EP0208209A2
Expired / Lapsed
EP
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A buried heterostructure semiconductor laser
Assignee: NEC Corp
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Filing: 1986-06-26
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Granted: —
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Expires: 2006-06-26
Abstract
Abstract An improved buried heterostructure semiconductor laser comprises high resistive burying layers positioned at both sides of an active region so that the high speed modulation is possible to be performed and the higher quantum efficiency is obtained for the reason why the capacitance and leakage current are diminished. A further improved buried heterostructure semiconductor laser comprises spacer layers between an active region and respective high resistive burying layers so that the reliability is maintained to be high for the reason why the diffusion of an impurity is avoided from the respective high resistive burying layers to the active region. Further, an improved process for the fabrication of a buried heterostructure semiconductor laser comprises steps of forming mesa stripe including an active region on the upper portion of a double heterostructure and forming high resistive burying layers to be positioned at both sides of the active region.
Inventors
- 👤 Shigeo Sugou
- 👤 Tomoo Yanase
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-10-27 04:52
CPC Classifications
H; H01; H01S; H01S5/00; H01S5/20; H01S5/22; H01S5/227; H01S5/2275; H01S5/2277; H01S5/30; H01S5/305; H01S5/3072
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
113 words
1 . A buried heterostructure semiconductor laser composed of compound semiconductor material and comprising a double heterostructure including an active region and semiconductor layers positioned on both surfaces of said active region, each of said semiconductor layers having a forbidden band width which is different from that of said active region, and burying layers positioned at both sides of said double heterostructure, each of said burying layers having a refractive index lower than that of said active region and having a forbidden band width larger than that of said active region, wherein each of said burying layers comprises a high resistive semiconductor layer including at least one impurity which occupies deep level therein.
Claim 2
Dependent Claim
113 words
1 . A buried heterostructure semiconductor laser composed of compound semiconductor material and comprising a double heterostructure including an active region and semiconductor layers positioned on both surfaces of said active region, each of said semiconductor layers having a forbidden band width which is different from that of said active region, and burying layers positioned at both sides of said double heterostructure, each of said burying layers having a refractive index lower than that of said active region and having a forbidden band width larger than that of said active region, wherein each of said burying layers comprises a high resistive semiconductor layer including at least one impurity which occupies deep level therein.
Claim 3
Dependent Claim
30 words
A buried heterostructure semiconductor laser according to claim 1, wherein each of said burying layers further comprises a spacer layer positioned between said active region and said high resistive layer.
Claim 4
Dependent Claim
25 words
A buried heterostructure semiconductor laser according to claim 1 or 2. wherein said active region is narrowed to have constricted portions at both sides thereof.
Claim 5
Dependent Claim
26 words
A buried heterostructure semiconductor laser according to any of claims 1 to 3. wherein said impurity comprises an impurity selected from Fe, Cr, V, Mn, Co.
Claim 6
Dependent Claim
150 words
A process for the fabrication of a buried heterostructure semiconductor laser comprising steps of forming a double heterostructure including an active region and semiconductor layers positioned on both surfaces of said active region, the forbidden band width of said semiconductor layers being different from that of said active region, forming mesa stripe including said active region in a predetermined direction on the upper portion of said double heterostructure, and forming burying layers respectively to be positioned at both sides of said mesa stripe, wherein said step of forming said burying layers comprises the first step of forming spacer layers along the side surfaces of said active region, each of said spacer layers being composed of a semiconductor layer having no impurity which occupies deep level, and the second step of forming high resistive layers each composed of a semiconductor layer having at least one impurity which occupies deep level therein.
Claim 7
Dependent Claim
150 words
A process for the fabrication of a buried heterostructure semiconductor laser comprising steps of forming a double heterostructure including an active region and semiconductor layers positioned on both surfaces of said active region, the forbidden band width of said semiconductor layers being different from that of said active region, forming mesa stripe including said active region in a predetermined direction on the upper portion of said double heterostructure, and forming burying layers respectively to be positioned at both sides of said mesa stripe, wherein said step of forming said burying layers comprises the first step of forming spacer layers along the side surfaces of said active region, each of said spacer layers being composed of a semiconductor layer having no impurity which occupies deep level, and the second step of forming high resistive layers each composed of a semiconductor layer having at least one impurity which occupies deep level therein.
Claim 8
Dependent Claim
36 words
A process for the fabrication of a buried heterostructure semiconductor laser according to claim 5, further comprising a step of forming constricted portions at both sides of said active region by selective etching of said mesa.
References Cited (Backward Citations)
No citation records indexed.
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