Patent EP0358227A2 successfully refreshed from Google Patents.
EP0358227A2
Expired / Lapsed
EP
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Semiconductor laser device
Assignee: Toshiba Corp
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Filing: 1989-09-08
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Granted: —
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Expires: 2009-09-08
Abstract
Abstract A semiconductor laser device comprises a substrate (1) formed of elements of the III-IV groups and having one conductivity type, a lower clad layer (3) formed on the substrate (1) and having the same conductivity type as that of the substrate (1), and an upper clad layer (5) formed on the lower clad layer (3) and having a conductivity type opposite to that of the lower clad layer (3). A waveguide layer having a large refractive index is formed within the lower clad layer (3) by decreasing the band gap of the upper clad layer (5). The light generated in an activation layer (4) is guided to the lower clad layer (3), so as to suppress adverse effects which the upper clad layer (5) may have on element characteristics.
Inventors
- 👤 Hideaki C/O Intellectual Property Div. Kinoshita
- 👤 Naohiro C/O Intellectual Property Div. Shimada
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-08 11:29
CPC Classifications
H; H01; H01S; H01S5/00; H01S5/20; H01S5/22; H01S5/223; H01S5/2231; H01S5/2004; H01S5/30; H01S5/32; H01S5/3211; H01S5/3213; H01S5/323; H01S5/32308; H01S5/32325
Claims Analysis
Total Claims: 13
Claim 1
Independent Claim
107 words
A semiconductor laser device comprising: a substrate (1) formed of elements of III-IV groups and being of one conductivity type; a lower clad layer (3) formed on said substrate (1), said lower clad layer (3) being formed of a four-element mixed crystal and being of said one conductivity type; an upper clad layer (5) formed on said lower clad layer (3), with an activation layer (4) interposed, said upper clad layer (5) being formed of a four-element mixed crystal and being of a conductivity type opposite to said one conductivity type; and an asymmetric double hetero structure defined by said upper and lower clad layers (5, 3).
Claim 2
Dependent Claim
107 words
A semiconductor laser device comprising: a substrate (1) formed of elements of III-IV groups and being of one conductivity type; a lower clad layer (3) formed on said substrate (1), said lower clad layer (3) being formed of a four-element mixed crystal and being of said one conductivity type; an upper clad layer (5) formed on said lower clad layer (3), with an activation layer (4) interposed, said upper clad layer (5) being formed of a four-element mixed crystal and being of a conductivity type opposite to said one conductivity type; and an asymmetric double hetero structure defined by said upper and lower clad layers (5, 3).
Claim 3
Dependent Claim
38 words
A semiconductor laser device according to claim 1, characterized in that said asymmetric double hetero structure is formed by providing the upper clad layer (5) with a refractive index larger than that of the lower clad layer (3).
Claim 4
Dependent Claim
33 words
A semiconductor laser device according to claim l, characterized in that said asymmetric double hetero structure is formed by providing the upper and lower clad layers (5, 3) with predetermined thermal conductivities respectively.
Claim 5
Dependent Claim
26 words
A semiconductor laser device according to claim 1, characterized in that the four-element mixed crystals of said upper and lower clad layers (5, 3) are InGaAℓP.
Claim 6
Dependent Claim
31 words
A semiconductor laser device according to claim 4, characterized in that the four-element mixed crystal of said lower clad layer (3) is In 1-y (Ga 1-x A ℓx ) y P.
Claim 7
Dependent Claim
31 words
A semiconductor laser device according to claim 5, characterized in that the four-element mixed crystal of said lower clad layer (3) is In 0.5 (Ga 0.3 Aℓ 0.7 ) 0.5 P.
Claim 8
Dependent Claim
52 words
A semiconductor laser device according to claim 6, characterized in that the four-element mixed crystal of said upper clad layer (5) is In 0.5 (Ga 0.5 Aℓ 0.5 ) 0.5 P, and the four-element mixed crystal of said lower clad layer (3) is In 0.5 (Ga 0.3 Aℓ 0.7 ) 0.5 P.
Claim 9
Dependent Claim
25 words
A semiconductor laser device according to claim 1, characterized in that said substrate (1), formed of elements of the III-IV groups, is of an n-type.
Claim 10
Dependent Claim
59 words
A semiconductor laser device according to claim 4, characterized in that a current supply-facilitating layer (2) is formed between said substrate (1), formed of elements of the III-IV groups, and said lower clad layer (3), said current supply-facilitating layer (2) being formed of InGaP and being of the same conductivity type as that of said lower clad layer (3).
Claim 11
Dependent Claim
46 words
A semiconductor laser device according to claim 4, characterized in that a current-blocking layer (6) is formed on said upper clad layer (5), said current-blocking layer (6) being formed of GaAs and being of a conductivity type opposite to that of said upper clad layer (5).
Claim 12
Dependent Claim
20 words
A semiconductor laser device according to claim 4, characterized in that said activation layer (4) is formed of undoped InGaP.
Claim 13
Dependent Claim
26 words
A semiconductor laser device according to claim 1, characterized in that said substrate (1), formed of elements of the III-IV groups, is a GaAs substrate (1).
References Cited (Backward Citations)
No citation records indexed.
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