Patent US4980313A successfully refreshed from Google Patents.
US4980313A
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Method of producing a semiconductor laser
Assignee: Mitsubishi Electric Corp
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Filing: 1990-01-05
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Granted: 1990-12-25
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Expires: 2010-01-05
Abstract
Abstract A method of producing a semiconductor laser including deposition a first film as a source of n type impurities on a portion of a semiconductor structure produced by growing at least a p type lower cladding layer, a quantum well active layer, and an n type upper cladding layer successively on a substrate, depositing a second film as a source of p type impurities at least on the surface of the semiconductor structure on both sides of and on the first film and annealing to diffuse p and n type impurities at the same time, thereby disordering portions of the quantum well except for the portion becoming an active region with p type impurities reaching at least the p type lower cladding layer, n type impurities reverting the portions of the n type cladding layer to which p type impurities have diffused to n type, and the n type impurities reaching the n type cladding layer but not reaching the active layer.
Inventors
- 👤 Shogo Takahashi
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 23:43
CPC Classifications
H; H10; H10H; H10H20/00; H10H20/80; H10H20/81; H10H20/822; H10H20/824; H10H20/8242; B; B82; B82Y; B82Y20/00; H01; H01S; H01S5/00; H01S5/20; H10H20/01; H10H20/011; H10H20/013; H10H20/811; H10H20/812; H01S5/2054; H01S5/2059; Y; Y10; Y10S; Y10S148/00; Y10S148/015; Y10S148/095; Y10S148/151; Y10S148/16
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
163 words
A method of producing a semiconductor laser comprising: growing at least a p type lower cladding layer, a quantum well active layer, and an type upper cladding layer successively on a substrate; depositing a first film as a source for diffusion of n type impurities on a portion of the n type upper cladding layer; depositing a second film as a source for diffusion of p type impurities at least on the upper cladding layer on opposite sides of the first film; and annealing to diffuse p and n type impurities at the same time, thereby to disorder portions of the quantum well except for a portion becoming the active region of the laser with p type impurities reaching the p type lower cladding layer, n type impurities reverting portions of the n type cladding layer to which p type impurities have diffused to n type, and n type impurities entering the n type upper cladding layer but not reaching the active layer.
Claim 2
Independent Claim
163 words
A method of producing a semiconductor laser comprising: growing at least a p type lower cladding layer, a quantum well active layer, and an type upper cladding layer successively on a substrate; depositing a first film as a source for diffusion of n type impurities on a portion of the n type upper cladding layer; depositing a second film as a source for diffusion of p type impurities at least on the upper cladding layer on opposite sides of the first film; and annealing to diffuse p and n type impurities at the same time, thereby to disorder portions of the quantum well except for a portion becoming the active region of the laser with p type impurities reaching the p type lower cladding layer, n type impurities reverting portions of the n type cladding layer to which p type impurities have diffused to n type, and n type impurities entering the n type upper cladding layer but not reaching the active layer.
Claim 3
Dependent Claim
12 words
The method of claim 1 including depositing silicon as the first film.
Claim 4
Dependent Claim
18 words
The method of claim 2 including depositing a mixture of ZnO and SiO 2 as the second film.
Claim 5
Dependent Claim
13 words
The method of claim 1 wherein said active layer comprises multi-quantum well structure.
Claim 6
Dependent Claim
14 words
The method of claim 1 wherein said active layer comprises single quantum well structure.
Claim 7
Dependent Claim
17 words
The method of claim 1 including depositing an SiO 2 film on the second film before annealing.
Claim 8
Dependent Claim
34 words
The method of claim 1 wherein the p type lower cladding layer comprises AlGaAs, the quantum well active layer comprises AlGaAs, the n type upper cladding layer comprises AlGaAs and the substrate comprises GaAs.
Claim 9
Dependent Claim
26 words
The method of claim 7 including growing an n type GaAs contact layer on said n type AlGaAs upper cladding layer before depositing said first film.
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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) | 1993-12-24 | 1994-06-25 | 1994-12-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1997-12-24 | 1998-06-25 | 1998-12-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2001-12-24 | 2002-06-25 | 2002-12-25 | $7700.00 | Window Closed / Lapsed |