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US3629023A
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METHOD OF CHEMICALLY POLISHING CRYSTALS OF II(b){14 VI(a) SYSTEM
Assignee: 3M Co
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Filing: 1968-07-17
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Granted: 1971-12-21
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Expires: 1988-07-17
Abstract
Abstract A method and apparatus for chemically polishing crystals of the group II(B)-VI(A) system for the periodic table using a mixture consisting essentially of bromine and methanol with the bromine being present in the amount within the range of about 0.05 to about 10 percent by volume of the total solution of the mixture and forming a moving fluid film of the mixture to polish the crystal surface is shown. The apparatus includes a polishing dish and crystal support disk which supports the crystal to be polished and positions the crystal surface to be polished adjacent a plate which forms part of the polishing dish and a dispensing means which supplies a polishing solution between the plate and crystal surface for establishing a fluid film therebetween to chemically polish the crystal surface.
Inventors
- 👤 Wolfgang H Strehlow
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 20:16
CPC Classifications
H; H10; H10P; H10P50/00; B; B24; B24B; B24B37/00; B24B37/04
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
27 words
The method of claim 1 wherein said polishing dish is rotated at about 100 r.p.m. and said mixture is fed at a rate of about 10 ml./minute.
Claim 2
Dependent Claim
32 words
The method of claim 1 wherein said bromine is present in the amount within the range of about 0.05 to about 3 percent by volume of the total solution of the mixture.
Claim 3
Dependent Claim
15 words
The method of claim 1 wherein said group II(B) - VI(A) compound is cadmium selenide.
Claim 4
Dependent Claim
15 words
The method of claim 1 wherein said group II(B) - VI(A) compound is zinc sulfide.
Claim 5
Dependent Claim
14 words
The method of claim 1 wherein said group II(B)- VI(A) compound is zinc oxide.
Claim 6
Dependent Claim
31 words
The method of claim 6 for polishing zinc oxide wherein said mixture consists essentially of about 1 to about 2 percent bromine by volume of the total solution of the mixture.
Claim 7
Independent Claim
98 words
The method of polishing at least the group VI(A) face of a II(B) - VI(A) semiconductor crystal adapted for use as a solid-state laser which comprises the steps of wetting said group VI(A) face with a mixture consisting essentially of bromine in methanol, said bromine being present in an amount in the range of about 0.05 to about 5 percent by volume of the total solution of the mixture; and forming a moving fluid film of said mixture along a plane parallel to said group VI(A) face to uniformly polish said group VI(A) face at a controlled rate.
Claim 8
Dependent Claim
18 words
The method of claim 8 wherein said group II(B) - VI(A) compound is a hexagonal zinc oxide crystal.
Claim 9
Dependent Claim
18 words
The method of claim 8 wherein said group II(B) - VI(A) compound is a hexagonal zinc sulfide crystal.
Claim 10
Dependent Claim
17 words
The method of claim 8 wherein said group II(B) - VI(A) compound is hexagonal cadmium selenide crystal.
Claim 11
Dependent Claim
18 words
The method of claim 8 wherein said group II(B) - VI(A) compound is a hexagonal cadmium sulfide crystal.
Claim 12
Dependent Claim
68 words
The method of claim 8 wherein said semiconductor crystal is adapted for use as an electron beam laser wherein an electron beam penetrates said crystal through said group VI(A) face further comprising the step of controlling the time said crystal group VI(A) face is chemically polished by said fluid film such that surface disoriented atoms which form a destruction layer are substantially removed from said group VI(A) face.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1974-12-20 | 1975-06-21 | 1975-12-21 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-12-20 | 1979-06-21 | 1979-12-21 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-12-20 | 1983-06-21 | 1983-12-21 | $7700.00 | Window Closed / Lapsed |