US5212703A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Surface emitting lasers with low resistance bragg reflectors
Assignee: Eastman Kodak Co
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Filing: 1992-02-18
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Granted: 1993-05-18
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Expires: 2012-02-18
Abstract
Abstract A vertical cavity surface emitting laser is disclosed including a lower cladding layer of a particular conductivity type deposited on the semiconductor substrate, having multiple periods of semiconductor layers of varying index cf refraction so deposited as to form a λ/2 Bragg reflector; and an upper cladding layer of opposite conductivity type having multiple periods of semiconductor layers of varying index of refraction so deposited as to form a multilayer reflector.
Inventors
- 👤 Keith B. Kahen
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 02:53
CPC Classifications
H; H01; H01S; H01S5/00; H01S5/10; H01S5/18; H01S5/183; H01S5/18361; H01S5/18305; H01S5/30; H01S5/32; H01S5/3211
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
113 words
A vertical cavity surface emitting laser, comprising: (a) a semiconductor substrate of one conductivity type; (b) a lower cladding layer of similar conductivity type deposited on the semiconductor substrate, having multiple periods of semiconductor layers of varying index of refraction so deposited as to form a λ/2 Bragg reflector; (c) a semiconductor active layer formed on the lower cladding layer; (d) an upper cladding layer of opposite conductivity type deposited on the semiconductor active layer, having multiple periods of semiconductor layers of varying index of refraction so deposited as to form a multilayer reflector; (e) deposited on the upper cladding layer; and (f) electrically conductive layers, deposited on the substrate and cap layers.
Claim 2
Dependent Claim
113 words
A vertical cavity surface emitting laser, comprising: (a) a semiconductor substrate of one conductivity type; (b) a lower cladding layer of similar conductivity type deposited on the semiconductor substrate, having multiple periods of semiconductor layers of varying index of refraction so deposited as to form a λ/2 Bragg reflector; (c) a semiconductor active layer formed on the lower cladding layer; (d) an upper cladding layer of opposite conductivity type deposited on the semiconductor active layer, having multiple periods of semiconductor layers of varying index of refraction so deposited as to form a multilayer reflector; (e) deposited on the upper cladding layer; and (f) electrically conductive layers, deposited on the substrate and cap layers.
Claim 3
Dependent Claim
21 words
The vertical cavity surface emitting laser of claim 1 in which the conductivity of the substrate is either n- or p-type.
Claim 4
Dependent Claim
28 words
The vertical cavity surface emitting laser of claim 1 in which the substrate is composed of GaAs, the cladding layers of AlGaAs, and the active layer of InGaAs.
Claim 5
Dependent Claim
22 words
The vertical cavity surface emitting laser of claim 1 in which the active layer comprises either a single or multiple quantum wells
Claim 6
Dependent Claim
30 words
The vertical cavity surface emitting laser of claim 1 in which the multilayer reflector formed in the upper cladding layer is either a λ/4 reflector or a λ/2 Bragg reflector.
Claim 7
Dependent Claim
30 words
The vertical cavity surface emitting laser of claim 1 in which a GRINSCH structure surrounds the active layer so as to maximize the optical confinement factor and minority carrier capture.
Claim 8
Dependent Claim
30 words
The vertical cavity surface emitting laser of claim 1 in which the semiconductor interfaces of the multilayer reflectors are compositionally graded so as to achieve lower resistance to current flow.
Claim 9
Dependent Claim
31 words
The vertical cavity surface emitting laser of claim 1 in which the substrate side conductive material is patterned so as to enable light output through the bottom surface of the laser.
References Cited (Backward Citations)
US5115441A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1996-05-17 | 1996-11-16 | 1997-05-18 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2000-05-17 | 2000-11-16 | 2001-05-18 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2004-05-17 | 2004-11-16 | 2005-05-18 | $7700.00 | Window Closed / Lapsed |