US4563764A
Expired / Lapsed
US
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Semiconductor laser device
Assignee: Hitachi Ltd
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Filing: 1983-09-13
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Granted: 1986-01-07
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Expires: 2003-09-13
Abstract
Abstract Disclosed is a semiconductor laser device having at least an optical confinement region which includes a first semiconductor layer, and second and third semiconductor layers holding the first semiconductor layer therebetween and having a greater band gap and a lower refractive index than those of the first semiconductor layer, the second and third semiconductor layers having conductivity types opposite to each other; characterized in that the relationship between a donor density (NDx1017 cm-3) of the n-conductivity type semiconductor layer in the second and third semiconductor layers and a proportion ( GAMMA n%) of an optical output existing in the n-conductivity type semiconductor layer relative to a total optical output of the laser is set at NDx GAMMA n>/=500. Noise characteristics are sharply improved.
Inventors
- 👤 Takao Kuroda
- 👤 Takashi Kajimura
- 👤 Yasutoshi Kashiwada
- 👤 Naoki Chinone
- 👤 Hirobumi Ouchi
- 👤 Tsukuru Ohtoshi
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 20:35
CPC Classifications
H; H01; H01S; H01S5/00; H01S5/20; H01S5/22; H01S5/223; H01S5/2232; H01S5/2234
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
186 words
In a semiconductor laser device having at least an optical confinement region which is formed on a predetermined substrate and which optical confinement region includes a semiconductor assembly comprising a first semiconductor layer, and second and third semiconductor layers holding said first semiconductor layer therebetween, said second and third semiconductor layers having a greater band gap and a lower refractive index than those of said first semiconductor layer and having conductivity types opposite to each other with one of said second and third layers being doped with a donor impurity to be of n-conductivity type; a first electrode which is formed on the substrate side of said laser device; and a second electrode which is formed on the semiconductor assembly side of said laser device, wherein a relationship between a donor density (N D ×10 17 cm -3 ) of the n-conductivity type semiconductor layer in said second or third semiconductor layers and a proportion (Γ n %) of an optical output existing in said n-conductivity type semiconductor layer relative to a total optical output of said laser is set at N D ×Γ n ≧500.
Claim 2
Dependent Claim
186 words
In a semiconductor laser device having at least an optical confinement region which is formed on a predetermined substrate and which optical confinement region includes a semiconductor assembly comprising a first semiconductor layer, and second and third semiconductor layers holding said first semiconductor layer therebetween, said second and third semiconductor layers having a greater band gap and a lower refractive index than those of said first semiconductor layer and having conductivity types opposite to each other with one of said second and third layers being doped with a donor impurity to be of n-conductivity type; a first electrode which is formed on the substrate side of said laser device; and a second electrode which is formed on the semiconductor assembly side of said laser device, wherein a relationship between a donor density (N D ×10 17 cm -3 ) of the n-conductivity type semiconductor layer in said second or third semiconductor layers and a proportion (Γ n %) of an optical output existing in said n-conductivity type semiconductor layer relative to a total optical output of said laser is set at N D ×Γ n ≧500.
Claim 3
Dependent Claim
36 words
In a semiconductor laser device according to claim 1, wherein the refractive index of said n-conductivity type semiconductor layer in said second and third semiconductor layers is higher than that of the p-conductivity type semiconductor layer.
Claim 4
Dependent Claim
21 words
In a semiconductor laser device according to claim 1, wherein a doping impurity of said n-conductivity type semiconductor layer is Te.
Claim 5
Dependent Claim
21 words
In a semiconductor laser device according to claim 2, wherein a doping impurity of said n-conductivity type semiconductor layer is Te.
Claim 6
Dependent Claim
45 words
In a semiconductor laser device according to claim 1, wherein said optical confinement region of said laser device has a laser cavity length within a range of 210-250 μm and wherein the width of said first semiconductor layer is within a range of 1-4 μm.
Claim 7
Dependent Claim
45 words
In a semiconductor laser device according to claim 1, wherein said optical confinement region of said laser device has a laser cavity length within a range of 400-440 μm and wherein the width of said first semiconductor layer is within a range of 1-4 μm.
References Cited (Backward Citations)
US4328469A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1989-01-06 | 1989-07-08 | 1990-01-07 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1993-01-06 | 1993-07-08 | 1994-01-07 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1997-01-06 | 1997-07-08 | 1998-01-07 | $7700.00 | Window Closed / Lapsed |