US4288757A
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Semiconductor laser device
Assignee: Hitachi Ltd
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Filing: 1979-07-10
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Granted: 1981-09-08
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Expires: 1999-07-10
Abstract
Abstract In certain applications, it is desirable to have a semiconductor laser device having shorter wave lengths of oscillation than are possible with conventional semiconductor lasers. To accomplish this, a semiconductor laser device is formed having a double-hetero structure, which comprises a semiconductor substrate composed of a GaAsP crystal, a first cladding layer formed on the substrate and composed of a GaAlAsP crystal of one conducting type, an active layer formed on the first cladding layer and composed of GaInAsP crystal, and a second cladding layer formed on the active layer and composed of a GaAlAsP crystal of the conducting type reverse to that of the first cladding layer. The cladding layers disposed on both sides of the active layer have a lower refractivity and a larger band gap than the active layer.
Inventors
- 👤 Takashi Kajimura
- 👤 Motohisa Hirao
- 👤 Michiharu Nakamura
- 👤 Takao Kuroda
- 👤 Shigeo Yamashita
- 👤 Jun-Ichi Umeda
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 12:31
CPC Classifications
H; H10; H10H; H10H20/00; H10H20/80; H10H20/81; H10H20/811; H01; H01S; H01S5/00; H01S5/20; H01S5/22; H01S5/30; H01S5/32; H01S5/323; H01S5/32308; H10H20/822; H10H20/824; H01S5/32325
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
143 words
In a semiconductor laser device comprising a semiconductor substrate composed of GaAs t P l-t (0.54≦t<1.0), a first semiconductor layer of a first conducting type formed on the substrate and composed of Ga p Al 1-p As q P 1-q (0≦p≦0.91 and 0.47≦q≦1.0), a second semiconductor layer formed on said first semiconductor layer and composed of Ga y In 1-y As x P 1-x (0.52≦y≦1.0 and 0≦x≦1.0), a third semiconductor layer of a conducting type reverse to that of the first semiconductor layer, which is formed on said second semiconductor layer and is composed of Ga p' Al 1-p' As q' P 1-q' (0≦p'≦0.91 and 0.47≦q'≦1.0), said second semiconductor layer containing at least one optical confinement region having a higher refractivity than those of the first and third semiconductor and a band gap smaller than those of the first and third semiconductor layers.
Claim 2
Dependent Claim
143 words
In a semiconductor laser device comprising a semiconductor substrate composed of GaAs t P l-t (0.54≦t<1.0), a first semiconductor layer of a first conducting type formed on the substrate and composed of Ga p Al 1-p As q P 1-q (0≦p≦0.91 and 0.47≦q≦1.0), a second semiconductor layer formed on said first semiconductor layer and composed of Ga y In 1-y As x P 1-x (0.52≦y≦1.0 and 0≦x≦1.0), a third semiconductor layer of a conducting type reverse to that of the first semiconductor layer, which is formed on said second semiconductor layer and is composed of Ga p' Al 1-p' As q' P 1-q' (0≦p'≦0.91 and 0.47≦q'≦1.0), said second semiconductor layer containing at least one optical confinement region having a higher refractivity than those of the first and third semiconductor and a band gap smaller than those of the first and third semiconductor layers.
Claim 3
Dependent Claim
21 words
A device as set forth in claim 1 wherein the thickness of said second semiconductor layer is 0.05 to 3.0 μm.
Claim 4
Dependent Claim
175 words
A semiconductor laser device comprising a semiconductor substrate composed of GaAs t P 1-t (0.54≦t<1.0), a first semiconductor layer of a first conducting type formed on the substrate and composed of Ga p Al 1-p As q P 1-q (0≦p≦0.91 and 0.47≦q≦1.0), a second semiconductor layer formed on said first semiconductor layer and composed of Ga y In 1-y As x P 1-x (0.52≦y≦1.0 and 0≦x≦1.0), a third semiconductor layer of a conducting type reverse to that of the first semiconductor layer, which is formed on said second semiconductor layer and is composed of Ga p' Al 1-p' As q' P 1-q' (0≦p'≦0.91 and 0.47≦q'≦1.0), said second semiconductor layer containing at least one optical confinement region having a higher refractivity than those of the first and third semiconductor and a band gap smaller than those of the first and third semiconductor layers; a first electrode coupled to said third semiconductor layer; a second electrode coupled to said semiconductor substrate; and means, including said optical confinement region, for forming a resonant optical cavity for optical radiation.
Claim 5
Dependent Claim
175 words
A semiconductor laser device comprising a semiconductor substrate composed of GaAs t P 1-t (0.54≦t<1.0), a first semiconductor layer of a first conducting type formed on the substrate and composed of Ga p Al 1-p As q P 1-q (0≦p≦0.91 and 0.47≦q≦1.0), a second semiconductor layer formed on said first semiconductor layer and composed of Ga y In 1-y As x P 1-x (0.52≦y≦1.0 and 0≦x≦1.0), a third semiconductor layer of a conducting type reverse to that of the first semiconductor layer, which is formed on said second semiconductor layer and is composed of Ga p' Al 1-p' As q' P 1-q' (0≦p'≦0.91 and 0.47≦q'≦1.0), said second semiconductor layer containing at least one optical confinement region having a higher refractivity than those of the first and third semiconductor and a band gap smaller than those of the first and third semiconductor layers; a first electrode coupled to said third semiconductor layer; a second electrode coupled to said semiconductor substrate; and means, including said optical confinement region, for forming a resonant optical cavity for optical radiation.
Claim 6
Dependent Claim
21 words
A device as set forth in claim 3, wherein the thickness of said second semiconductor layer is 0.05 to 3.0 μm.
Claim 7
Dependent Claim
34 words
A device as set forth in claim 3, wherein said first electrode is coupled to said third semiconductor layer through a fourth semiconductor layer formed on said third semiconductor layer and composed of GaAsP.
Claim 8
Dependent Claim
36 words
A device as set forth in claim 1, 2, 3 or 4 wherein the difference of the band gap between the second semiconductor layer and the first and third semiconductor layers is at least 0.3 eV.
References Cited (Backward Citations)
No citation records indexed.
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| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
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| 3.5 Years (Year 4) | 1984-09-07 | 1985-03-09 | 1985-09-08 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1988-09-07 | 1989-03-09 | 1989-09-08 | $3760.00 | Window Closed / Lapsed |
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