Patent US4425650A successfully refreshed from Google Patents.
US4425650A
Expired / Lapsed
US
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Buried heterostructure laser diode
Assignee: NEC Corp
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Filing: 1981-04-10
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Granted: 1984-01-10
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Expires: 2001-04-10
Abstract
Abstract A buried heterostructure laser diode and method for making the same wherein an active layer is provided in a semiconductor region forming a mesa stripe, and, except for the top surface portion of the mesa stripe, the side surface portion of the mesa stripe and the remainder are covered by a current-blocking layer. Furthermore, a current-confining layer covers only this current-blocking layer, and a clad layer covers the current-blocking layer and the top surface portion of the mesa stripe.
Inventors
- 👤 Ikuo Mito
- 👤 Mitsuhiro Kitamura
- 👤 Kazuhisa Kaede
- 👤 Kohroh Kobayashi
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 19:41
CPC Classifications
H; H01; H01S; H01S5/00; H01S5/20; H01S5/22; H01S5/227; H01S5/40; H01S5/4025; H01S5/4031; H01S5/4043; H10; H10H; H10H20/00; H10H20/01; H10H20/011; H10H20/013; H01S5/2275; H01S5/30; H01S5/32; H01S5/323; H01S5/3235; H01S5/32391
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
236 words
A buried heterostructure laser diode comprising a semiconductor crystal having a pair of principal surfaces and a pair of reflective end surfaces constituting an optical resonator, and a pair of electrodes, said semiconductor crystal including a base semiconductor region having a mesa portion and having a first conductivity type, said mesa portion being elongated and extending between said pair of reflective end surfaces and substantially parallel thereto in a stripe geometry, said semiconductor crystal further including a first semiconductor layer provided only on a top surface of said mesa portion and having a band gap smaller than that of said base semiconductor region and extending between said pair of reflective end surfaces in a stripe geometry, a pair of second semiconductor layers provided on said base region and covering side surfaces of said first layer and side surfaces of said mesa portion and having a second conductivity type and a band gap larger than that of said first layer, a pair of third semiconductor layers provided only on the top surfaces of said second layers and having said first conductivity type and a band gap larger than that of said first layer, and a fourth semiconductor layer commonly provided on the top surfaces of said first layer and said third layers and having said second conductivity type and a band gap larger than that of said first layer, said electrodes being provided on said principal surfaces.
Claim 2
Dependent Claim
236 words
A buried heterostructure laser diode comprising a semiconductor crystal having a pair of principal surfaces and a pair of reflective end surfaces constituting an optical resonator, and a pair of electrodes, said semiconductor crystal including a base semiconductor region having a mesa portion and having a first conductivity type, said mesa portion being elongated and extending between said pair of reflective end surfaces and substantially parallel thereto in a stripe geometry, said semiconductor crystal further including a first semiconductor layer provided only on a top surface of said mesa portion and having a band gap smaller than that of said base semiconductor region and extending between said pair of reflective end surfaces in a stripe geometry, a pair of second semiconductor layers provided on said base region and covering side surfaces of said first layer and side surfaces of said mesa portion and having a second conductivity type and a band gap larger than that of said first layer, a pair of third semiconductor layers provided only on the top surfaces of said second layers and having said first conductivity type and a band gap larger than that of said first layer, and a fourth semiconductor layer commonly provided on the top surfaces of said first layer and said third layers and having said second conductivity type and a band gap larger than that of said first layer, said electrodes being provided on said principal surfaces.
Claim 3
Dependent Claim
25 words
A buried heterostructure laser diode as claimed in claim 1, in which said first layer includes a plurality of semiconductor layers having different band gaps.
Claim 4
Dependent Claim
43 words
A buried heterostructure laser diode as claimed in claim 1, in which said first layer has a width in a range of 2˜2.5 μm and the combined height of the mesa portion and said first layer is in the range of 1.3-2 μm.
Claim 5
Dependent Claim
24 words
A buried heterostructure laser diode as claimed in claim 2 wherein said plurality of semiconductor layers comprises an active layer and a waveguide layer.
Claim 6
Dependent Claim
34 words
A buried heterostructure laser diode as claimed in claim 1 wherein said first semiconductor layer is an active layer, said second semiconductor layers are current-blocking layers, and said third semiconductor layers are current-confining layers.
Claim 7
Dependent Claim
17 words
A buried heterostructure laser diode as claimed in claim 1 wherein said first semiconductor layer comprises InGaAsP.
Claim 8
Dependent Claim
261 words
A multi-wavelength integrated buried heterostructure laser diode device comprising a plurality of laser diodes, said laser diodes being isolated from each other and lasing at different wavelengths, each laser diode comprising a semiconductor crystal having a pair of principal surfaces and a pair of reflective end surfaces constituting an optical resonator, and a pair of electrodes, said semiconductor crystal including a base semiconductor region having a mesa portion and having a first conductivity type, said mesa portion being elongated and extending between said pair of reflective end surfaces and substantially parallel thereto in a stripe geometry, said semiconductor crystal further including a first semiconductor layer provided only on a top surface of said mesa portion and having a band gap smaller than that of said base semiconductor region and extending between said pair of reflective end surfaces in a stripe geometry, a pair of second semiconductor layers provided on said base region and covering side surfaces of said first layer and side surfaces of said mesa portion and having a second conductivity type and a band gap larger than that of said first layer, a pair of third semiconductor layers provided only on the top surfaces of said second layers and having said first conductivity type and a band gap larger than that of said first layer, and a fourth semiconductor layer commonly provided on the top surfaces of said first layer and said third layers and having said second conductivity type and a band tap larger than that of said first layer, said electrodes being provided on said principal surfaces.
Claim 9
Dependent Claim
261 words
A multi-wavelength integrated buried heterostructure laser diode device comprising a plurality of laser diodes, said laser diodes being isolated from each other and lasing at different wavelengths, each laser diode comprising a semiconductor crystal having a pair of principal surfaces and a pair of reflective end surfaces constituting an optical resonator, and a pair of electrodes, said semiconductor crystal including a base semiconductor region having a mesa portion and having a first conductivity type, said mesa portion being elongated and extending between said pair of reflective end surfaces and substantially parallel thereto in a stripe geometry, said semiconductor crystal further including a first semiconductor layer provided only on a top surface of said mesa portion and having a band gap smaller than that of said base semiconductor region and extending between said pair of reflective end surfaces in a stripe geometry, a pair of second semiconductor layers provided on said base region and covering side surfaces of said first layer and side surfaces of said mesa portion and having a second conductivity type and a band gap larger than that of said first layer, a pair of third semiconductor layers provided only on the top surfaces of said second layers and having said first conductivity type and a band gap larger than that of said first layer, and a fourth semiconductor layer commonly provided on the top surfaces of said first layer and said third layers and having said second conductivity type and a band tap larger than that of said first layer, said electrodes being provided on said principal surfaces.
References Cited (Backward Citations)
US4230997A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1987-01-09 | 1987-07-11 | 1988-01-10 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1991-01-09 | 1991-07-11 | 1992-01-10 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1995-01-09 | 1995-07-11 | 1996-01-10 | $7700.00 | Window Closed / Lapsed |