Edge-emitting etched-facet lasers

Patent metadata

Field	Value
Publication number	US-2018090907-A1
Application number	US-201715829133-A
Country	US
Kind code	A1
Filing date	Dec 1, 2017
Priority date	Dec 8, 2011
Publication date	Mar 29, 2018
Grant date	—

Abstract

A laser chip having a substrate, an epitaxial structure on the substrate, the epitaxial structure including an active region and the active region generating light, a waveguide formed in the epitaxial structure extending in a first direction, the waveguide having a front etched facet and a back etched facet that define an edge-emitting laser, and a first recessed region formed in the epitaxial structure, the first recessed region being arranged at a distance from the waveguide and having an opening adjacent to the back etched facet, the first recessed region facilitating testing of an adjacent laser chip prior to singulation of the laser chip.

First claim

1 . A method of fabricating a semiconductor laser structure comprising:
epitaxially depositing a structure on a substrate, the structure including an active region for generating light; forming first and second waveguides in first and second portions of the structure, respectively, the first waveguide having a first front etched fact and a first back etched facet, the second waveguide having a second front etched fact and a second back etched facet; forming a recessed region in the first portion of the structure, the recessed region having an opening directly opposing the second front etched facet of the second waveguide, the recessed region facilitating testing of the second waveguide prior to singulation of the second portion of the structure from the substrate.

2 . The method of claim 1 , wherein the recessed region comprises an end wall upon which light from the second front etched facet of the second waveguide impinges.

3 . The method of claim 2 , wherein the first waveguide extends in a first direction, wherein the end wall is at an angle other than normal to the first direction to reflect light from the second front etched facet impinging upon the end wall.

4 . The method of claim 1 , further comprising coating at least one of the first back etched facet and the second back etched facet with a highly reflective material.

5 . The method of claim 1 , wherein the first front etched fact and the first back etched facet of the first waveguide define a first edge-emitting laser.

6 . The method of claim 5 , wherein the edge-emitting laser is a ridge laser.

7 . The method of claim 6 , wherein the ridge laser is of a Fabry-Perot (FP) type.

8 . The method of claim 6 , wherein the ridge laser is of a distributed feedback (DFB) type.

9 . The method of claim 5 , wherein the edge-emitting laser is a Buried Heterostructure (BH) laser.

10 . The method of claim 9 , wherein the BH laser is of a Fabry-Perot (FP) type.

11 . The method of claim 9 , wherein the BH laser is of a distributed feedback (DFB) type.

12 . The method of claim 1 , wherein the recessed region is a first recessed region, further comprising:
forming a second recessed region in the first portion of the structure, the second recessed region having an opening directly opposing a third back etched facet of a third waveguide in a third portion of the structure, the second recessed region facilitating coating of the third back etched facet with a highly reflective material prior to singulation of the third portion of the structure from the substrate.

13 . The method of claim 12 , wherein the opening of the first recessed region and the opening of the second recessed region are aligned to each other in the first portion of the structure.

14 . The method of claim 1 , wherein the recessed region is a first recessed region, further comprising:
forming a second recessed region in the second portion of the structure, the second recessed region having an opening directly opposing a first back etched facet of the first waveguide, the second recessed region facilitating coating of the first back etched facet with a highly reflective material prior to singulation of the second portion of the structure from the substrate.

15 . The method of claim 14 , further comprising:
forming a third recessed region in the second portion of the structure, the third recessed region having an opening directly opposing a third front etched facet of a third waveguide in a third portion of the structure, the third recessed region facilitating testing of the third waveguide prior to singulation of the third portion of the structure from the substrate.

16 . The method of claim 15 , wherein the opening of the second recessed region and the opening of the third recessed region are aligned to each other in the second portion of the structure.

17 . The method of claim 15 , wherein the second waveguide extends in a second direction, wherein the second recessed region comprises a second end wall upon which light from the third front etched facet of the third waveguide impinges.

18 . The method of claim 17 , wherein the second end wall is at an angle other than normal to the second direction to reflect light from the third front etched facet impinging upon the second end wall.

19 . The method of claim 1 , wherein the substrate is formed of one of: InP, GaAs, and GaN.

20 . The method of claim 1 , wherein the first portion of the structure is a common contiguous portion of the structure comprising the recessed region and the first front and back etched facets defining a first edge-emitting laser, wherein the first portion of the structure is spaced apart from and does not include the second portion of the structure.

Assignees

• Macom Tech Solutions Holdings Inc

Inventors

• Behfar Alex A
• Green Malcolm R
• Stagarescu Cristian

Classifications

• H01S5/0203

  Etching · CPC title

• H01S5/0014 Primary

  Measuring characteristics or properties thereof (measuring techniques per se G01J, G01K, G01N, G01R) · CPC title

• H01S5/0201

  Separation of the wafer into individual elements, e.g. by dicing, cleaving, etching or directly during growth · CPC title

• H01S5/223

  Buried stripe structure {(H01S5/227 takes precedence)} · CPC title

• H01S5/22

  having a ridge or stripe structure · CPC title