Patent EP0477013A2 successfully refreshed from Google Patents.
EP0477013A2
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EP
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Method of producing a semiconductor laser
Assignee: Mitsubishi Electric Corp
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Filing: 1991-09-19
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Granted: —
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Expires: 2011-09-19
Abstract
Abstract A semiconductor laser includes a first conductivity type semiconductor substrate (1); a first conductivity type semiconductor first cladding layer (2) disposed on the substrate (1); a semiconductor active layer (3) disposed on the first cladding layer (2); a second conductivity type semiconductor second cladding layer (4a) disposed on the active layer (3); a current concentration and collection structure for confining current flow to part of the active layer (3) comprising a second conductivity type ridge structure (10) disposed on the second cladding layer (4a) and a first conductivity type semiconductor current blocking layer (7) disposed directly on the second cladding layer (4a) and adjacent to and contacting the ridge structure (10), the ridge structure including a semiconductor etch stopping layer (90) different in composition from and disposed on the second cladding layer (4a) and a second conductivity type semiconductor third cladding layer (4b) disposed on and different in composition from the etch stopping layer (90); and first and second electrodes (15,16) respectively disposed on the substrate (1) and the current concentration and collection structure. A method of making a semiconductor laser includes successively growing on a first conductivity type semiconductor substrate (1) a first conductivity type semiconductor cladding layer (2), a semiconductor active layer (3), a second conductivity type semiconductor second cladding layer (4a), a semiconductor etch stopping layer (90), and a second conductivity type semiconductor third cladding layer (4b); masking a portion of the third cladding layer (4b) and etching the third cladding layer to produce a mesa (10) and expose part of the etch stopping layer, the etch stopping layer preventing etching of the second cladding layer; removing the exposed part of the etch stopping layer, thereby exposing part of the second cladding layer (4a); growing a first conductivity type semiconductor current blocking layer (7) on the second cladding layer adjacent to and in contact with the mesa; growing a second conductivity type semiconductor contacting layer (8) on the current blocking layer (7) and the mesa (10); forming first and second electrodes (15,16) on the substrate and contacting layer, respectively; and forming opposed facets (17,18) transverse to the mesa. <IMAGE> <IMAGE>
Inventors
- 👤 Satoshi C/O Mitsubishi Denki K.K. Arimoto
- 👤 Naohito C/O Mitsubishi Denki K.K. Yoshida
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-07 03:11
CPC Classifications
H; H10; H10H; H10H20/00; H10H20/01; H10H20/011; H10H20/013; H01; H01S; H01S5/00; H01S5/20; H01S5/22; H01S5/223; H01S5/2231; H01S5/2054; H01S5/2081; H01S5/209
Claims Analysis
Total Claims: 18
Claim 1
Independent Claim
154 words
A semiconductor laser comprising: a first conductivity type semiconductor substrate; a first conductivity type semiconductor first cladding layer disposed on the substrate; a semiconductor active layer disposed on the first cladding layer; a second conductivity type semiconductor second cladding layer disposed on the active layer; current concentration and collection means for confining current flow to part of the active layer comprising a second conductivity type ridge structure disposed on the second cladding layer and a first conductivity type semiconductor current blocking layer disposed directly on the second cladding layer and adjacent to and contacting the ridge structure, the ridge structure including a semiconductor etch stopping layer different in composition from and disposed on the second cladding layer and a second conductivity type semiconductor third cladding layer disposed on and different in composition from the etch stopping layer; and first and second electrodes respectively disposed on the substrate and the current concentration and collection means.
Claim 2
Dependent Claim
163 words
A semiconductor laser comprising: a first conductivity type semiconductor substrate; a first conductivity type semiconductor first cladding layer disposed on the substrate; a semiconductor active layer disposed on the first cladding layer; a second conductivity type semiconductor second cladding layer disposed on the active layer; current concentration and collection means for confining current flow to part of the active layer comprising a groove structure disposed on the second cladding layer including a first conductivity type semiconductor current blocking layer having a groove extending to the second cladding layer, a semiconductor etch stopping layer disposed between, in contact with, and different in composition from the current blocking layer and the second cladding layer, and a second conductivity type semiconductor third cladding layer disposed on the current blocking layer and on and in direct contact with the second cladding layer in the groove in the current blocking layer; and first and second electrodes respectively disposed on the substrate and the current concentration and collection means.
Claim 3
Dependent Claim
168 words
A semiconductor laser comprising: a first conductivity type semiconductor substrate; a first conductivity type semiconductor first cladding layer disposed on the substrate; a semiconductor active layer disposed on the first cladding layer; a first electrode disposed on the substrate; and current concentration and collection means for confining current flow to part of the active layer; and a second electrode disposed on the current concentration and collection means wherein the current concentration and collection means includes a regrowth interface on part of the second cladding layer, a semiconductor etch stopping layer disposed on part of and different in composition from the second cladding layer, but not disposed on the regrowth interface part of the second cladding layer, a second conductivity type semiconductor third cladding layer in electrical communication with the second cladding layer, and a first conductivity type semiconductor current blocking layer in contact with the third cladding layer for blocking the flow of current between the first and second electrodes except through the part of the active layer.
