US4224088A
Expired / Lapsed
US
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Method for manufacturing a semiconductor device
Assignee: Toshiba Corp
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Filing: 1978-10-24
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Granted: 1980-09-23
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Expires: 1998-10-24
Abstract
Abstract A method for manufacturing steps of depositing phosphorus onto separate portions of a silicon substrate, covering only one portion with a polycrystalline silicon layer and heating the deposited phosphorus on the separate portions at the same time to diffuse thereby forming two diffusion layers of different depths.
Inventors
- 👤 Shigeru Komatsu
- 👤 Hiroshi Inoue
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 03:42
CPC Classifications
H; H10; H10P; H10P32/00; H10P32/30; H10P32/302; H10D; H10D64/00; H10D64/01; H10D64/011; H10D64/0111; H10D64/0113; H10P32/10; H10P32/14; H10P32/1408; H10P32/1414; H10P32/17; H10P32/171
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
83 words
A method for manufacturing a semiconductor device comprising a first step for preparing a silicon body, a second step for forming first and second n-type regions by depositing phosphorus separately on two portions on said body, a third step for forming a polycrystalline silicon layer on said first n-type region, and a fourth step for heating to diffuse phosphorus within said first and second n-type regions, to form a shallow first diffused region and a deep second diffused region separately in said body.
Claim 2
Independent Claim
83 words
A method for manufacturing a semiconductor device comprising a first step for preparing a silicon body, a second step for forming first and second n-type regions by depositing phosphorus separately on two portions on said body, a third step for forming a polycrystalline silicon layer on said first n-type region, and a fourth step for heating to diffuse phosphorus within said first and second n-type regions, to form a shallow first diffused region and a deep second diffused region separately in said body.
Claim 3
Dependent Claim
33 words
A method according to claim 1, wherein said third step is a process for forming a polycrystalline silicon layer doped with an n-type impurity with a diffusion coefficient smaller than that of phosphorus.
Claim 4
Dependent Claim
58 words
A method according to claim 1 or 2, wherein said first step includes preparing an n-type silicon substrate and forming first and second p-type base regions on one side of said substrate, said two base regions being separated from each other, and said second step includes depositing phosphorus separately on portions on said first and second base regions.
Claim 5
Dependent Claim
20 words
A method according to claim 3, wherein said second step is a process for depositing phosphorus by decomposing phosphorus oxychloride.
Claim 6
Dependent Claim
20 words
A method according to claim 3, wherein said second step is a process for depositing phosphorus ions by ion implantation.
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) | 1983-09-23 | 1984-03-24 | 1984-09-23 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1987-09-23 | 1988-03-24 | 1988-09-23 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1991-09-23 | 1992-03-24 | 1992-09-23 | $7700.00 | Window Closed / Lapsed |