US4418096A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process for preparing layers of Hg1-x Cdx Te
Assignee: Societe Anonyme de Telecommunications SAT
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Filing: 1981-11-19
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Granted: 1983-11-29
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Expires: 2001-11-19
Abstract
Abstract A process for preparing layers with a superficial composition of Hg1-xCdxTe comprising the steps of producing a wafer by forming a layer of superficial composition Hg1-yCdyTe on a substrate of CdTe, y being less than the desired value x, and subjecting this wafer to a thermal interdiffusion treatment at a temperature of between about 350 DEG and about 750 DEG C., under such conditions that the layer of Hg1-yCdyTe cannot decompose.
Inventors
- 👤 Andre Gauthier
- 👤 Jean C. F. Morand
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 13:36
CPC Classifications
C; C22; C22C; C22C1/00; H; H10; H10F; H10F71/00; H10F71/125; H10F71/1253
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
127 words
A process for preparing layers of an alloy Hg 1-x Cd x Te useful in the manufacture of infrared detectors, comprising the steps of introducing into a tube a wafer having a substrate of Cd Te and a superficial layer of Hg 1-y Cd y Te, the value of y being less than the desired value of x, applying a mask above the wafer adding a quantity of mercury above the mask, introducing a piston into the tube for holding the whole in position, creating a vacuum inside the tube, sealing the tube, placing the tube in a furnace whose temperature is between 350° C. and 750° C. to subject the wafer to a thermal interdiffusion treatment without decomposing the layer of Hg 1-y Cd y Te.
Claim 2
Dependent Claim
127 words
A process for preparing layers of an alloy Hg 1-x Cd x Te useful in the manufacture of infrared detectors, comprising the steps of introducing into a tube a wafer having a substrate of Cd Te and a superficial layer of Hg 1-y Cd y Te, the value of y being less than the desired value of x, applying a mask above the wafer adding a quantity of mercury above the mask, introducing a piston into the tube for holding the whole in position, creating a vacuum inside the tube, sealing the tube, placing the tube in a furnace whose temperature is between 350° C. and 750° C. to subject the wafer to a thermal interdiffusion treatment without decomposing the layer of Hg 1-y Cd y Te.
Claim 3
Dependent Claim
27 words
The process as claimed in claim 1, wherein said wafer is subjected to said thermal interdiffusion treatment under a mercury pressure of between 4 and 50 atmospheres.
Claim 4
Dependent Claim
17 words
The process as claimed in claim 2, wherein the mercury pressure is between 6 and 12 atmospheres.
Claim 5
Dependent Claim
32 words
The process as claimed in claim 1, wherein prior to the thermal treatment, a thin layer of CdTe is deposited on the wafer over the layer of Hg 1-y Cd y Te.
Claim 6
Dependent Claim
18 words
The process as claimed in claim 4, wherein the thickness of the CdTe layer is about 5 μm.
Claim 7
Dependent Claim
20 words
The process as claimed in claim 1, wherein the furnace temperature ranges from about 550° C. to about 600° C.
References Cited (Backward Citations)
FR1447257A
Cited
US3725135A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1986-11-28 | 1987-05-30 | 1987-11-29 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1990-11-28 | 1991-05-30 | 1991-11-29 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1994-11-28 | 1995-05-30 | 1995-11-29 | $7700.00 | Window Closed / Lapsed |