METHOD OF MANUFACTURING SURFACE EMITTING LASER

• US 20200136352A1
• Filed: 09/20/2019
• Published: 04/30/2020
• Est. Priority Date: 10/25/2018
• Status: Active Grant

• Current Assignee: Sumitomo Electric Industries Limited (Sumitomo Corporation)
• Original Assignee: Sumitomo Electric Industries Limited (Sumitomo Corporation)
• Inventors: TSUJI, Yukihiro
• Granted Patent: US 10,916,917 B2
• Time in Patent Office: Days
• CPC Class Codes: H01S 2301/176 Specific passivation layers on surfaces other than the emission facet
• CPC Class Codes: H01S 2304/00 Special growth methods for semiconductor lasers
• CPC Class Codes: H01S 5/0206 Substrates, e.g. growth, shape, material, removal or bonding; specific crystal orientation H01S5/3202
• CPC Class Codes: H01S 5/04252 characterised by the material
• CPC Class Codes: H01S 5/18308 having a special structure for lateral current or light confinement
• CPC Class Codes: H01S 5/18313 by oxidizing at least one of the DBR layers
• CPC Class Codes: H01S 5/18347 Mesa comprising active layer
• CPC Class Codes: H01S 5/18361 Structure of the reflectors, e.g. hybrid mirrors
• CPC Class Codes: H01S 5/2063 obtained by particle bombardment
• CPC Class Codes: H01S 5/34313 with a well layer having only As as V-compound, e.g. AlGaAs, InGaAs

Abstract

A method of manufacturing a surface emitting laser includes: forming a mesa by performing etching on a lower reflector layer, an active layer, and an upper reflector layer; forming a current narrowing layer by oxidizing a part of the upper reflector layer; exposing a substrate by performing etching on the lower reflector layer, the active layer, and the upper reflector layer, using a chlorine-containing gas; cleaning the substrate; performing heat treatment on the substrate; forming an insulating film covering a surface of the substrate; forming an electrode on the lower reflector layer and the upper reflector layer; and performing heat treatment on the substrate, wherein a temperature in the first heat treatment is lower than a temperature in the forming the current narrowing layer.

Claims

1. A method of manufacturing a surface emitting laser,

the method comprising:

a step of preparing a substrate containing gallium and arsenic, a lower reflector layer, an active layer, and an upper reflector layer being formed sequentially in the substrate, the lower reflector layer including a semiconductor multilayer film, the upper reflector layer including a semiconductor multilayer film;

a step of forming a mesa by performing etching on the lower reflector layer, the active layer, and the upper reflector layer;

a step of forming a current narrowing layer by oxidizing a part of the upper reflector layer, after the step of forming the mesa;

a step of exposing the substrate by performing etching on the lower reflector layer, the active layer, and the upper reflector layer, using a chlorine-containing gas;

a step of cleaning the substrate, after the step of exposing the substrate;

a first heat treatment step of performing heat treatment on the substrate, after the step of cleaning;

a step of forming an insulating film covering a surface of the substrate exposed by the etching, after the first heat treatment step;

a step of forming an electrode on the lower reflector layer and the upper reflector layer; and

a second heat treatment step of performing heat treatment on the substrate after the formation of the electrode,

wherein a temperature in the first heat treatment step is lower than a temperature in the step of forming the current narrowing layer.

2. The method according to claim 1, wherein the temperature in the first heat treatment step is not lower than 250 degrees C. and not higher than 350 degrees C.

3. The method according to claim 1, wherein the substrate is disposed in a reduced-pressure atmosphere in the first heat treatment step.

4. The method according to claim 1, wherein the first heat treatment step is continued for not shorter than 30 minutes and not longer than one hour.