US4372032A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Normally off InP field effect transistor making process
Assignee: United States Department of the Navy
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Filing: 1981-03-30
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Granted: 1983-02-08
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Expires: 2001-03-30
Abstract
Abstract A normally off insulated gate field effect transistor having a p-type sin crystal InP substrate with source and drain contacts spaced apart and disposed thereon with a layer of silicon dioxide disposed over the InP material in the space between the contacts and a gate electrode disposed on the silicon dioxide to completely bridge the space between the contacts. The p-type single crystal InP substrate may be replaced by a p-type epitaxial InP material disposed on a semi-insulating InP substrate.
Inventors
- 👤 David A. Collins
- 👤 Derek L. Lile
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 17:22
CPC Classifications
H; H10; H10D; H10D62/00; H10D62/80; H10D62/85; H10D30/00; H10D30/60
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
72 words
In a method for producing a normally off insulated gate field-effect transistor the steps of: selecting a p-type single crystal indium phosphide substrate; disposing a source contact and a drain contact spaced apart on said substrate; disposing a layer of silicon dioxide over said substrate between said source and drain contacts; and disposing a gate electrode on said layer of silicon dioxide completely bridging the space between said source and drain contacts.
Claim 2
Dependent Claim
72 words
In a method for producing a normally off insulated gate field-effect transistor the steps of: selecting a p-type single crystal indium phosphide substrate; disposing a source contact and a drain contact spaced apart on said substrate; disposing a layer of silicon dioxide over said substrate between said source and drain contacts; and disposing a gate electrode on said layer of silicon dioxide completely bridging the space between said source and drain contacts.
Claim 3
Dependent Claim
29 words
The method of claim 1 further comprising the step of annealing said source and drain contacts to increase resistance to hole conduction and reduce their resistance to electron flow.
Claim 4
Dependent Claim
16 words
The method of claim 2 wherein said contacts are annealed at 325° C. for 15 minutes.
Claim 5
Dependent Claim
84 words
In a method for producing a normally off insulated gate field-effect transistor, the steps of: selecting a semi-insulating indium phosphide substrate; depositing an epitaxial film of p-type semiconducting indium phosphide on said substrate; disposing a source contact and a drain contact spaced apart on said semiconducting material; disposing a layer of silicon dioxide over said semiconducting film between said source and drain contacts and disposing a gate electrode on said layer of silicon dioxide completely bridging the space between said source and drain contacts.
Claim 6
Dependent Claim
84 words
In a method for producing a normally off insulated gate field-effect transistor, the steps of: selecting a semi-insulating indium phosphide substrate; depositing an epitaxial film of p-type semiconducting indium phosphide on said substrate; disposing a source contact and a drain contact spaced apart on said semiconducting material; disposing a layer of silicon dioxide over said semiconducting film between said source and drain contacts and disposing a gate electrode on said layer of silicon dioxide completely bridging the space between said source and drain contacts.
Claim 7
Dependent Claim
29 words
The method of claim 4 further comprising the step of annealing said source and drain contacts to increase resistance to hole conduction and reduce the resistance to electron flow.
Claim 8
Dependent Claim
15 words
The method of claim 5 wherein said contacts are annealed at 325° for 15 minutes.
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) | 1986-02-07 | 1986-08-09 | 1987-02-08 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1990-02-07 | 1990-08-09 | 1991-02-08 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1994-02-07 | 1994-08-09 | 1995-02-08 | $7700.00 | Window Closed / Lapsed |