US5508225A
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US
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Method for manufacturing semiconductor visible laser diode
Assignee: Mitsubishi Electric Corp
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Filing: 1994-03-28
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Granted: 1996-04-16
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Expires: 2014-03-28
Abstract
Abstract In a method for manufacturing a semiconductor laser diode, producing visible light after growing a p type GaAs contact layer on a p type AlGaInP cladding layer, an n type layer comprising that can be selectively etched with an etchant that does not etch GaAs is grown on the p type GaAs contact layer. After cooling, the n type layer is selectively etched and removed. In this method, a diffusion potential produced at the p-n junction between the p type GaAs contact layer and the n type layer prevents ionized hydrogen from entering the p type AlGaInP cladding layer during cooling, whereby the activation ratio of Zn atoms in the p type AlGaInP cladding layer is increased. Therefore, even if the Zn/III ratio during the growth of the p type AlGaInP cladding layer is low, a semiconductor laser diode with reduced threshold current and improved temperature characteristics is attained. In addition, since the n type layer grown on the p type GaAs contact layer comprises a semiconductor material that can be selectively etched with an etchant that does not etch GaAs, the etching process of the n type layer is carried out with high controllability without adversely affecting the surface of the p type GaAs contact layer, resulting in a highly reliable semiconductor laser diode.
Inventors
- 👤 Kaoru Kadoiwa
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 06:47
CPC Classifications
H; H01; H01S; H01S5/00; H01S5/30; H01S5/305; H01S5/20; H01S5/22; H01S5/223; H01S5/2231; H01S5/3054; H01S5/32; H01S5/3202; H01S5/3211; H01S5/323; H01S5/32308; H01S5/32325; Y; Y10; Y10S; Y10S148/00; Y10S148/095
Claims Analysis
Total Claims: 23
Claim 1
Independent Claim
112 words
A method for manufacturing a semiconductor laser diode producing visible light and including a p type AlGaInP cladding layer on an active layer, said method including: successively growing an active layer, a p type AlGaInP cladding layer, and a p type GaAs cap layer on a semiconductor substrate; regrowing a p type GaAs contact layer on said p type GaAs cap layer; growing a first n type layer on said p type GaAs contact layer, said first n type layer comprising a semiconductor material that can be selectively etched with an etchant that does not etch GaAs and, thereafter, cooling the wafer; and selectively etching and removing said first n type layer.
Claim 2
Independent Claim
112 words
A method for manufacturing a semiconductor laser diode producing visible light and including a p type AlGaInP cladding layer on an active layer, said method including: successively growing an active layer, a p type AlGaInP cladding layer, and a p type GaAs cap layer on a semiconductor substrate; regrowing a p type GaAs contact layer on said p type GaAs cap layer; growing a first n type layer on said p type GaAs contact layer, said first n type layer comprising a semiconductor material that can be selectively etched with an etchant that does not etch GaAs and, thereafter, cooling the wafer; and selectively etching and removing said first n type layer.
Claim 3
Dependent Claim
21 words
The method of claim 1 including adding Zn as a p type impurity dopant while growing said p type AlGaInP layer.
Claim 4
Dependent Claim
26 words
The method of claim 1 including cooling said semiconductor substrate in one of a hydrogen atmosphere, a nitrogen atmosphere, and a mixture of hydrogen and nitrogen.
Claim 5
Dependent Claim
18 words
The method of claim 1 including growing an n type AlGaInP layer as said first n type layer.
Claim 6
Dependent Claim
17 words
The method of claim 4 including selectively etching said first n type AlGaInP layer with hydrochloric acid.
Claim 7
Dependent Claim
35 words
The method of claim 4 including: successively growing said first n type AlGaInP layer and a first GaAs layer; and selectively etching and removing said first GaAs layer and said first n type AlGaInP layer.
Claim 8
Dependent Claim
20 words
The method of claim 6 including selectively etching said first GaAs layer with one of tartaric acid and sulfuric acid.
Claim 9
Independent Claim
228 words
A method for manufacturing a semiconductor laser diode producing visible light and including a p type AlGaInP cladding layer on an active layer, said method comprising: successively growing an n type AlGaInP cladding layer, a GaInP active layer, a p type AlGaInP cladding layer, and a p type GaAs cap layer on an n type GaAs substrate; forming a stripe-shaped insulating film pattern on a part of said p type GaAs cap layer; removing portions of said p type GaAs cap layer and said p type AlGaInP cladding layer by etching using said insulating film pattern as a mask to form a stripe-shaped ridge; using said insulating film pattern as a mask, selectively growing an n type GaAs current blocking layer on said p type AlGaInP cladding layer contacting opposite side walls of said ridge; removing said insulating film pattern; growing a p type GaAs contact layer on said p type GaAs cap layer and on said n type GaAs current blocking layer and, successively, growing an n type AlGaInP layer and a GaAs layer on said p type GaAs contact layer and, thereafter, cooling the wafer; selectively etching and removing said GaAs layer and said n type AlGaInP layer; and forming a p side electrode on said p type GaAs contact layer and an n side electrode on the rear surface of said n type GaAs substrate.
