Lasers with beam-shape modification

Patent metadata

Field	Value
Publication number	US-9859687-B2
Application number	US-201615160888-A
Country	US
Kind code	B2
Filing date	May 20, 2016
Priority date	May 8, 2012
Publication date	Jan 2, 2018
Grant date	Jan 2, 2018

Abstract

A beam control structure for semiconductor lasers that allows modification of the shape of a beam allowing, for example, higher coupling into an optical fiber. The structure may comprise one or more of a tilted patio, a staircase, a reflective roof, and a reflective sidewall.

First claim

The invention claimed is:

1. A method for forming a semiconductor chip, comprising:
providing a substrate having a substrate surface;
forming an epitaxial laser on the substrate surface; and
etching the epitaxial laser to form an etched facet on said epitaxial laser;
wherein said substrate extends outwardly from said etched facet to form a patio comprising an exposed reflective surface and a plurality of steps formed therein, wherein said plurality of steps comprises a first step having a step surface abutting said etched facet, wherein said plurality of steps further comprises one or more subsequent steps each having a step surface substantially parallel with said substrate surface; wherein each subsequent step outwardly from said etched facet extends further into said substrate such that light emitted from said epitaxial laser is reflected off said exposed reflective surface of at least one of said plurality of steps to modify a vertical far field of said epitaxial laser.

2. The method of claim 1 , further comprising forming at least one reflective sidewall extending outwardly from said etched facet.

3. The method of claim 1 , further comprising forming a reflective roof disposed opposite from said patio extending outwardly from said etched facet.

4. The method of claim 1 , further comprising forming a reflective coating deposited on said patio.

5. The method of claim 1 , wherein said substrate is selected from the group comprising InP, GaAs, and GaN.

6. A method for forming a semiconductor chip, comprising:
providing a substrate having a substrate surface;
forming an epitaxial laser on said substrate;
etching the epitaxial laser to form an etched facet on said epitaxial laser; and
forming a patio in said substrate extending outwardly from said etched facet, said patio having an exposed reflective surface and a plurality of steps formed therein, wherein said plurality of steps comprises a first step having a step surface abutting said etched facet, wherein said plurality of steps further comprises one or more subsequent steps each having a step surface substantially parallel with said substrate surface; wherein each subsequent step outwardly from said etched facet extends further into said substrate such that light emitted from said epitaxial laser is reflected off of said exposed reflective surface of at least one of said plurality of steps to modify a vertical far field of said epitaxial laser.

7. The method of claim 6 , further comprising forming at least one reflective sidewall extending outwardly from said etched facet.

8. The method of claim 6 , wherein said substrate is selected from the group comprising InP, GaAs, and GaN.

9. A method for forming a semiconductor chip, comprising:
providing a substrate;
forming an epitaxial laser on a surface of said substrate;
etching the epitaxial laser to form an etched facet on said epitaxial laser, said etched facet having an angle other than 90° to said surface of said substrate; and
forming a structure adjacent said etched facet, said structure having at least two opposing reflective surfaces extending outwardly from said etched facet, wherein said at least two opposing reflective surfaces are positioned relative to said etched facet such that light emitted from said epitaxial laser is reflected off of said at least two opposing reflective surfaces to modify a vertical far field of said epitaxial laser.

10. The method of claim 9 , wherein said structure is titled patio.

11. The method of claim 10 , wherein said at least two opposing reflective surfaces comprises at least two reflective sidewalls.

12. The method of claim 11 , wherein each sidewall is separated from said etched facet with a gap.

13. The method of claim 9 , wherein said structure further comprises a staircase containing a plurality of steps having reflective surfaces.

14. The method of claim 13 , wherein said at least two opposing reflective surfaces comprises at least two reflective sidewalls.

15. The method of claim 14 , wherein each sidewall is separated from said etched facet with a gap.

16. The method of claim 9 , wherein said substrate is selected from the group comprising InP, GaAs, and GaN.

17. A method for forming a hybrid assembly, comprising:
forming a base with an exposed reflective surface of a patio having a downwards staircase with a plurality of steps, wherein said plurality of steps comprises a first step having a step surface and one or more subsequent steps each having a step surface; wherein said first step extends into said base from a top surface of said base and each subsequent step extends further into said base; and
mounting a laser with an active layer and at least one cleaved facet on said top surface of said base;
wherein said at least one cleaved facet is positioned adjacent to said exposed reflective surface of said first step such that light emitted from said laser is reflected off of said exposed reflective surface of said plurality of steps to modify a vertical far field of said laser.

18. The method of claim 17 , further comprising forming a reflective structure adjacent said cleaved facet.

19. The method of claim 17 , wherein said laser is formed from a laser structure epitaxially deposited on a substrate selected from the group comprising InP, GaAs, and GaN.

20. The method of claim 17 , wherein said base further includes a stopper against which said laser is positioned on said base.

Assignees

• Macom Tech Solutions Holdings Inc

Inventors

• Stagarescu Cristian
• Behfar Alex A
• Kwong Norman Sze-Keung

Classifications

• H01S2301/18

  Semiconductor lasers with special structural design for influencing the near- or far-field · CPC title

• B82Y20/00

  Nanooptics, e.g. quantum optics or photonic crystals · CPC title

• H01S5/1085

  Oblique facets · CPC title

• H01S5/3013 Primary

  AIIIBV compounds · CPC title

• H01S5/22

  having a ridge or stripe structure · CPC title