EP0215298A2
Expired / Lapsed
EP
⏱️ 0.0 years remaining
Semiconductor laser
Assignee: Hitachi Ltd
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Filing: 1986-08-12
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Granted: —
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Expires: 2006-08-12
Abstract
Abstract A semiconductor laser having such a structure that a laser structure including a laser active region (3) of multi quantum well structure, cladding layers (2; 4, l5) and a cap layer (5) is formed on a substrate (l), is disclosed in which both end regions of the laser active region in the quantum well layer is converted into mixed crystal by impurity induced intermixing so that a multi quantum well active region is sandwiched between mixed crystal regions (6, 7; 12, l3), and impurity diffused regions (8, 9; 15, l6) are formed between the surface of the crystal and the mixed crystal regions, to form a current path and to inject carriers into the multi quantum well region in a direction parallel to the laser active layer. Thus, the semiconductor laser can modulate laser oscillation at a very high frequency, and moreover is readily fabricated or integrated.
Inventors
- 👤 Tadashi Fukuzawa
- 👤 Naoki Chinone
- 👤 Kazuhisa Uomi
- 👤 Takashi Kajimura
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-10-26 20:34
CPC Classifications
H; H01; H01S; H01S3/00; B; B82; B82Y; B82Y20/00; H01S5/00; H01S5/04; H01S5/042; H01S5/0421; H01S5/0422; H01S5/0424; H01S5/20; H01S5/02; H01S5/0206; H01S5/0208; H01S5/2054; H01S5/2059; H01S5/30; H01S5/34; H01S5/343; H01S5/34313; H01S5/3432
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
198 words
A semiconductor laser comprising: a semi-insulative substrate (l); and a laser structure formed on said substrate and including an undoped laser active layer (3) having a quantum well structure and at least two undoped semiconductor layers (2; 4, l4), said laser active layer being sandwiched between said semiconductor layers, each of said semiconductor layers having an energy band gap larger than the energy band gap of a quantum well layer of said quantum well structure, regions of said laser active layer on both sides of that region thereof which serves as a laser active region and is extended in the lengthwise direction of a laser cavity, being converted into a mixed crystal by impurity induced intermixing based upon selective impurity doping, one of the mixed crystal regions being doped with an impurity so as to form a p-type region (7, l3), the other mixed crystal region being doped with another impurity so as to form an n-type region (6, l2), said laser structure including means (6, 7, 8, 9: l2, l3, l5, l6) for injecting carriers into said laser active region which is sandwiched between said mixed crystal regions, in a direction parallel to said laser active layer.
Claim 2
Dependent Claim
198 words
A semiconductor laser comprising: a semi-insulative substrate (l); and a laser structure formed on said substrate and including an undoped laser active layer (3) having a quantum well structure and at least two undoped semiconductor layers (2; 4, l4), said laser active layer being sandwiched between said semiconductor layers, each of said semiconductor layers having an energy band gap larger than the energy band gap of a quantum well layer of said quantum well structure, regions of said laser active layer on both sides of that region thereof which serves as a laser active region and is extended in the lengthwise direction of a laser cavity, being converted into a mixed crystal by impurity induced intermixing based upon selective impurity doping, one of the mixed crystal regions being doped with an impurity so as to form a p-type region (7, l3), the other mixed crystal region being doped with another impurity so as to form an n-type region (6, l2), said laser structure including means (6, 7, 8, 9: l2, l3, l5, l6) for injecting carriers into said laser active region which is sandwiched between said mixed crystal regions, in a direction parallel to said laser active layer.
Claim 3
Dependent Claim
31 words
A semiconductor laser according to Claim l, wherein said carrier injection means includes means (8, 9; 15, l6) for supplying a current to said mixed crystal regions (6, 7; 12, l3).
Claim 4
Dependent Claim
33 words
A semiconductor laser according to Claim l, wherein said substrate (l) is made of InP, and said laser active layer (3) having a multi quantum well structure comprises alternate GaInAs and AlInAs layers.
Claim 5
Dependent Claim
33 words
A semiconductor laser according to Claim l, wherein said substrate (l) is made of GaAs, and said laser active layer (3) having a multi quantum well structure comprises alternate GaAlAs and AlAs layers.
Claim 6
Dependent Claim
34 words
A semiconductor laser according to Claim 2, wherein said current supplying means includes impurity doped regions (8, 9; 15, l6), each of which is formed by one of impurity diffusion and impurity ion implantation.
References Cited (Backward Citations)
No citation records indexed.
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