US4329660A
Expired / Lapsed
US
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Semiconductor light emitting device
Assignee: Fujitsu Ltd
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Filing: 1980-02-11
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Granted: 1982-05-11
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Expires: 2000-02-11
Abstract
Abstract In a semiconductor light emitting device, a buried layer of a semiconductor is selectively formed in at least one of a first and a second clad layers in order to determine a light emitting region by the configuration of the buried layer of the semiconductor. The buried layer of the semiconductor has a conductivity type which is opposite to the conductivity type of the surrounding clad layer and an index of refraction which is different from the index of refraction of the surrounding clad layer.
Inventors
- 👤 Mitsuhiro Yano
- 👤 Hiroshi Nishi
- 👤 Masahito Takusagawa
- 👤 Yorimitsu Nishitani
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 12:27
CPC Classifications
H; H01; H01S; H01S5/00; H01S5/10; H01S5/16; H01S5/164; H10; H10H; H10H20/00; H10H20/80; H10H20/81; H10H20/811; H10H20/822; H10H20/824
Claims Analysis
Total Claims: 19
Claim 1
Independent Claim
134 words
A semiconductor light emitting device comprising, a semiconductor substrate, a first clad layer of semiconductor formed on the semiconductor substrate, an active layer of semiconductor formed on the first clad layer, a second clad layer of semiconductor formed on the active layer, electrodes arranged on the second clad layer and on the bottom surface of the semiconductor substrate, respectively, and at least one buried layer of semiconductor buried in at least one of said clad layers, each buried layer having a conductivity type opposite to the conductivity type of the clad layer in which it is buried and an index of refraction different from the index of refraction of the clad layer in which it is buried, each said buried layer having a configuration for determining a light emitting region of said active layer.
Claim 2
Dependent Claim
134 words
A semiconductor light emitting device comprising, a semiconductor substrate, a first clad layer of semiconductor formed on the semiconductor substrate, an active layer of semiconductor formed on the first clad layer, a second clad layer of semiconductor formed on the active layer, electrodes arranged on the second clad layer and on the bottom surface of the semiconductor substrate, respectively, and at least one buried layer of semiconductor buried in at least one of said clad layers, each buried layer having a conductivity type opposite to the conductivity type of the clad layer in which it is buried and an index of refraction different from the index of refraction of the clad layer in which it is buried, each said buried layer having a configuration for determining a light emitting region of said active layer.
Claim 3
Dependent Claim
36 words
The device of claim 1, wherein the index of refraction of at least one buried layer is greater by more than a predetermined value than the index of the clad layer in which it is buried.
Claim 4
Dependent Claim
27 words
The device of claim 2, wherein the index of refraction of at least one buried layer is smaller than the index of refraction of the active layer.
Claim 5
Dependent Claim
32 words
The device of claim 1, wherein the index of refraction of at least one buried layer is smaller than the index of refraction of the clad layer in which it is buried.
Claim 6
Dependent Claim
18 words
The device of claim 1 having a double heterostructure and a stripe configuration for said light emitting region.
Claim 7
Dependent Claim
24 words
The device of claim 1, wherein an ohmic contact layer is arranged on said second clad layer under the respective one(s) of said electrodes.
Claim 8
Dependent Claim
22 words
A semiconductor light emitting device as defined in claim 1, wherein the active layer has a thickness of 0.05 through 0.3 μm.
Claim 9
Dependent Claim
22 words
A semiconductor light emitting device as defined in claim 1, wherein the buried layer has a thickness of 0.2 through 2 μm.
Claim 10
Dependent Claim
33 words
A semiconductor light emitting device as defined in claim 1, wherein the portion of the clad layer between the active layer and the buried layer has a thickness of 0.2 through 0.5 μm.
Claim 11
Dependent Claim
21 words
The device of claim 1, wherein the first clad layer has a thickness in the range from 1 to 5 μm.
Claim 12
Dependent Claim
21 words
The device of claim 1, wherein the second clad layer has a thickness in the range from 2 to 5 μm.
Claim 13
Dependent Claim
35 words
The device of claim 1 or 2, the semiconductor substrate comprising InP, the first clad layer comprising InP, the active layer comprising InGaAsP, the second clad layer comprising InP and the buried layer comprising InGaAsP.
Claim 14
Dependent Claim
36 words
The device of claim 1, 2 or 3, the semiconductor substrate comprising GaAs, the first clad layer comprising GaAlAs, the active layer comprising GaAs, the second clad layer comprising GaAlAs and the buried layer comprising GaAlAs.
Claim 15
Dependent Claim
70 words
The device of claim 2 consisting of one of said buried layers, said one buried layer being buried in said second clad layer and having a higher index of refraction than said second clad layer, said first clad layer, active layer, second clad layer and buried layer having respective energy gaps Eg (1) to Eg (5), said energy gaps satisfying Eg (3)≦Eg (5), Eg (5)<Eg (2) and Eg (5)<Eg (4).
Claim 16
Dependent Claim
70 words
The device of claim 2, consisting of one of said buried layers, said one buried layer being buried in said second clad layer and having a lower index of refraction than said second clad layer, said first clad layer, active layer, second clad layer and buried layer having respective energy gaps Eg (1) to Eg (5), said energy gaps satisfying Eg (3)<Eg (2), Eg (3)<Eg (4) and Eg (4)<Eg (5).
Claim 17
Dependent Claim
128 words
A semiconductor light emitting device comprising a semiconductor substrate, a first clad layer of semiconductor formed on the semiconductor substrate, an active layer of semiconductor formed on the first clad layer, the active layer comprising a light emitting stripe portion a second clad layer of semiconductor formed on the active layer, electrodes arranged on the second clad layer and on the bottom surface of the semiconductor substrate, respectively, and at least one buried semiconductor layer in at least one of the first and the second clad layers, each said buried layer having conductivity type which is opposite to the conductivity type of the clad layer in which it is embedded and said buried layer(s) having a configuration to define said light emitting stripe portion of the active layer.
Claim 18
Dependent Claim
128 words
A semiconductor light emitting device comprising a semiconductor substrate, a first clad layer of semiconductor formed on the semiconductor substrate, an active layer of semiconductor formed on the first clad layer, the active layer comprising a light emitting stripe portion a second clad layer of semiconductor formed on the active layer, electrodes arranged on the second clad layer and on the bottom surface of the semiconductor substrate, respectively, and at least one buried semiconductor layer in at least one of the first and the second clad layers, each said buried layer having conductivity type which is opposite to the conductivity type of the clad layer in which it is embedded and said buried layer(s) having a configuration to define said light emitting stripe portion of the active layer.
Claim 19
Dependent Claim
41 words
The device of claim 16, wherein the length of said buried layer(s) along the ends of said stripe portion is in the range from 5 to 15% of the length of the buried layer along the sides of the stripe portion.
References Cited (Backward Citations)
US4033796A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1985-05-10 | 1985-11-09 | 1986-05-11 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1989-05-10 | 1989-11-09 | 1990-05-11 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1993-05-10 | 1993-11-09 | 1994-05-11 | $7700.00 | Window Closed / Lapsed |