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US5212702A Expired / Lapsed US ⏱️ 0.0 years remaining

Semiconductor surface emitting laser having reduced threshold voltage and enhanced optical output

Assignee: Nokia Bell Labs
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Filing: 1992-03-25
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Granted: 1993-05-18
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Expires: 2012-03-25
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Abstract

Abstract The present applicant has discovered that one can make a surface emitting laser with enhanced operating characteristics by etching away the outer reflector stack peripheral to the intended active area and protecting the reflector stack mesa remaining over the active area by in situ metalization in high vacuum. The active area can be isolated, as by ion implantation, providing an electrical path through the active region free of the outer reflector stack. The result is a surface emitting laser having reduced series resistance. The device lases at lower voltage and provides an enhanced intensity of optical output as compared with conventional planar devices.

Inventors

  • 👤 Kent D. Choquette

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-30 16:26
CPC Classifications
H; H01; H01S; H01S5/00; H01S5/10; H01S5/18; H01S5/183; H01S5/18308; H01S5/04; H01S5/042; H01S5/0421; H01S5/20; H01S5/2054; H01S5/2059; H01S5/2063; Y; Y10; Y10S; Y10S438/00; Y10S438/913

Claims Analysis

Total Claims: 6
Claim 1
Independent Claim 81 words
In a vertical cavity, surface emitting laser of the type comprising a semiconductor active region disposed between a pair of Bragg reflector stacks each comprising a plurality of longitudinally extending reflector layers and a pair of metal contact layers for providing a current through said active region, the improvement wherein at least one of said reflector stacks terminates in at least one substantially transverse wall peripheral to said active region and one of said metal contact layers substantially covers said wall.
Claim 2
Dependent Claim 81 words
In a vertical cavity, surface emitting laser of the type comprising a semiconductor active region disposed between a pair of Bragg reflector stacks each comprising a plurality of longitudinally extending reflector layers and a pair of metal contact layers for providing a current through said active region, the improvement wherein at least one of said reflector stacks terminates in at least one substantially transverse wall peripheral to said active region and one of said metal contact layers substantially covers said wall.
Claim 3
Dependent Claim 24 words
The improved device of claim 1 wherein said at least one reflector stack terminates within 10 micrometers of the periphery of said active region.
Claim 4
Dependent Claim 31 words
The improved device of claim 1 wherein said at least one reflector stack has a longitudinally extending outer layer and a layer of silicon dioxide is disposed on said outer layer.
Claim 5
Dependent Claim 36 words
The improved laser of claim 1 wherein said active region comprises a quantum well region disposed between a pair of confinement layers and said metal contact layer covering said wall contacts one of said confinement layers.
Claim 6
Dependent Claim 29 words
The improved laser of claim 1 wherein said reflector stacks comprise aluminum gallium arsenide, said active region comprises gallium arsenide, and said metal layer covering said wall comprises gold.

References Cited (Backward Citations)

US5018159A Cited
JPH0321090A Cited
JPH0321091A 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

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