concentration by means of being protected by the remaining portions of said first epitaxial layer from outdiffusion from said diffused region.
Claim 2
Independent Claim
165 words
A method of growing an epitaxial layer on a surface of a body of a semiconductor material having a more heavily doped diffused region in the body in communication with the surface of the body so as to limit the incorporation of outdiffused impurities from said diffused region into portions of said epitaxial layer over the non-diffused regions and to permit the formation of the epitaxial layer with a controlled impurity concentration comprising: depositing a thin epitaxial layer over the surface of the body, removing portions of said thin epitaxial layer which are not over said diffused region and which contain autodoped impurities from said diffused region, while at the same time maintaining intact at least the portion of said thin epitaxial layer which covers said diffused region, and depositing a second epitaxial layer over said body said second layer having a controlled impurity concentration by means of being protected by the remaining portions of said first epitaxial layer from outdiffusion from said diffused region.
Claim 3
Dependent Claim
22 words
The process of claim 1 including the additional step of incorporating a diffused region in the second epitaxial layer as a resistor.
Claim 4
Dependent Claim
21 words
The process of claim 1 wherein said first epitaxial layer has a thickness in the range of 0.3 to 1.0 micron.
Claim 5
Independent Claim
102 words
A method of growing an epitaxial layer on the surface of a body of semiconductor material having a more heavily doped diffused region in the body in communication with the surface of the body so as to limit the incorporation of outdiffused impurities from said diffused region into portions of the epitaxial layer over the non-diffused regions and to permit the formation of the epitaxial layer with a controlled impurity concentration comprising: growing a thin epitaxial layer which is coextensive with said diffused region, growing a second epitaxial layer having a controlled impurity concentration over said body and said thin epitaxial layer.
Claim 6
Independent Claim
102 words
A method of growing an epitaxial layer on the surface of a body of semiconductor material having a more heavily doped diffused region in the body in communication with the surface of the body so as to limit the incorporation of outdiffused impurities from said diffused region into portions of the epitaxial layer over the non-diffused regions and to permit the formation of the epitaxial layer with a controlled impurity concentration comprising: growing a thin epitaxial layer which is coextensive with said diffused region, growing a second epitaxial layer having a controlled impurity concentration over said body and said thin epitaxial layer.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-02-13 | 1976-08-14 | 1977-02-13 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-02-13 | 1980-08-14 | 1981-02-13 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-02-13 | 1984-08-14 | 1985-02-13 | $7700.00 | Window Closed / Lapsed |