US4637836A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Profile control of boron implant
Assignee: Intersil Corp
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Filing: 1985-09-23
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Granted: 1987-01-20
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Expires: 2005-09-23
Abstract
Abstract The ion implantation of a silicon structure isolated from a semiconductor substrate by a layer of silicon dioxide with boron ions to render it p type conductive is improved by initially doping the silicon with phosphorus ions. The presence of the phosphorus ions in the silicon prevents the implanted boron ions from rapidly migrating into the silicon dioxide during annealing.
Inventors
- 👤 Doris W. Flatley
- 👤 Sheng T. Hsu
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 21:33
CPC Classifications
H; H10; H10P; H10P30/00; H10P30/20; H10P30/202; H10P30/204; H10D; H10D84/00; H10D84/01; H10D84/0123; H10D84/0126; H10D84/0165; H10D84/0172; H10D84/0181; H10D84/02; H10D84/03; H10D84/038; H10D84/80; H10D84/82; H10D84/83; H10D84/85; H10D84/857; H10P32/00; H10P32/30; H10P32/302; Y; Y10; Y10S; Y10S438/00; Y10S438/914; Y10S438/919
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
86 words
In a process of ion implanting a silicon structure having a thickness of from about 300 nm to about 700 nm overlying a layer of silicon dioxide with a dosage of boron ions of at least about 10 15 ions per square centimeter thereby rendering the structure p type conductive and annealing said implant, the improvement which comprises doping said structure prior to the boron implant with sufficient phosphorus ions to substantially prevent the migration of the boron ions into the silicon dioxide layer during annealing.
Claim 2
Dependent Claim
86 words
In a process of ion implanting a silicon structure having a thickness of from about 300 nm to about 700 nm overlying a layer of silicon dioxide with a dosage of boron ions of at least about 10 15 ions per square centimeter thereby rendering the structure p type conductive and annealing said implant, the improvement which comprises doping said structure prior to the boron implant with sufficient phosphorus ions to substantially prevent the migration of the boron ions into the silicon dioxide layer during annealing.
Claim 3
Dependent Claim
26 words
A process in accordance with claim 1, wherein the silicon structure is doped with phosphorus ions in-situ as it is deposited onto the silicon dioxide layer.
Claim 4
Dependent Claim
18 words
A process in accordance with claim 1, wherein the silicon structure is doped with phosphorus ions by diffusion.
Claim 5
Dependent Claim
19 words
A process in accordance with claim 1, wherein the silicon structure is doped with phosphorus ions by ion implantation.
Claim 6
Dependent Claim
27 words
A process in accordance with claim 1, wherein the implant dosage of boron ions is from about 10 15 to about 10 16 ions per square centimeter.
Claim 7
Dependent Claim
27 words
A process in accordance with claim 4, wherein the implant dosage of phosphorus ions is from about 10 12 to about 10 15 ions per square centimeter.
Claim 8
Dependent Claim
27 words
A process in accordance with claim 6, wherein the implant dosage of phosphorus ions is from about 10 13 to about 10 14 ions per square centimeter.
References Cited (Backward Citations)
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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) | 1990-01-19 | 1990-07-21 | 1991-01-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1994-01-19 | 1994-07-21 | 1995-01-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1998-01-19 | 1998-07-21 | 1999-01-20 | $7700.00 | Window Closed / Lapsed |