US3652908A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Fabrication of insulated gate field-effect transistors involving ion implantation
Assignee: AT&T Inc
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Filing: 1970-09-21
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Granted: 1972-03-28
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Expires: 1990-09-21
Abstract
Abstract An insulated gate field-effect transistor is made which utilizes both Schottky barrier connections and ion-implanted zones. The resultant structure incorporates source and drain zones, which are formed by ion implantation and whose spacing is fixed by the gate electrode, and source and drain electrodes which make ohmic connection to the implanted source and drain zones and rectifying connections to unimplanted material.
Inventors
- 👤 Martin P Lepselter
- 👤 Alfred U Macrae
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 12:54
CPC Classifications
H; H10; H10D; H10D62/00; H10D62/80; H10D62/83; H10D64/00; H10D64/60; H10D64/62; H10D99/00; H10P; H10P95/00; H10W; H10W20/00; H10W20/40; Y; Y10; Y10S; Y10S148/00; Y10S148/053; Y10S148/139; Y10S148/145
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
195 words
An insulated gate field-effect transistor comprising a semiconductive wafer having a surface layer which includes an intermediate portion of one conductivity type and spaced source and drain zones of the opposite conductivity type, an insulating layer overlying said surface layer and including openings overlying portions of the source and drain zones forming the source and drain openings, a gate electrode overlying part of the portion of the insulating layer extending between the source and drain openings, the width of the gate electrode being coextensive with the width of the intermediate portion of the one conductivity type extending between the source and drain zones, a separate layer of metallic material within each of the source and drain openings, each layer forming an ohmic contact with the source and drain zones, respectively, and a Schottky rectifying contact with the portion of the surface layer of one conductivity type which is contacted and which does not lie between the source and drain zones, a source electrode covering a limited portion of the layer of metallic material within the source opening, and a drain electrode covering a limited portion of the layer of metallic material within the drain opening.
Claim 2
Dependent Claim
195 words
An insulated gate field-effect transistor comprising a semiconductive wafer having a surface layer which includes an intermediate portion of one conductivity type and spaced source and drain zones of the opposite conductivity type, an insulating layer overlying said surface layer and including openings overlying portions of the source and drain zones forming the source and drain openings, a gate electrode overlying part of the portion of the insulating layer extending between the source and drain openings, the width of the gate electrode being coextensive with the width of the intermediate portion of the one conductivity type extending between the source and drain zones, a separate layer of metallic material within each of the source and drain openings, each layer forming an ohmic contact with the source and drain zones, respectively, and a Schottky rectifying contact with the portion of the surface layer of one conductivity type which is contacted and which does not lie between the source and drain zones, a source electrode covering a limited portion of the layer of metallic material within the source opening, and a drain electrode covering a limited portion of the layer of metallic material within the drain opening.
Claim 3
Dependent Claim
28 words
An insulated gate field-effect transistor in accordance with claim 1 in which each of the layers of metallic material is coextensive with the associated source and drain openings.
Claim 4
Dependent Claim
32 words
An insulated gate field-effect transistor in accordance with claim 2 in which the wafer is silicon, the insulating layer is silicon oxide and the layers of metallic material are of platinum silicide.
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) | 1975-03-28 | 1975-09-27 | 1976-03-28 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-03-28 | 1979-09-27 | 1980-03-28 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-03-28 | 1983-09-27 | 1984-03-28 | $7700.00 | Window Closed / Lapsed |