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US5212706A Expired / Lapsed US ⏱️ 0.0 years remaining

Laser diode assembly with tunnel junctions and providing multiple beams

Assignee: University of Connecticut
•
Filing: 1991-12-03
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Granted: 1993-05-18
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Expires: 2011-12-03
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Abstract

Abstract A laser diode assembly provides multiple output beams from multiple p-n junctions in a multiplicity of stacked laser diodes with at least one tunnel junction. A semiconductor substrate has a multiplicity of superposed semiconductor laser stacks thereon each having an active layer sandwiched between p and n layers, and at least one pair of adjacent semiconductor laser stacks has a tunnel junction therebetween. When a potential is applied across the ohmic contacts on the outer surface of the substrate and the outer surface of the uppermost semiconductor laser stack, lasing is produced in the semiconductor stacks to form multiple beams. The tunnel junction may be provided by highly doped p + , n + layers between the stacks, or it may be provided by highly doped abutting p + , n + surface portions in the adjacent stacks. Tunnel junctions may be provided at the interfaces between all of the stacks, or between all but one pair of the adjacent stacks. The assembly may be edge emitting or surface emitting, and it may include single or multiple quantum well configurations and distributed feedback configuration.

Inventors

  • 👤 Faquir C. Jain

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-28 12:46
CPC Classifications
H; H01; H01S; H01S5/00; H01S5/40; H01S5/4025; H01S5/4031; H01S5/4043; B; B82; B82Y; B82Y20/00; H01S2301/00; H01S2301/17; H01S2301/176; H01S5/10; H01S5/18; H01S5/183; H01S5/18305; H01S5/18397; H01S5/20; H01S5/22; H01S5/223; H01S5/30; H01S5/305; H01S5/3095; H01S5/34; H01S5/343; H01S5/34313; H01S5/3432; H01S5/4018; H01S5/4087

Claims Analysis

Total Claims: 16
Claim 1
Independent Claim 104 words
A laser diode assembly providing multiple output beams from multiple p-n junctions and at least one tunnel junction comprising: (a) a semiconductor substrate; (b) a multiplicity of superposed semiconductor laser stacks thereon each having an active layer sandwiched between p and n layers, and at least one pair of adjacent semiconductor laser stacks having a tunnel junction therebetween; and (c) ohmic contacts on the outer surface of said substrate and the outer surface of the uppermost semiconductor laser stack, whereby an applied potential across said ohmic contacts produces lasing in the active layers semiconductor laser stacks on the opposite sides of said tunnel junction.
Claim 2
Dependent Claim 104 words
A laser diode assembly providing multiple output beams from multiple p-n junctions and at least one tunnel junction comprising: (a) a semiconductor substrate; (b) a multiplicity of superposed semiconductor laser stacks thereon each having an active layer sandwiched between p and n layers, and at least one pair of adjacent semiconductor laser stacks having a tunnel junction therebetween; and (c) ohmic contacts on the outer surface of said substrate and the outer surface of the uppermost semiconductor laser stack, whereby an applied potential across said ohmic contacts produces lasing in the active layers semiconductor laser stacks on the opposite sides of said tunnel junction.
Claim 3
Dependent Claim 34 words
The laser diode assembly in accordance with claim 1 wherein the ends of said semiconductor stacks are reflecting and form a cavity, and wherein laser beams are emitted through one end of said stacks.
Claim 4
Dependent Claim 27 words
The laser diode assembly in accordance with claim 1 wherein said tunnel junction is provided by highly doped p + , n + layers between said stacks.
Claim 5
Dependent Claim 39 words
The laser diode assembly in accordance with claim 3 wherein an assembly of adjacent stacks and tunnel junction comprises, seriatim, p, n, n + , p + p, n, n + , p + , p and n layers.
Claim 6
Dependent Claim 30 words
The laser diode assembly in accordance with claim 1 wherein said tunnel junction is provided by highly doped abutting p + , n + surface portions in the adjacent stacks.
Claim 7
Dependent Claim 38 words
The laser diode assembly in accordance with claim 1 wherein the top and bottom stacks are dimensioned and formulated to provide reflecting dielectric mirrors at the top and bottom of the assembly and thereby confine the lasing therebetween.
Claim 8
Dependent Claim 28 words
The laser diode assembly in accordance with claim 6 wherein said substrate permits the laser beam to exit from the bottom dielectric mirror of the laser diode assembly.
Claim 9
Dependent Claim 29 words
The laser diode assembly in accordance with claim 6 wherein said dielectric mirrors are realized by quarter wave thick layers of compatible low and high index of refraction semiconductors.
Claim 10
Dependent Claim 28 words
The laser diode assembly in accordance with claim 7 wherein said substrate and its ohmic contact are configured to provide an aperture for the laser beam to exit.
Claim 11
Dependent Claim 38 words
The laser diode assembly in accordance with claim 7 wherein the dimensions and composition of the semiconductor layers of said stacks and substrate cooperate to generate a laser beam of a wavelength to which the substrate is transparent.
Claim 12
Dependent Claim 27 words
The laser diode assembly in accordance with claim 1 wherein at least one of said laser stacks has an active layer which provides a multiple quantum well.
Claim 13
Dependent Claim 44 words
The laser diode assembly in accordance with claim 1 wherein positive distributed feedback is provided by periodic corrugation on at least one side of the active layer of at least one stack and the laser beams are emitted through one end of the assembly.
Claim 14
Dependent Claim 30 words
The laser diode assembly in accordance with claim 1 wherein at least two of said stacks are of different composition to provide laser beams of at least two different wavelengths.
Claim 15
Dependent Claim 19 words
The laser diode assembly in accordance with claim 1 wherein tunnel junctions are provided between all of said stacks.
Claim 16
Dependent Claim 41 words
The laser diode assembly in accordance with claim 1 wherein tunnel junctions are provided between all but one pair of said adjacent stacks to provide, seriatim, p,n,p,n layers in said but one pair, to exhibit optoelectronic triggering inherent in p-n,p-n structures.

References Cited (Backward Citations)

US4577207A Cited
JPH0229487A 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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