US4451538A
Expired / Lapsed
US
⏱️ 0.0 years remaining
High hydrogen amorphous silicon
Assignee: Atlantic Richfield Co
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Filing: 1983-05-13
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Granted: 1984-05-29
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Expires: 2003-05-13
Abstract
Abstract Amorphous silicon having a high band gap is formed by glow discharge in an atmosphere containing H 2 and SiH 4 in a ratio of at least approximately 9 to 1. The partial pressure of H 2 and SiH 4 is preferably no more than 1 torr, and the power density of the discharge is preferably no more than 0.08 watts per square centimeter. In the intrinsic form, the material of the present invention has a band gap of approximately 1.95 electron volts (eV). Similar p-type material, formed by adding B 2 H 6 to the gas atmosphere at approximately 500 parts per million (ppm), has a band gap as high as 1.90 eV.
Inventors
- 👤 David P. Tanner
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 22:45
CPC Classifications
H; H10; H10F; H10F10/00; H10F10/10; H10F10/17; H10F10/172; C; C23; C23C; C23C16/00; C23C16/22; C23C16/24; H10F71/00; H10F71/10; H10F71/103; H10P; H10P14/00; H10P14/20; H10P14/24; H10P14/29; H10P14/2901; H10P14/2922; H10P14/34; H10P14/3402; H10P14/3404; H10P14/3411; H10P14/3438; H10P14/3441; H10P14/3444; Y; Y02; Y02E; Y02E10/00; Y02E10/50; Y02E10/548; Y02P; Y02P70/00; Y02P70/50; Y10; Y10T; Y10T428/00; Y10T428/31504; Y10T428/31652; Y10T428/31663
Claims Analysis
Total Claims: 15
Claim 1
Independent Claim
84 words
A process of forming amorphous silicon from a glow discharge comprising the steps of: providing a gas atmosphere containing H 2 and SiH 4 in a ratio of at least approximately 9 to 1, at a flow rate of no more than 10 -3 SCCM per cubic centimeter; establishing a glow discharge by discharging electrical power through the atmosphere at a density of no more than 0.08 watts per square centimeter; and exposing a substrate to the glow discharge to deposit amorphous Si:H thereon.
Claim 2
Dependent Claim
84 words
A process of forming amorphous silicon from a glow discharge comprising the steps of: providing a gas atmosphere containing H 2 and SiH 4 in a ratio of at least approximately 9 to 1, at a flow rate of no more than 10 -3 SCCM per cubic centimeter; establishing a glow discharge by discharging electrical power through the atmosphere at a density of no more than 0.08 watts per square centimeter; and exposing a substrate to the glow discharge to deposit amorphous Si:H thereon.
Claim 3
Dependent Claim
17 words
The process of claim 1 wherein: the pressure of the gas atmosphere is at least 1 torr.
Claim 4
Dependent Claim
19 words
The process of claim 2 wherein: the ratio of H 2 to SiH 4 is approximately 13 to 1.
Claim 5
Dependent Claim
21 words
The process of claim 2 wherein: the flow rate of the gas atmosphere is approximately 4.5×10 -4 SCCM per cubic centimeter.
Claim 6
Dependent Claim
23 words
The process of claim 2 wherein: electrical power is discharged through the atmosphere at a density of approximately 0.03 watts per square centimeter.
Claim 7
Dependent Claim
12 words
The process of claim 5 wherein: the electrical power is rf power.
Claim 8
Dependent Claim
22 words
The process of claim 2 wherein: the pressure of H 2 and SiH 4 in the gas atmosphere is approximately 2 torr.
Claim 9
Dependent Claim
20 words
The product by the process of claim 1 which has an optical gap of at least approximately 1.85 electron volts.
Claim 10
Dependent Claim
68 words
The process of claim 1 wherein: the ratio of H 2 to SiH 4 is approximately 13 to 1; the flow rate of the gas atmosphere is approximately 4.5×10 -4 SCCM per cubic centimeter; electrical power is discharged through the atmosphere at a density of approximately 0.03 watts per square centimeter; and the pressure of H 2 and SiH 4 in the gas atmosphere is approximately 2 torr.
Claim 11
Dependent Claim
20 words
The product by the process of claim 9 which has an optical gap of at least approximately 1.90 electron volts.
Claim 12
Dependent Claim
13 words
The process of claim 1 wherein: the gas atmosphere includes a preselected dopant.
Claim 13
Dependent Claim
14 words
The process of claim 11 wherein: the dopant comprises B 2 H 6 .
Claim 14
Dependent Claim
25 words
The process of claim 12 wherein: the concentration of B 2 H 6 in the gas atmosphere is at least approximately 500 parts per million.
Claim 15
Dependent Claim
31 words
The product by the process of claim 13 which has an optical gap of at least 1.85 electron volts and a dark conductivity of at least approximately 10 -6 inverse ohm-centimeters.
References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1987-05-29 | 1987-11-28 | 1988-05-29 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1991-05-29 | 1991-11-28 | 1992-05-29 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1995-05-29 | 1995-11-28 | 1996-05-29 | $7700.00 | Window Closed / Lapsed |