EP0388149A2
Expired / Lapsed
EP
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A semiconductor laser device and a method for the production of the same
Assignee: Sharp Corp
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Filing: 1990-03-13
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Granted: —
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Expires: 2010-03-13
Abstract
Abstract A semiconductor laser device is disclosed which emits laser light from an end facet. The semiconductor laser device comprises a multi-layered structure (12) formed on a semiconductor substrate (11), the multi-layered structure (12) having an active layer (16) for laser oscillation, and a pair of cleavage planes (101) on the side of the multi-layered structure (12), wherein a graded-band-gap layer (18) is formed on at least one of the cleavage planes (101), the graded-band-gap layer (18) having a forbidden band gap which increases gradually with an increase in the distance from the cleavage plane (101) and the surface of the graded-band-gap layer (18) constituting the end facet.
Inventors
- 👤 Hidenori Kawanishi
- 👤 Hiroshi Hayashi
- 👤 Taiji Morimoto
- 👤 Shinji Kaneiwa
- 👤 Nobuyuki Miyauchi
- 👤 Seiki Yano
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-10-27 19:40
CPC Classifications
H; H01; H01S; H01S5/00; H01S5/02; H01S5/028; H01S5/0281; H01S5/0201; H01S5/10; H01S5/16; H01S5/164; H01S5/166
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
93 words
In a semiconductor laser device which emits laser light from an end facet, comprising a multi-layered structure formed on a semiconductor substrate, said multi-layered structure having an active layer for laser oscillation, and a pair of cleavage planes on the side of the multi-layered structure, the device wherein a graded-band-gap layer is formed on at least one of said cleavage planes said graded-band-gap layer having a forbidden band gap which increases gradually with an increase in the distance from said cleavage plane, and the surface of said graded-band-gap layer constituting said end facet.
Claim 2
Dependent Claim
93 words
In a semiconductor laser device which emits laser light from an end facet, comprising a multi-layered structure formed on a semiconductor substrate, said multi-layered structure having an active layer for laser oscillation, and a pair of cleavage planes on the side of the multi-layered structure, the device wherein a graded-band-gap layer is formed on at least one of said cleavage planes said graded-band-gap layer having a forbidden band gap which increases gradually with an increase in the distance from said cleavage plane, and the surface of said graded-band-gap layer constituting said end facet.
Claim 3
Dependent Claim
37 words
A semiconductor laser device according to claim 1, wherein said active layer is made of Ga 1-x Al x As (0 ≦ x ≦ 1) and said graded-band-gap layer is made of Ga 1-y Al y As.
Claim 4
Dependent Claim
35 words
A semiconductor laser device according to claim 2, wherein the Al mole fraction y of said graded-band-gap layer increases from the cleavage plane to the end facet in accordance with the linear or parabolic distribution.
Claim 5
Dependent Claim
34 words
A semiconductor laser device according to claim 3, wherein the Al mole fraction y at the cleavage plane between the active layer and the graded-band-gap layer is equal to the Al mole fraction x.
Claim 6
Dependent Claim
34 words
A semiconductor laser device according to claim 3, wherein the Al mole fraction y at the cleavage plane between the active layer and the graded-band-gap layer is greater than the Al mole fraction x.
Claim 7
Dependent Claim
34 words
A semiconductor laser device according to claim 3, wherein the Al mole fraction y at the cleavage plane between the active layer and the graded-band-gap layer is smaller than the Al mole fraction x.
Claim 8
Dependent Claim
82 words
A method for the production of a semiconductor laser device of claim 1, comprising forming a multi-layered structure on a semiconductor substrate, said multi-layered structure having an active layer for laser oscillation; cleaving the substrate together with the multi-layered structure to form a laser cavity between cleavage planes; and forming a graded-band-gap layer on at least one of said cleavage planes, said graded-band-gap layer having a forbidden band gap which increases gradually with an increase in the distance from said cleavage plane.
Claim 9
Dependent Claim
16 words
A method according to claim 7, wherein said graded-band-gap layer is grown by vapor phase epitaxy.
References Cited (Backward Citations)
No citation records indexed.
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