Granted Patent B2

US 12,633,725 · App. 17/761,188 · Granted May 19, 2026

Inventors: Zhigang Chen (Portland, OR); Manoj Kanskar (Portland, OR)

Assignee: nLIGHT, Inc.

H01S5/2031H01S5/3218H01S5/3403

Abstract

Claims (23)

1 . A laser diode, comprising:

a semiconductor substrate having a material composition with a first lattice constant; and

a plurality of epitaxy layers formed on the semiconductor substrate, the plurality of epitaxy layers including a waveguide layer and cladding layers, wherein the waveguide layer includes an active region having a material composition associated with a target optical wavelength, wherein a second lattice constant of the material composition of the active region is different than the first lattice constant, and wherein the cladding layers consist essentially of Al, Ga, As, and P;

wherein a material composition of an individual one of the cladding layers imparts a stress field on the active region;

wherein the individual one of the cladding layers includes a strain adjusting material, and

wherein the individual one of the cladding layers includes two or more sublayers in which an average concentration of the strain adjusting material in one of the sublayers is different than an average concentration of the strain adjusting material in a different one of the sublayers.

2 . The laser diode of claim 1 , wherein the individual one of the cladding layers comprises two or more sublayers having two or more uniform material compositions, respectively.

3 . The laser diode of claim 2 , wherein a first sublayer of the two or more sublayers is closer to the active region than a second sublayer of the two or more sublayers, wherein a degree of lattice mismatch to the first lattice constant in the first sublayer is different than a degree of lattice mismatch to the first lattice constant in the second sublayer.

4 . The laser diode of claim 1 , wherein the individual one of the cladding layers comprises alternating layers having different degrees of lattice mismatch to the first lattice constant.

5 . The laser diode of claim 1 , wherein the individual one of the cladding layers comprises a gradient material composition and a gradient lattice constant.

6 . The laser diode of claim 1 , wherein the strain adjusting material comprises a periodic table Group III material or periodic table Group V material.

7 . The laser diode of claim 1 , wherein the material composition of the individual one of the cladding layers comprises any periodic table group III-V ternary alloy, quaternary alloy, or quinternary alloy.

8 . The laser diode of claim 1 , wherein the individual one of the cladding layers comprises a p-cladding of the cladding layers.

9 . The laser diode of claim 1 , wherein the cladding layers comprise a p-cladding and an n-cladding.

10 . The laser diode of claim 9 , wherein the strain adjusting material is located in the p-cladding.

11 . The laser diode of claim 9 , wherein the strain adjusting material is located in the n-cladding.

12 . The laser diode of claim 9 , wherein cladding layers further comprise a p-cap for the p-cladding.

13 . The laser diode of claim 9 , wherein the n-cladding comprises an inner n-cladding and an outer n-cladding.

14 . The laser diode of claim 1 , wherein the semiconductor substrate comprises an n-substrate.

15 . The laser diode of claim 14 , wherein the n-substrate comprises a GaAs n-substrate.

16 . The laser diode of claim 1 , further comprising a large optical cavity (LOC).

17 . The laser diode of claim 1 , wherein the waveguide layer further includes an n-waveguide and a p-waveguide, wherein a thickness of the p-waveguide is less than 30% of a thickness of the n-waveguide.

18 . The laser diode of claim 1 , wherein the laser diode generates laser light with a wavelength of 900 nm or greater.

Assignments (2)

Continuity (2)

References Cited (24)