Patent EP0090135A1 successfully refreshed from Google Patents.
EP0090135A1
Expired / Lapsed
EP
⏱️ 0.0 years remaining
Semiconductor injection lasers
Assignee: International Business Machines Corp
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Filing: 1983-01-21
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Granted: —
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Expires: 2003-01-21
Abstract
Abstract Degradation of the cleaved light output surface (3, 4) of a semiconductor crystal injection laser (1) is reduced through control of surface recombination by providing an annealed optically transparent coating (7) at least one ingredient of which has a higher bandgap than said crystal over the cleaved light output surface. Crystals of GaAs, GaAlAs and GaInAsP are provided with annealed coatings of ZnS, CdS, CdTe and CdSe.
Inventors
- 👤 Thomas Nelson Jackson
- 👤 Jerry Mac Pherson Woodall
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-10-30 22:33
CPC Classifications
H; H01; H01S; H01S5/00; H01S5/02; H01S5/028; H01S5/0281; H10; H10H; H10H20/00; H10H20/80
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
59 words
Semiconductor crystal injection laser of the type having an active lasing region essentially perpenducular to a cleaved light output surface, characterized by means for reducing heating produced by carrier surface recombination at the cleaved surface comprising an annealed coating of an optically transparent compound at least one element thereof having a higher bandgap than that of said laser crystal.
Claim 2
Dependent Claim
59 words
Semiconductor crystal injection laser of the type having an active lasing region essentially perpenducular to a cleaved light output surface, characterized by means for reducing heating produced by carrier surface recombination at the cleaved surface comprising an annealed coating of an optically transparent compound at least one element thereof having a higher bandgap than that of said laser crystal.
Claim 3
Dependent Claim
15 words
The laser of claim 1 wherein said semiconductor is formed of GaAs, GaAlAs or GaInAsP.
Claim 4
Dependent Claim
19 words
The laser of claims 1 and 2 wherein said annealed coating is formed of ZnS, CdS, CdTe or CdSe.
Claim 5
Dependent Claim
31 words
The laser of claim 1 characterized by at least one cleaved light output surface and ohmic contacts on the sides thereof, the annealed coating being of a surface recombination control material.
Claim 6
Dependent Claim
196 words
The process of providing a semiconductor crystal laser according to the preceeding claims comprising in combination the steps of: providing a compound semiconductor cleaved laser body having first and second essentially parallel surfaces and having a laser active region essentially perpendicular to said first and second surfaces and having the length dimension of said laser active region defined by cleaved light output faces of said body, applying a mask on said first surface that terminates at a specific region proximate but separated from each said cleaved light output face, depositing a recombination control material in an optically transparent compound at least one ingredient of which has a bandgap larger than that of said laser crystal in the form of a coating over each said light output face and over said mask but not over said specific region from said mask to said cleaved light output faces, applying a lift-off type coating over said recombination control material coating, removing said mask, annealing said coating of recombination control material, metallizing said first and second surfaces, said metallizing extending over said recombination control coating, and lifting off said metallizing from said recombination control coating by dissolving said lift-off coating.
References Cited (Backward Citations)
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