US4837172A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method for removing impurities existing in semiconductor substrate
Assignee: Panasonic Holdings Corp
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Filing: 1987-07-15
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Granted: 1989-06-06
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Expires: 2007-07-15
Abstract
Abstract A large quantity of oxygen (10 18 cm -3 ) is dissolved in a semiconductor, for example, a silicon crystal substrate. In particular, in the SOI technology for forming a buried oxide film in silicon by oxygen ion implantation, a large quantity of oxygen (up to 10 20 cm -3 ) is left over in the silicon top layer. Such oxygen in the silicon becomes fine precipitates (defects) by the subsequent heat treatment step. Disclosed is, hence, a method for obtaining a semiconductor substrate of high quality by removing impurities by implanting ions containing light element (for example, hydrogen) before heat treatment.
Inventors
- 👤 Bunji Mizuno
- 👤 Masafumi Kubota
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 09:14
CPC Classifications
H; H10; H10P; H10P30/00; H10P30/20; H10P30/202; H10P30/204; H10P30/208; H10P30/225; H10P36/00; H10P36/03; H10P36/07; H10P90/00; H10P90/19; H10P90/1904; H10P90/1906; H10W; H10W10/00; H10W10/01; H10W10/061; H10W10/10; H10W10/181; H10P90/1908; H10W10/011; H10W10/014; H10W10/17
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
104 words
A method for making a silicon-on-insulator (SOI) structure having a buried oxide layer and silicon top layer thereon in a silicon substrate comprising steps of: (a) implanting hydrogen or hydrogen ions into a first region in said silicon substrate, which region is to be said silicon top layer; (b) implanting oxygen or ions which contain oxygen into a second region in said silicon substrate, which region is to be said buried oxide layer, thereby, residual oxygen remaining in said silicon top layer in this step (b); (c) annealing the structure of step (b); and (d) removing said residual oxygen from said silicon top layer.
Claim 2
Independent Claim
104 words
A method for making a silicon-on-insulator (SOI) structure having a buried oxide layer and silicon top layer thereon in a silicon substrate comprising steps of: (a) implanting hydrogen or hydrogen ions into a first region in said silicon substrate, which region is to be said silicon top layer; (b) implanting oxygen or ions which contain oxygen into a second region in said silicon substrate, which region is to be said buried oxide layer, thereby, residual oxygen remaining in said silicon top layer in this step (b); (c) annealing the structure of step (b); and (d) removing said residual oxygen from said silicon top layer.
Claim 3
Independent Claim
104 words
A method for making a silicon-on-insulator (SOI) structure having a buried oxide layer and silicon top layer thereon in a silicon substrate comprising steps of: (a) implanting oxygen or ions which contain oxygen into a second region in said silicon substrate, which region is to be said buried oxide layer, thereby, residual oxygen remaining in said silicon top layer in this step (a); (b) implanting hydrogen or hydrogen ions into a first region in said silicon substrate, which region is to be said silicon top layer; (c) annealing the structure of step (b); and (d) removing said residual oxygen from said silicon top layer.
Claim 4
Independent Claim
104 words
A method for making a silicon-on-insulator (SOI) structure having a buried oxide layer and silicon top layer thereon in a silicon substrate comprising steps of: (a) implanting oxygen or ions which contain oxygen into a second region in said silicon substrate, which region is to be said buried oxide layer, thereby, residual oxygen remaining in said silicon top layer in this step (a); (b) implanting hydrogen or hydrogen ions into a first region in said silicon substrate, which region is to be said silicon top layer; (c) annealing the structure of step (b); and (d) removing said residual oxygen from said silicon top layer.
Claim 5
Dependent Claim
26 words
The method of claim 1, wherein said oxygen or ions which contain oxygen are implanted in the amount of at least 1×10 18 ions/cm 2 .
Claim 6
Dependent Claim
26 words
The method of claim 2, wherein said oxygen or ions which contain oxygen are implanted in the amount of at least 1×10 18 ions/cm 2 .
References Cited (Backward Citations)
US3830668A
Cited
US3865633A
Cited
US4069068A
Cited
JPS5344170A
Cited
JPS5420671A
Cited
US4358323A
Cited
US4579600A
Cited
US4704302A
Cited
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| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
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| 3.5 Years (Year 4) | 1992-06-05 | 1992-12-05 | 1993-06-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1996-06-05 | 1996-12-05 | 1997-06-06 | $3760.00 | Window Closed / Lapsed |
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