US4590091A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Photochemical process for substrate surface preparation
Assignee: Raytheon Co
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Filing: 1984-12-17
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Granted: 1986-05-20
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Expires: 2004-12-17
Abstract
Abstract A substrate having an undesired native oxide layer formed on the surface thereof is treated at a low temperature by exposure to a chosen vapor phase hydrogen-containing precursor in the presence of radiation of a selected wavelength. Upon radiation-inducement, neutral hydrogen species are formed from the precursor and interact with the native oxide to convert the native oxide to a chemically reduced form. By this process, thermal damage and charge damage to the substrate are avoided and the electrical properties of a subsequently formed device are enhanced.
Inventors
- 👤 Harvey N. Rogers, Jr.
- 👤 James T. Hall
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 23:18
CPC Classifications
H; H10; H10P; H10P70/00; H10P70/10; H10P70/12; C; C23; C23C; C23C16/00; C23C16/02; C23C16/0227; C23C16/0236; C23C16/22; C23C16/30; C23C16/40; C23C16/401; C23C16/402; C23C8/00; C23C8/06; H10P50/00; H10P50/20; H10P50/28; H10P50/282; H10P50/283; H10P52/00; H10P95/00; H10P95/70; Y; Y10; Y10S; Y10S438/00; Y10S438/974
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
94 words
A low-temperature, charge-free process for treating a semiconductor substrate having a native oxide layer formed on the surface thereof, comprising exposing said substrate at a temperature within the range of about 30° to 200° C. to a chosen vapor phase hydrogen-containing precursor capable of being dissociated by radiation of a predetermined wavelength in the presence of radiation of said predetermined wavelength to form neutral hydrogen species sufficient to react with said native oxide and convert said native oxide to a chemically reduced form while simultaneously avoiding thermal damage and charge damage to said substrate.
Claim 2
Dependent Claim
94 words
A low-temperature, charge-free process for treating a semiconductor substrate having a native oxide layer formed on the surface thereof, comprising exposing said substrate at a temperature within the range of about 30° to 200° C. to a chosen vapor phase hydrogen-containing precursor capable of being dissociated by radiation of a predetermined wavelength in the presence of radiation of said predetermined wavelength to form neutral hydrogen species sufficient to react with said native oxide and convert said native oxide to a chemically reduced form while simultaneously avoiding thermal damage and charge damage to said substrate.
Claim 3
Dependent Claim
23 words
The process of claim 1 wherein said neutral hydrogen species is selected from the group consisting of atomic hydrogen and excited molecular hydrogen.
Claim 4
Dependent Claim
13 words
The process of claim 1 wherein said chosen hydrogen-containing precursor is molecular hydrogen.
Claim 5
Dependent Claim
15 words
The process of claim 1 wherein said exposing occurs in the presence of a photosensitizer.
Claim 6
Dependent Claim
21 words
The process of claim 4 wherein said photosensitizer comprises mercury vapors and said predetermined wavelength of said radiation is 2537 angstroms.
Claim 7
Dependent Claim
27 words
The process of claim 1 wherein said semiconductor substrate comprises a material selected from the group consisting of mercury cadmium telluride, gallium arsenide, indium phosphide, and germanium.
Claim 8
Dependent Claim
15 words
The process of claim 1 wherein said predetermined wavelength of said radiation is 1109 angstroms.
Claim 9
Dependent Claim
87 words
The process of claim 1 which further includes, after exposing said native oxide layer to said hydrogen species to provide a treated substrate surface, exposing said treated substrate surface in-situ to chosen vapor phase reactants in the presence of radiation of a predetermined wavelength to bring about a reaction between said vapor phase reactants to form a chosen insulator material which deposits on said treated substrate surface to thereby provide a device having enhanced electrical properties at the interface between said substrate surface and said insulator layer.
Claim 10
Dependent Claim
21 words
The process of claim 8 wherein: (a) said substrate comprises mercury cadmium telluride; and (b) said insulator layer comprises silicon dioxide.
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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) | 1989-05-19 | 1989-11-18 | 1990-05-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1993-05-19 | 1993-11-18 | 1994-05-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1997-05-19 | 1997-11-18 | 1998-05-20 | $7700.00 | Window Closed / Lapsed |