US3667005A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Ohmic contacts for semiconductors devices
Assignee: Texas Instruments Inc
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Filing: 1970-08-03
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Granted: 1972-05-30
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Expires: 1990-08-03
Abstract
Abstract Disclosed are methods for depositing multilayer ohmic contacts upon a substrate of semiconductor material disposed within a low pressure chamber; such including for example the particular features of upward sputtering of the various metal films, simultaneous sputtering of platinum with gold utilizing a sputtering cathode composed of platinum and gold, and adding hydrogen into an inert sputtering atmosphere to eliminate undesirable formation of oxides. This invention provides imporved adhesion of the sputtered metal films to the semiconductor surface and the silicon oxide, and provides the formation of the metal film which is substantially free of pin holes and which has substantially uniform resistivity.
Inventors
- 👤 James A Cunningham
- 👤 Coy D Orr
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 12:15
CPC Classifications
H; H10; H10D; H10D99/00; H10P; H10P95/00; H10W; H10W20/00; H10W20/40
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
161 words
A contact and lead arrangement for a semiconductor device of the type including a silicon wafer having a region adjacent one face thereof with a P-N junction between such region and other silicon of the wafer extending to said one face beneath a silicon oxide coating, the coating defining a small opening over said region, the contact and lead arrangement comprising a first triode sputtered film of molybdenum in ohmic contact with said region in said opening in the silicon oxide coating, the triode sputtered film of molybdenum extending from said opening out over said silicon oxide coating in direct contact therewith and over the edge of said junction to a position spaced from said region on said one face, and a second triode sputtered film of platinum and gold overlying said film of molybdenum wherein said second triode sputtered film is comprised of gold in the range of 90-98 percent and platinum in the range of 10-2 percent by weight.
Claim 2
Dependent Claim
161 words
A contact and lead arrangement for a semiconductor device of the type including a silicon wafer having a region adjacent one face thereof with a P-N junction between such region and other silicon of the wafer extending to said one face beneath a silicon oxide coating, the coating defining a small opening over said region, the contact and lead arrangement comprising a first triode sputtered film of molybdenum in ohmic contact with said region in said opening in the silicon oxide coating, the triode sputtered film of molybdenum extending from said opening out over said silicon oxide coating in direct contact therewith and over the edge of said junction to a position spaced from said region on said one face, and a second triode sputtered film of platinum and gold overlying said film of molybdenum wherein said second triode sputtered film is comprised of gold in the range of 90-98 percent and platinum in the range of 10-2 percent by weight.
Claim 3
Dependent Claim
22 words
The arrangement as described in claim 1 including a sintered platinum silicide contact intermediate said region and said first triode sputtered film.
Claim 4
Dependent Claim
23 words
The arrangement as described in claim 1 including a layer of evaporated gold overlying said second triode sputtered film of platinum and gold.
Claim 5
Dependent Claim
153 words
A contact and lead arrangement for a semiconductor device of the type including a silicon wafer having a region adjacent one face thereof with a P-N junction between such region and other silicon of the wafer extending to said one face beneath a silicon oxide coating, the coating defining a small opening over said region, the contact and lead arrangement comprising a first film of molybdenum in ohmic contact with said region in said opening in the silicon oxide coating, the film of molybdenum extending from said opening out over said silicon oxide coating in direct contact therewith and over the edge of said junction to a position spaced from said region on said one face, and a second film of platinum and gold overlying said film of molybdenum wherein said second film is comprised of gold in the range of 90-98 percent and platinum in the range of 10-2 percent by weight.
Claim 6
Dependent Claim
153 words
A contact and lead arrangement for a semiconductor device of the type including a silicon wafer having a region adjacent one face thereof with a P-N junction between such region and other silicon of the wafer extending to said one face beneath a silicon oxide coating, the coating defining a small opening over said region, the contact and lead arrangement comprising a first film of molybdenum in ohmic contact with said region in said opening in the silicon oxide coating, the film of molybdenum extending from said opening out over said silicon oxide coating in direct contact therewith and over the edge of said junction to a position spaced from said region on said one face, and a second film of platinum and gold overlying said film of molybdenum wherein said second film is comprised of gold in the range of 90-98 percent and platinum in the range of 10-2 percent by weight.
Claim 7
Dependent Claim
20 words
The arrangement as described in claim 4 including a sintered platinum silicide contact intermediate said region and said first film.
Claim 8
Dependent Claim
21 words
The arrangement as described in claim 4 including a layer of evaporated gold overlying said second film of platinum and gold.
Claim 9
Dependent Claim
169 words
A contact and lead arrangement for a semiconductor device comprising in combination: a. a substrate of semiconductor material of one conductivity type; b. a plurality of opposite conductivity type regions at one major face of said substrate; c. a layer of insulating material overlying and adherent to said one major face with a plurality of apertures formed therein and exposing selected portions of said regions; d. a layer of platinum silicide in ohmic contact with each of said exposed portions of said regions; e. a first triode-sputtered layer of molybdenum overlying and adhered to said portions of insulating layer and in ohmic contact with said platinum silicide layer; said first triode-sputtered layer selectively connecting said regions; f. a second triode-sputtered layer of platinum and gold alloy overlying and in ohmic contact with said first triode-sputtered layer, said second triode-sputtered layer being comprised of 5 percent platinum and 95 percent gold by weight; and g. an evaporated layer oF gold overlying and in ohmic contact with said second triode-sputtered layer.
Claim 10
Dependent Claim
169 words
A contact and lead arrangement for a semiconductor device comprising in combination: a. a substrate of semiconductor material of one conductivity type; b. a plurality of opposite conductivity type regions at one major face of said substrate; c. a layer of insulating material overlying and adherent to said one major face with a plurality of apertures formed therein and exposing selected portions of said regions; d. a layer of platinum silicide in ohmic contact with each of said exposed portions of said regions; e. a first triode-sputtered layer of molybdenum overlying and adhered to said portions of insulating layer and in ohmic contact with said platinum silicide layer; said first triode-sputtered layer selectively connecting said regions; f. a second triode-sputtered layer of platinum and gold alloy overlying and in ohmic contact with said first triode-sputtered layer, said second triode-sputtered layer being comprised of 5 percent platinum and 95 percent gold by weight; and g. an evaporated layer oF gold overlying and in ohmic contact with said second triode-sputtered layer.
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) | 1975-05-30 | 1975-11-29 | 1976-05-30 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-05-30 | 1979-11-29 | 1980-05-30 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-05-30 | 1983-11-29 | 1984-05-30 | $7700.00 | Window Closed / Lapsed |