US5028296A
Expired / Lapsed
US
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Annealing method
Assignee: DRS Infrared Technologies LP
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Filing: 1989-09-15
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Granted: 1991-07-02
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Expires: 2009-09-15
Abstract
Abstract A three step annealing treatment for Hg 1-x Cd x Te includes a high temperature anneal to reduce excess tellurium, followed by an intermediate temperature anneal to reduce the supersaturation of metal vacancies, and lastly a low temperature anneal to reduce metal vacancies; see FIG. 4. The intermediate anneal reduces the metal vacancy concentration sufficiently that microvoids do not form from condensation of metal vacancies in desired portions of the Hg 1-x Cd x Te during the low temperature anneal. Alternate preferred embodiments include more than three steps and incremental cooling.
Inventors
- 👤 John H. Tregilgas
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-07 06:32
CPC Classifications
H; H10; H10P; H10P95/00; H10P95/90; C; C30; C30B; C30B29/00; C30B29/10; C30B29/46; C30B29/48; C30B33/00; Y; Y10; Y10S; Y10S438/00; Y10S438/971
Claims Analysis
Total Claims: 20
Claim 1
Independent Claim
90 words
A method of Hg 1-x Cd x Te treatment, comprising the steps of: (a) providing a body of Hg 1-x Cd x Te; (b) placing said body of Hg 1-x Cd x Te in an atmosphere sufficiently rich in mercury to allow said mercury to diffuse into said body; and (c) annealing said body of Hg 1-x Cd x Te in said atmosphere sufficiently rich in mercury to allow said mercury to diffuse into said body at at least three successively lower temperatures to deter microvoid formation in said body.
Claim 2
Independent Claim
90 words
A method of Hg 1-x Cd x Te treatment, comprising the steps of: (a) providing a body of Hg 1-x Cd x Te; (b) placing said body of Hg 1-x Cd x Te in an atmosphere sufficiently rich in mercury to allow said mercury to diffuse into said body; and (c) annealing said body of Hg 1-x Cd x Te in said atmosphere sufficiently rich in mercury to allow said mercury to diffuse into said body at at least three successively lower temperatures to deter microvoid formation in said body.
Claim 3
Independent Claim
143 words
A method of Hg 1-x Cd x Te treatment, comprising the steps of: (a) providing a body of Hg 1-x Cd x Te; (b) annealing said body of Hg 1-x Cd x Te at a first temperature; (c) placing said body of Hg 1-x Cd x Te from step (b) in an atmosphere sufficiently rich in mercury to allow said mercury to diffuse into said body; (d) next annealing said body at a second temperature in an atmosphere sufficiently rich in mercury to allow said mercury to diffuse into said body, said second temperature being at least 100° C. lower than said first temperature; and (e) then annealing said body at a third temperature in an atmosphere sufficiently rich in mercury to allow said mercury to diffuse into said body, said third temperature being at least 100° C. lower than said second temperature.
Claim 4
Independent Claim
143 words
A method of Hg 1-x Cd x Te treatment, comprising the steps of: (a) providing a body of Hg 1-x Cd x Te; (b) annealing said body of Hg 1-x Cd x Te at a first temperature; (c) placing said body of Hg 1-x Cd x Te from step (b) in an atmosphere sufficiently rich in mercury to allow said mercury to diffuse into said body; (d) next annealing said body at a second temperature in an atmosphere sufficiently rich in mercury to allow said mercury to diffuse into said body, said second temperature being at least 100° C. lower than said first temperature; and (e) then annealing said body at a third temperature in an atmosphere sufficiently rich in mercury to allow said mercury to diffuse into said body, said third temperature being at least 100° C. lower than said second temperature.
Claim 5
Dependent Claim
19 words
The method of claim 2, wherein: (a) said body is divided into smaller pieces between steps (b) and (d).
Claim 6
Dependent Claim
19 words
The method of claim 2, wherein: (a) said body is divided into smaller pieces between steps (d) and (e).
Claim 7
Independent Claim
140 words
A method of mercury-component semiconductor material treatment, comprising the steps of: (a) annealing a body of mercury-component semiconductor material at a first temperature in a mercury ambient sufficiently rich in mercury to allow said mercury to diffuse into said body; (b) next annealing said body from step (a) at a second temperature lower than said first temperature in a mercury ambient sufficiently rich in mercury to allow said mercury to diffuse into said body to provide a supersaturation of metal vacancies in said mercury-component semiconductor material of less than 500; and (c) then annealing said body (from step b) at a third temperature lower than said second temperature in a mercury ambient sufficiently rich in mercury to allow said mercury to diffuse into said body to provide a supersaturation of metal vacancies in said mercury-component semiconductor of less than 1000.
Claim 8
Independent Claim
140 words
A method of mercury-component semiconductor material treatment, comprising the steps of: (a) annealing a body of mercury-component semiconductor material at a first temperature in a mercury ambient sufficiently rich in mercury to allow said mercury to diffuse into said body; (b) next annealing said body from step (a) at a second temperature lower than said first temperature in a mercury ambient sufficiently rich in mercury to allow said mercury to diffuse into said body to provide a supersaturation of metal vacancies in said mercury-component semiconductor material of less than 500; and (c) then annealing said body (from step b) at a third temperature lower than said second temperature in a mercury ambient sufficiently rich in mercury to allow said mercury to diffuse into said body to provide a supersaturation of metal vacancies in said mercury-component semiconductor of less than 1000.
Claim 9
Dependent Claim
16 words
The method of claim 5, wherein: (a) the supersaturation in step (b) is less than 50.
Claim 10
Dependent Claim
16 words
The method of claim 5, wherein: (a) the supersaturation in step (c) is less than 300.
Claim 11
Dependent Claim
41 words
The method of claim 5, further comprising the step of: (a) lastly annealing said body at a fourth temperature in a mercury ambient, (b) wherein the supersaturation steps at each of the second, third, and fourth anneals is less than 200.
Claim 12
Dependent Claim
29 words
The method of claim 5, wherein: (a) said semiconductor is Hg 1-x Cd x Te; and (b) said semiconductor is maintained within the mercury and tellurium saturated phase limits.
Claim 13
Dependent Claim
41 words
The method of claim 9, further comprising the step of: (a) lastly annealing said body at a fourth temperature in a mercury ambient, (b) wherein the supersaturation steps at each of the second, third, and fourth anneals is less than 200.
Claim 14
Dependent Claim
15 words
The method of claim 1 wherein said mercury cadmium telluride in step (a) is recrystallized.
Claim 15
Dependent Claim
15 words
The method of claim 2 wherein said mercury cadmium telluride in step (a) is recrystallized.
Claim 16
Dependent Claim
15 words
The method of claim 5 wherein said mercury-component semiconductor material in step (a) is recrystallized.
Claim 17
Dependent Claim
28 words
The method of claim 2 wherein said first temperature is about 600° C. said second temperature is about 400° C. and said third temperature is about 270° C.
Claim 18
Dependent Claim
28 words
The method of claim 12 wherein said first temperature is about 600° C. said second temperature is about 400° C. and said third temperature is about 270° C.
Claim 19
Dependent Claim
28 words
The method of claim 5 wherein said first temperature is about 600° C. said second temperature is about 400° C. and said third temperature is about 270° C.
Claim 20
Dependent Claim
28 words
The method of claim 13 wherein said first temperature is about 600° C. said second temperature is about 400° C. and said third temperature is about 270° C.
References Cited (Backward Citations)
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