Patent US4490182A successfully refreshed from Google Patents.
US4490182A
Expired / Lapsed
US
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Semiconductor processing technique for oxygen doping of silicon
Assignee: ITT Inc
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Filing: 1981-09-14
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Granted: 1984-12-25
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Expires: 2001-09-14
Abstract
Abstract A process for isolating a semiconductor device formed in a p-type silicon substrate includes implanting a layer of oxygen ions below the device. The substrate is then heated to 430°-470° C. to activate the silicon/oxygen complexes thus formed and compensate or overcompensate the region thus forming an intrinsic or n-type isolating layer. The technique may be employed for the isolation of DMOS structures.
Inventors
- 👤 Peter D. Scovell
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 17:46
CPC Classifications
H; H10; H10P; H10P30/00; H10P30/20; H10P30/202; H10P30/204; H10D; H10D62/00; H10D62/10; H10D62/17; H10D62/351; H10D62/80; H10D62/83; H10D62/834; H10P30/208; H10P90/00; H10P90/19; H10P90/1904; H10P90/1906; H10P90/1908; H10W; H10W10/00; H10W10/01; H10W10/10; H10W10/181; Y; Y10; Y10S; Y10S148/00; Y10S148/023; Y10S438/00; Y10S438/914; Y10S438/919
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
87 words
A method of forming a conductively isolating intrinsic or n-type region in a p-type doped silicon substrate comprising the steps of: implanting a layer of oxygen ions into a desired region of said substrate at a concentration level substantially corresponding to the doping level of the substrate material; and heating said substrate to a temperature in the range of about 430° C. to about 470° C. for a period of time sufficient to convert said layer into an isolating region having an intrinsic to n-type conductivity level.
Claim 2
Independent Claim
87 words
A method of forming a conductively isolating intrinsic or n-type region in a p-type doped silicon substrate comprising the steps of: implanting a layer of oxygen ions into a desired region of said substrate at a concentration level substantially corresponding to the doping level of the substrate material; and heating said substrate to a temperature in the range of about 430° C. to about 470° C. for a period of time sufficient to convert said layer into an isolating region having an intrinsic to n-type conductivity level.
Claim 3
Dependent Claim
24 words
The method of claim 1 including the step of masking selected areas of the substrate at least during a part of said implanting step.
Claim 4
Dependent Claim
16 words
The method of claim 1 wherein said substrate is substantially oxygen-free prior to said implanting step.
Claim 5
Dependent Claim
41 words
The method of claim 1, wherein said implanting step includes bombarding the substrate with the oxygen ions at an energy of 200 keV to provide a peak oxygen ion concentration of 10 18 cm -3 to a depth of 1 μm.
Claim 6
Independent Claim
107 words
A method of forming a semiconductor structure comprising the steps of: implanting a layer of oxygen ions into a p-type doped silicon substrate at a concentration level substantially corresponding to the doping level of said substrate; forming at least one semiconductor device in said substrate; and thereafter, heating said substrate at a temperature in the range of about 430° C. to about 470° C. to activate the oxygen in said oxygen layer and to at least compensate for the effect of the p-type impurity in said layer whereby said layer is converted to an intrinsic or n-type conductivity region to isolate said at least one semiconductor device.
Claim 7
Independent Claim
107 words
A method of forming a semiconductor structure comprising the steps of: implanting a layer of oxygen ions into a p-type doped silicon substrate at a concentration level substantially corresponding to the doping level of said substrate; forming at least one semiconductor device in said substrate; and thereafter, heating said substrate at a temperature in the range of about 430° C. to about 470° C. to activate the oxygen in said oxygen layer and to at least compensate for the effect of the p-type impurity in said layer whereby said layer is converted to an intrinsic or n-type conductivity region to isolate said at least one semiconductor device.
Claim 8
Dependent Claim
24 words
The method of claim 5 including the step of masking selected areas of the substrate at least during a part of said implanting step.
Claim 9
Dependent Claim
16 words
The method of claim 5 wherein said substrate is substantially oxygen-free prior to said implanting step.
Claim 10
Dependent Claim
40 words
The method of claim 5 wherein said implanting step includes bombarding the substrate with oxygen ions at an energy of 200 keV to provide a peak oxygen ion concentration of 10 18 cm -3 to a depth of 1 micron.
Claim 11
Dependent Claim
16 words
The method of claim 5 wherein said at least one semiconductor device has a DMOS configuration.
Claim 12
Dependent Claim
18 words
The method of claim 5 wherein said at least one semiconductor device is a bipolar or MOS transistor.
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) | 1987-12-25 | 1988-06-25 | 1988-12-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1991-12-25 | 1992-06-25 | 1992-12-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1995-12-25 | 1996-06-25 | 1996-12-25 | $7700.00 | Window Closed / Lapsed |