US4805178A
Expired / Lapsed
US
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Preservation of surface features on semiconductor surfaces
Assignee: Nokia Bell Labs
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Filing: 1986-03-28
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Granted: 1989-02-14
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Expires: 2006-03-28
Abstract
Abstract The integrity of surface structural features (e.g., distributed feedback gratings) in Group III-V compound semiconductors are preserved during heating (e.g., subsequent LPE regrowth) by a thin coating containing a transition metal (e.g., Os, Ru and Rh). DFB-DCPBH InP/InGaAsP single frequency lasers made in this way are also described.
Inventors
- 👤 Daniel P. Wilt
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 21:40
CPC Classifications
H; H01; H01S; H01S5/00; H01S5/02; H01S5/028; H01S5/10; H01S5/12; H01S5/20; H01S5/22; H01S5/227; H10; H10H; H10H20/00; H10H20/01; H10H20/011; H10H20/013; H10P; H10P14/00; H10P14/20; H10P14/26; H10P14/263; H10P14/32; H10P14/3202; H10P14/3214; H10P14/3218; H10P14/3221; H10P14/34; H10P14/3402; H10P14/3414; H10P14/3418; H10P14/3438; H10P14/3441; H10P14/3446; H10P14/36; H10P14/38; H10P14/3802; H10P14/3806; H10P95/00; H10P95/90; H10P95/904; H01S5/1231; H01S5/2275; H01S5/2277; H01S5/30; H01S5/32; H01S5/323; H01S5/3235; H01S5/32391
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
97 words
A semiconductor laser comprising a Group III-V compound semiconductor body having a major surface, p1 an optical grating on said major surface, a protective coating on said grating, said coating including a transition metal, a Group III-V compound semiconductor heterostructure formed on said coating, said heterostructure having the shape of a mesa and including a Group III-V compound semiconductor active layer, a current-blocking Group III-V compound semiconductor structure laterally adjacent said mesa and effective to direct the primary flow of current through said mesa during operation of said laser, and means forming electrical contact to said laser.
Claim 2
Dependent Claim
97 words
A semiconductor laser comprising a Group III-V compound semiconductor body having a major surface, p1 an optical grating on said major surface, a protective coating on said grating, said coating including a transition metal, a Group III-V compound semiconductor heterostructure formed on said coating, said heterostructure having the shape of a mesa and including a Group III-V compound semiconductor active layer, a current-blocking Group III-V compound semiconductor structure laterally adjacent said mesa and effective to direct the primary flow of current through said mesa during operation of said laser, and means forming electrical contact to said laser.
Claim 3
Dependent Claim
10 words
The laser of claim 1 wherein said coating contains Ru.
Claim 4
Dependent Claim
10 words
The laser of claim 1 wherein said coating contains Rh.
Claim 5
Dependent Claim
19 words
The laser of claims 1, 2 or 3 wherein said body comprises InP and said active layer comprises InGaAsP.
Claim 6
Dependent Claim
21 words
The laser of claim 4 wherein the composition of said active layer emits light at a wavelength of about 1.5 μm.
Claim 7
Dependent Claim
35 words
The laser of claims 1, 2 or 3 wherein said heterostructure further includes a Group III-V compound semiconductor waveguide layer having a bandgap wider than that of said active layer and being optically coupled thereto.
Claim 8
Dependent Claim
21 words
The laser of claim 6 wherein said body comprises InP, said active layer comprises InGaAsP and said waveguide layer comprises InGaAsP.
Claim 9
Dependent Claim
21 words
The laser of claim 7 wherein the composition of said active layer emits light at a wavelength of about 1.5 μm.
References Cited (Backward Citations)
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| 7.5 Years (Year 8) | 1996-02-14 | 1996-08-15 | 1997-02-14 | $3760.00 | Window Closed / Lapsed |
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