Claim 10
Independent Claim
228 words
A method for manufacturing a semiconductor laser diode producing visible light and including a p type AlGaInP cladding layer on an active layer, said method comprising: successively growing an n type AlGaInP cladding layer, a GaInP active layer, a p type AlGaInP cladding layer, and a p type GaAs cap layer on an n type GaAs substrate; forming a stripe-shaped insulating film pattern on a part of said p type GaAs cap layer; removing portions of said p type GaAs cap layer and said p type AlGaInP cladding layer by etching using said insulating film pattern as a mask to form a stripe-shaped ridge; using said insulating film pattern as a mask, selectively growing an n type GaAs current blocking layer on said p type AlGaInP cladding layer contacting opposite side walls of said ridge; removing said insulating film pattern; growing a p type GaAs contact layer on said p type GaAs cap layer and on said n type GaAs current blocking layer and, successively, growing an n type AlGaInP layer and a GaAs layer on said p type GaAs contact layer and, thereafter, cooling the wafer; selectively etching and removing said GaAs layer and said n type AlGaInP layer; and forming a p side electrode on said p type GaAs contact layer and an n side electrode on the rear surface of said n type GaAs substrate.
Claim 11
Dependent Claim
21 words
The method of claim 8 including adding Zn as a p type impurity dopant while growing said p type AlGaInP layer.
Claim 12
Dependent Claim
26 words
The method of claim 8 including cooling said semiconductor substrate in one of a hydrogen atmosphere, a nitrogen atmosphere, and a mixture of hydrogen and nitrogen.
Claim 13
Dependent Claim
30 words
The method of claim 8 including selectively etching said n type AlGaInP layer with hydrochloric acid and selectively etching said GaAs layer with one of tartaric acid and sulfuric acid.
Claim 14
Dependent Claim
65 words
The method of claim 1 including: after the growth of said p type GaAs cap layer, growing a second n type layer on said p type GaAs cap layer, said second n type layer comprising a semiconductor material which can be selectively etched with an etchant that does not etch GaAs and, thereafter, cooling the wafer; and etching and removing said second n type layer.
Claim 15
Dependent Claim
18 words
The method of claim 12 including growing an n type AlGaInP layer as said second n type layer.
Claim 16
Dependent Claim
17 words
The method of claim 13 including selectively etching said second n type AlGaInP layer with hydrochloric acid.
Claim 17
Dependent Claim
35 words
The method of claim 13 including: successively growing said second n type AlGaInP layer and a second GaAs layer; and selectively etching and removing said second GaAs layer and said second n type AlGaInP layer.
Claim 18
Dependent Claim
20 words
The method of claim 15 including selectively etching said second GaAs layer with one of tartaric acid and sulfuric acid.
Claim 19
Independent Claim
261 words
A method for manufacturing a semiconductor laser diode producing visible light and including a p type AlGaInP cladding layer on an active layer, said method comprising: successively growing an n type AlGaInP cladding layer, a GaInP active layer, a p type AlGaInP cladding layer, a p type GaAs cap layer, a first n type AlGaInP layer, and a first GaAs layer on an n type GaAs substrate and, thereafter, cooling the wafer; selectively etching and removing said first GaAs layer and said first n type AlGaInP layer; forming a stripe-shaped insulating film pattern on a part of the p type GaAs cap layer; removing portions of said p type GaAs cap layer and said p type AlGaInP cladding layer by etching using said insulating film pattern as a mask to form a stripe-shaped ridge; using said insulating film pattern as a mask, selectively growing an n type GaAs current blocking layer on said p type AlGaInP cladding layer contacting opposite side walls of said ridge; removing said insulating film pattern; growing a p type GaAs contact layer on said p type GaAs cap layer and on said n type GaAs current blocking layer and, successively, growing a second n type AlGaInP layer and a second GaAs layer on said p type GaAs contact layer and, thereafter, cooling the wafer; selectively etching and removing said second GaAs layer and said second n type AlGaInP layer; forming a p side electrode on said p type GaAs contact layer and an n side electrode on the rear surface of said n type GaAs substrate.
Claim 20
Independent Claim
261 words
A method for manufacturing a semiconductor laser diode producing visible light and including a p type AlGaInP cladding layer on an active layer, said method comprising: successively growing an n type AlGaInP cladding layer, a GaInP active layer, a p type AlGaInP cladding layer, a p type GaAs cap layer, a first n type AlGaInP layer, and a first GaAs layer on an n type GaAs substrate and, thereafter, cooling the wafer; selectively etching and removing said first GaAs layer and said first n type AlGaInP layer; forming a stripe-shaped insulating film pattern on a part of the p type GaAs cap layer; removing portions of said p type GaAs cap layer and said p type AlGaInP cladding layer by etching using said insulating film pattern as a mask to form a stripe-shaped ridge; using said insulating film pattern as a mask, selectively growing an n type GaAs current blocking layer on said p type AlGaInP cladding layer contacting opposite side walls of said ridge; removing said insulating film pattern; growing a p type GaAs contact layer on said p type GaAs cap layer and on said n type GaAs current blocking layer and, successively, growing a second n type AlGaInP layer and a second GaAs layer on said p type GaAs contact layer and, thereafter, cooling the wafer; selectively etching and removing said second GaAs layer and said second n type AlGaInP layer; forming a p side electrode on said p type GaAs contact layer and an n side electrode on the rear surface of said n type GaAs substrate.
Claim 21
Dependent Claim
21 words
The method of claim 17 including adding Zn as a p type impurity dopant while growing said p type AlGaInP layer.
Claim 22
Dependent Claim
26 words
The method of claim 17 including cooling said semiconductor substrate in one of a hydrogen atmosphere, a nitrogen atmosphere, and a mixture of hydrogen and nitrogen.
Claim 23
Dependent Claim
36 words
The method of claim 17 including selectively etching said first and second n type AlGaInP layers with hydrochloric acid and selectively etching said first and second GaAs layers with one of tartaric acid and sulfuric acid.
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