US4085500A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Ohmic contacts to p-type mercury cadmium telluride
Assignee: Honeywell Inc
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Filing: 1976-09-29
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Granted: 1978-04-25
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Expires: 1996-09-29
Abstract
Abstract Ohmic contacts to p-type mercury cadmium telluride are prepared by depositing a Column IB metal on a surface of the p-type mercury cadmium telluride, depositing a buffer material on the Column IB metal, and contacting the buffer material with a bonding material which is capable of alloying with the Column IB metal. The buffer material prevents alloying between the Column IB metal and the bonding material.
Inventors
- 👤 Robert J. Hager
- 👤 Eric S. Johnson
- 👤 M. Walter Scott
- 👤 Ernest L. Stelzer
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 15:51
CPC Classifications
H; H10; H10F; H10F30/00; H10F30/20; H10F30/21; H10F30/22; H10F30/221; H10F30/2212; H10D; H10D62/00; H10D62/80; H10D62/86; H10D62/862; H10D64/00; H10D64/60; H10D64/62; H10P; H10P14/00; H10P14/40; H10P14/46; H10P14/47; H10W; H10W72/00; H10W72/90; H10W72/50; H10W72/531; H10W72/536; H10W72/59
Claims Analysis
Total Claims: 26
Claim 1
Independent Claim
53 words
A method of forming a contact to p-type mercury cadmium telluride, the method comprising: depositing a Column IB metal on at least a portion of a surface of p-type mercury cadmium telluride; depositing a buffer material on the Column IB metal; and contacting the buffer material with a low melting temperature bonding material.
Claim 2
Independent Claim
53 words
A method of forming a contact to p-type mercury cadmium telluride, the method comprising: depositing a Column IB metal on at least a portion of a surface of p-type mercury cadmium telluride; depositing a buffer material on the Column IB metal; and contacting the buffer material with a low melting temperature bonding material.
Claim 3
Dependent Claim
19 words
The method of claim 1 and further comprising: diffusing the Column IB metal into the p-type mercury cadmium telluride.
Claim 4
Dependent Claim
16 words
The method of claim 2 and further comprising: further depositing the Column IB metal after diffusing.
Claim 5
Dependent Claim
12 words
The method of claim 3 wherein the Column IB metal is gold.
Claim 6
Dependent Claim
18 words
The method of claim 4 wherein the initial depositing of the Column IB metal is by vapor deposition.
Claim 7
Dependent Claim
17 words
The method of claim 5 wherein the further depositing of the Column IB metal is by electroplating.
Claim 8
Dependent Claim
24 words
The method of claim 4 wherein diffusing is by heating the Column IB metal and the p-type mercury cadmium telluride in a controlled atmosphere.
Claim 9
Dependent Claim
20 words
The method of claim 7 wherein the heating is at a temperature of about 500° K to about 600° K.
Claim 10
Dependent Claim
11 words
The method of claim 8 wherein the controlled atmosphere is hydrogen.
Claim 11
Dependent Claim
13 words
The method of claim 1 wherein the buffer material is a transition metal.
Claim 12
Dependent Claim
11 words
The method of claim 10 wherein the buffer material is nickel.
Claim 13
Dependent Claim
14 words
The method of claim 11 wherein depositing the buffer material is by electroless plating.
Claim 14
Dependent Claim
23 words
The method of claim 1 wherein the low melting temperature bonding material is of the group consisting of indium, aluminum, and alloys thereof.
Claim 15
Dependent Claim
14 words
The method of claim 13 wherein the material contacting the buffer material is indium.
Claim 16
Dependent Claim
12 words
The method of claim 14 wherein the Column IB metal is gold.
Claim 17
Dependent Claim
11 words
The method of claim 15 wherein the buffer material is nickel.
Claim 18
Dependent Claim
35 words
The method of claim 1 and further comprising masking at least a portion of a surface of the p-type mercury cadmium telluride during depositing of the Column IB metal and depositing of the buffer material.
Claim 19
Dependent Claim
30 words
The method of claim 17 and further comprising removing a mask from at least a portion of the surface of the p-type mercury cadmium telluride after depositing the buffer material.
Claim 20
Dependent Claim
35 words
The method of claim 18 and further comprising masking the Column IB metal and the buffer material after removing the mask from at least a portion of the surface of the p-type mercury cadmium telluride.
Claim 21
Dependent Claim
27 words
The method of claim 19 and further comprising cleaning the surface of the p-type mercury cadmium telluride after masking the Column IB metal and the buffer material.
Claim 22
Dependent Claim
10 words
The method of claim 20 wherein cleaning is by etching.
Claim 23
Dependent Claim
12 words
The method of claim 21 wherein etching is with a bromine-alcohol solution.
Claim 24
Dependent Claim
17 words
The method of claim 22 wherein etching for a period of about 30 to about 60 seconds.
Claim 25
Dependent Claim
44 words
The method of claim 1 wherein the low melting temperature bonding material is of the group of materials which are donors in mercury cadmium telluride and which are capable of alloying with the Column IB metal at a temperature less than about 700° K.
Claim 26
Dependent Claim
43 words
The method of claim 24 wherein the buffer material is of the group of materials which do not substantially alloy with the Column IB metal or substantially react with the low melting temperature bonding material at a temperature less than about 700° K.
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) | 1981-04-24 | 1981-10-24 | 1982-04-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1985-04-24 | 1985-10-24 | 1986-04-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1989-04-24 | 1989-10-24 | 1990-04-25 | $7700.00 | Window Closed / Lapsed |