US6028875A
Expired / Lapsed
US
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Buried heterostructure laser with quaternary current blocking layer
Assignee: Nortel Networks Ltd
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Filing: 1996-10-11
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Granted: 2000-02-22
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Expires: 2016-10-11
Abstract
Abstract The lateral confinement region provided on both sides of an active region stripe of a buried heterostructure laser is formed of an alloy of InGaAsP instead of the conventional Fe doped InP material. This results in much improved regrowth morphology while still achieving good current and light blocking properties.
Inventors
- 👤 Douglas Gordon Knight
- 👤 Chunmeng Wu
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 16:49
CPC Classifications
B; B82; B82Y; B82Y20/00; H; H01; H01S; H01S5/00; H01S5/20; H01S5/22; H01S5/227; H01S5/2205; H01S5/2206; H01S5/2207; H01S5/2209; H01S5/2275; H01S5/30; H01S5/34; H01S5/343; H01S5/34306; H01S5/34313; H01S5/3434
Claims Analysis
Total Claims: 25
Claim 1
Independent Claim
60 words
A buried heterostructure semiconductor laser in which an active region is contained in a stripe delineated on opposite sidewalls by a current and light blocking layer wherein the blocking layer is a doped InGaAsP alloy, the degree of doping and type of dopant rendering the blocking layer semi-insulating with a bandgap wavelength less than the lasing wavelength of the laser.
Claim 2
Dependent Claim
60 words
A buried heterostructure semiconductor laser in which an active region is contained in a stripe delineated on opposite sidewalls by a current and light blocking layer wherein the blocking layer is a doped InGaAsP alloy, the degree of doping and type of dopant rendering the blocking layer semi-insulating with a bandgap wavelength less than the lasing wavelength of the laser.
Claim 3
Dependent Claim
26 words
A laser according to claim 1 wherein the active region has opposite sidewalls which define at least a portion of the opposite sidewalls of the stripe.
Claim 4
Dependent Claim
24 words
A laser according to claim 2 wherein the laser is a distributed feedback laser having a grating in the stripe adjacent the active region.
Claim 5
Dependent Claim
32 words
A laser according to claim 1 wherein the laser is a distributed Bragg reflector laser having gratings extending adjacent opposite sidewalls of the active region, both gratings being contained in the stripe.
Claim 6
Dependent Claim
36 words
A laser according to claim 1 wherein the active region is formed as InGaAsP alloy layers formed on a substrate of InP and having a cladding layer of InP overlying the stripe and the blocking layer.
Claim 7
Dependent Claim
38 words
A laser according to claim 1 wherein the active region is formed as InGaAs alloy layers formed on a substrate of GaAs and having a cladding layer of AlGaAs or GaInP overlying the stripe and the blocking layer.
Claim 8
Dependent Claim
37 words
A laser according to claim 1 wherein the active region is formed as GaAs layers formed on a substrate of GaAs and having a cladding layer of AlGaAs or GaInP overlying the stripe and the blocking layer.
Claim 9
Dependent Claim
30 words
A laser according to claim 5 wherein the doped InGaAsP alloy of the blocking layer is selected to have a bandgap wavelength substantially in the range 1.0 to 1.15 μm.
Claim 10
Dependent Claim
30 words
A laser according to claim 6 wherein the doped InGaAsP alloy of the blocking layer is selected to have a bandgap wavelength substantially in the range 0.65 to 0.85 μm.
Claim 11
Dependent Claim
30 words
A laser according to claim 7 wherein the doped InGaAsP alloy of the blocking layer is selected to have a bandgap wavelength substantially in the range 0.65 to 0.85 μm.
Claim 12
Dependent Claim
26 words
A laser according to claim 1, wherein the doped InGaAsP alloy of the blocking layer is selected to have a bandgap wavelength of approximately 1.3 μm.
Claim 13
Dependent Claim
14 words
A laser according to claim 1, wherein the blocking layer is Fe-doped InGaAsP alloy.
Claim 14
Dependent Claim
14 words
A laser according to claim 2, wherein the blocking layer is Fe-doped InGaAsP alloy.
Claim 15
Dependent Claim
14 words
A laser according to claim 3, wherein the blocking layer is Fe-doped InGaAsP alloy.
Claim 16
Dependent Claim
14 words
A laser according to claim 4, wherein the blocking layer is Fe-doped InGaAsP alloy.
Claim 17
Dependent Claim
14 words
A laser according to claim 5, wherein the blocking layer is Fe-doped InGaAsP alloy.
Claim 18
Dependent Claim
14 words
A laser according to claim 6, wherein the blocking layer is Fe-doped InGaAsP alloy.
Claim 19
Dependent Claim
14 words
A laser according to claim 7, wherein the blocking layer is Fe-doped InGaAsP alloy.
Claim 20
Dependent Claim
14 words
A laser according to claim 8, wherein the blocking layer is Fe-doped InGaAsP alloy.
Claim 21
Dependent Claim
14 words
A laser according to claim 9, wherein the blocking layer is Fe-doped InGaAsP alloy.
Claim 22
Dependent Claim
14 words
A laser according to claim 10, wherein the blocking layer is Fe-doped InGaAsP alloy.
Claim 23
Dependent Claim
129 words
A buried heterostructure semiconductor laser comprising a substrate of heavily n-doped InP, an n-doped buffer layer on the substrate, a stripe etched into the buffer layer and containing in addition to an uppermost portion of the buffer layer, lower GRINSCH layers of InGaAsP alloy on the buffer layer, an active region of InGaAsP on the lower GRINSCH layers, upper GRINSCH layers on the active region and a p-doped InP cap layer on the upper GRINSCH layers, the stripe having opposite sidewalls delineated by a current and light blocking doped InGaAsP alloy layer, the degree of doping and type of dopant rendering the blocking layer semi-insulating with a bandgap wavelength less than the lasing wavelength of the laser, and a layer of InP overlying the stripe and the blocking layer.
Claim 24
Dependent Claim
129 words
A buried heterostructure semiconductor laser comprising a substrate of heavily n-doped InP, an n-doped buffer layer on the substrate, a stripe etched into the buffer layer and containing in addition to an uppermost portion of the buffer layer, lower GRINSCH layers of InGaAsP alloy on the buffer layer, an active region of InGaAsP on the lower GRINSCH layers, upper GRINSCH layers on the active region and a p-doped InP cap layer on the upper GRINSCH layers, the stripe having opposite sidewalls delineated by a current and light blocking doped InGaAsP alloy layer, the degree of doping and type of dopant rendering the blocking layer semi-insulating with a bandgap wavelength less than the lasing wavelength of the laser, and a layer of InP overlying the stripe and the blocking layer.
Claim 25
Dependent Claim
14 words
A laser according to claim 22, wherein the blocking layer is Fe-doped InGaAsP alloy.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 2003-02-21 | 2003-08-23 | 2004-02-22 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2007-02-21 | 2007-08-23 | 2008-02-22 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2011-02-21 | 2011-08-23 | 2012-02-22 | $7700.00 | Window Closed / Lapsed |