US4374684A
Expired / Lapsed
US
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Heat treatment of cadmium mercury telluride
Assignee: Teck Metals Ltd
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Filing: 1981-01-19
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Granted: 1983-02-22
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Expires: 2001-01-19
Abstract
Abstract A method for the heat treatment of cadmium mercury telluride homogeneous single crystals is disclosed wherein the crystals are heated and maintained at a temperature in the range of from about 300 K to below the solidus temperature of the composition treated in the presence of mercury, the vapor pressure of mercury being less than the saturation vapor pressure of mercury.
Inventors
- 👤 William F. H. Micklethwaite
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 11:49
CPC Classifications
C; C01; C01B; C01B19/00; C01B19/007; C30; C30B; C30B29/00; C30B29/10; C30B29/46; C30B29/48; C30B33/00
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
172 words
A method for the heat treatment of homogeneous single crystal cadmium mercury telluride represented by the formula (Cd x Hg 1-x ) y Te 1-y wherein x has values between zero and one and y has values in the range of about 0.49 to 0.51 in an ampoule, comprising the steps of placing in said ampoule slices of said cadmium mercury telluride and a predetermined amount of mercury, evacuating and sealing the ampoule, heating the ampoule to a constant uniform temperature in the range of from about 300 K. to a temperature near but below the solidus temperature of said slices of cadmium mercury telluride, said predetermined amount of mercury being such that only vapor of said predetermined amount of mercury is present in the ampoule at said constant uniform temperature and the vapor pressure of mercury is less than the saturation vapor pressure of mercury at said constant uniform temperature, maintaining said constant uniform temperature for a period in the range of about 1 to 5000 hours, and recovering treated slices.
Claim 2
Independent Claim
172 words
A method for the heat treatment of homogeneous single crystal cadmium mercury telluride represented by the formula (Cd x Hg 1-x ) y Te 1-y wherein x has values between zero and one and y has values in the range of about 0.49 to 0.51 in an ampoule, comprising the steps of placing in said ampoule slices of said cadmium mercury telluride and a predetermined amount of mercury, evacuating and sealing the ampoule, heating the ampoule to a constant uniform temperature in the range of from about 300 K. to a temperature near but below the solidus temperature of said slices of cadmium mercury telluride, said predetermined amount of mercury being such that only vapor of said predetermined amount of mercury is present in the ampoule at said constant uniform temperature and the vapor pressure of mercury is less than the saturation vapor pressure of mercury at said constant uniform temperature, maintaining said constant uniform temperature for a period in the range of about 1 to 5000 hours, and recovering treated slices.
Claim 3
Dependent Claim
19 words
A method as claimed in claim 1, wherein x has values in the range of about 0.14 to 0.60.
Claim 4
Dependent Claim
21 words
A method as claimed in claim 1, wherein the constant temperature is in the range of about 300 to 700 K.
Claim 5
Dependent Claim
30 words
A method as claimed in claim 1 or 2 or 3, wherein said temperature is maintained for a period of time in the range of about 50 to 2000 hours.
Claim 6
Dependent Claim
33 words
A method as claimed in claim 1, or 2 or 3, wherein the vapor pressure of mercury is in the range of about 0.30 to 0.99 times the saturation vapor pressure of mercury.
Claim 7
Dependent Claim
55 words
A method as claimed in claim 2, wherein the vapor pressure of mercury is in the range of about 0.30 to 0.99 times the saturation vapor pressure of mercury, the constant temperature is about 520 K. and said temperature is maintained for a period of time in the range of about 700 to 900 hours.
Claim 8
Dependent Claim
76 words
A method as claimed in claim 1, or 2 or 3, wherein in addition to said predetermined amount of mercury, at least one of a sacrificial source material chosen from cadmium, tellurium, amalgams of cadmium and mercury, amalgams of tellurium and mercury, mercury telluride, cadmium telluride and cadmium mercury telluride is present during the heat treatment and the vapor pressure of mercury is less than the saturation vapor pressure of mercury at said constant uniform temperature.
References Cited (Backward Citations)
US3963540A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1986-02-21 | 1986-08-23 | 1987-02-22 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1990-02-21 | 1990-08-23 | 1991-02-22 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1994-02-21 | 1994-08-23 | 1995-02-22 | $7700.00 | Window Closed / Lapsed |