Claim 4
Dependent Claim
33 words
A semiconductor laser according to any of claims 1 to 3, including a second conductivity type semiconductor contacting layer disposed between and contacting the second electrode and the current concentration and collection means.
Claim 5
Dependent Claim
31 words
A semiconductor laser according to claims 1 and 4 wherein the ridge structure includes a second conductivity type semiconductor transition layer disposed between the third cladding layer and the contacting layer.
Claim 6
Dependent Claim
30 words
A semiconductor laser according to any of claims 1 to 3, wherein the first, second, and third cladding layers are AlGaInP and the active and etch stopping layers are GaInP.
Claim 7
Dependent Claim
27 words
A semiconductor laser according to claim 6 wherein the etch stopping layer has a thickness between the second and third cladding layers of four to ten nanometers.
Claim 8
Dependent Claim
45 words
A semiconductor laser according to any of claims 1 to 3 wherein the first, second, and third cladding layers are Al x Ga 1-x As, the active layer is Al y Ga 1-y As, where x > y, and the etch stopping layer is GaInP.
Claim 9
Dependent Claim
27 words
A semiconductor laser according to claim 8 wherein the etch stopping layer has a thickness between the second and third cladding layers of one to ten nanometers.
Claim 10
Dependent Claim
61 words
A semiconductor laser according to claim 3 wherein the current concentration and collection means includes a ridge structure disposed on and in contact with the second cladding layer and comprising the third cladding layer and the etch stopping layer and the current blocking layer is in direct contact with the regrowth interface of the second cladding layer outside the ridge structure.
Claim 11
Dependent Claim
71 words
A semiconductor laser according to claim 3 wherein the current concentration and collection means includes a groove extending through the current blocking layer to the regrowth interface on the second cladding layer, the third cladding layer is in direct contact with the regrowth interface of the second cladding layer, and the etch stopping layer is disposed between and in direct contact with the current blocking layer and the second cladding layer.
Claim 12
Independent Claim
170 words
A method of making a semiconductor laser comprising: successively growing on a first conductivity type semiconductor substrate a first conductivity type semiconductor cladding layer, a semiconductor active layer, a second conductivity type semiconductor second cladding layer, a semiconductor etch stopping layer, and a second conductivity type semiconductor third cladding layer different in composition from the etch stopping layer; masking a portion of the third cladding layer and etching the third cladding layer to produce a mesa and expose part of the etch stopping layer, the etch stopping layer preventing etching of the second cladding layer; removing the exposed part of the etch stopping layer, thereby exposing part of the second cladding layer; growing a first conductivity type semiconductor current blocking layer on the second cladding layer adjacent to and in contact with the mesa; growing a second conductivity type semiconductor contacting layer on the current blocking layer and the mesa; forming first and second electrodes on the substrate and contacting layer, respectively; and forming opposed facets transverse to the mesa.
Claim 13
Independent Claim
156 words
A method of making a semiconductor laser comprising: successively growing on a first conductivity type semiconductor substrate a first conductivity type semiconductor cladding layer, a semiconductor active layer, a second conductivity type semiconductor second cladding layer, a semiconductor etch stopping layer, and a first conductivity type semiconductor current blocking layer different in composition from the etch stopping layer; etching a groove through the current blocking layer, thereby exposing a part of the etch stopping layer, the etch stopping layer preventing exposure of the second cladding layer; removing the exposed part of the etch stopping layer, thereby exposing part of the second cladding layer; successively growing on the exposed part of the second cladding layer and on the current blocking layer a second conductivity type semiconductor third cladding layer and a second conductivity type semiconductor contacting layer; forming first and second electrodes on the substrate and contacting layer, respectively; and forming opposed facets transverse to the groove.
Claim 14
Independent Claim
24 words
A method according to either of claims 12 or 13 including removing the exposed part of the etch stopping layer by thermally decomposing it.
Claim 15
Independent Claim
37 words
A method according to claims 12 and 14 including growing a second conductivity type semiconductor transition layer on the third cladding layer before forming the mesa and including a portion of the transition layer within the mesa.
Claim 16
Independent Claim
43 words
A method according to either of claims 12 or 13 including growing AlGaInP as the first, second, and third cladding layers, growing GaInP as the active layer,and growing GaInP as the etch stopping layer to a thickness of approximately four to ten nanometers.
Claim 17
Independent Claim
56 words
A method according to either of claims 12 or 13 including growing Al x Ga 1-x As as the first, second, and third cladding layer, growing Al y Ga 1-y As, where x > y, as the active layer, and growing GaInP as the etch stopping layer to a thickness of about one to ten nanometers.
Claim 18
Independent Claim
30 words
A method according to either of claims 16 or 17 including removing the exposed part of the GaInP etch stopping layer by thermally decomposing it at a temperature above 700°C.
References Cited (Backward Citations)
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