Surface-emitting semiconductor laser, method for producing the same, surface-emitting semiconductor laser device, optical transmission device, and information processing device

Patent metadata

Field	Value
Publication number	US-10033157-B2
Application number	US-201514810601-A
Country	US
Kind code	B2
Filing date	Jul 28, 2015
Priority date	Aug 26, 2014
Publication date	Jul 24, 2018
Grant date	Jul 24, 2018

Abstract

A surface-emitting semiconductor laser includes a first semiconductor multilayer film reflector, an active region, a second semiconductor multilayer film reflector, and a current confinement layer including an oxidized region formed by selective oxidation. The current confinement layer includes a first semiconductor layer having a relatively high Al content, a second semiconductor layer that is adjacent to the first semiconductor layer on an active-region side of the first semiconductor layer and has a lower Al content than the first semiconductor layer, and a composition-gradient layer adjacent to the first semiconductor layer on a side of the first semiconductor layer which is opposite to the active-region side. A portion of the composition-gradient layer which faces the first semiconductor layer has a lower Al content than the first semiconductor layer.

First claim

What is claimed is:

1. A surface-emitting semiconductor laser comprising:
a first semiconductor multilayer film reflector;
an active region;
a second semiconductor multilayer film reflector; and
a current confinement layer including an oxidized region formed by selective oxidation,
wherein the current confinement layer includes
a first semiconductor layer having a relatively high Al content,
a second semiconductor layer adjacent to the first semiconductor layer, the second semiconductor layer being disposed on an active-region side of the first semiconductor layer, the second semiconductor layer having a lower Al content than the first semiconductor layer, and
a composition-gradient layer adjacent to the first semiconductor layer, the composition-gradient layer being disposed on a side of the first semiconductor layer which is opposite to the active-region side on which the second semiconductor layer is disposed, and

wherein a portion of the composition-gradient layer which faces the first semiconductor layer has a lower Al content than the first semiconductor layer such that there is a discontinuity between the Al content in the first semiconductor layer and a maximum Al content in the composition-gradient layer in the portion of the composition-gradient layer.

2. The surface-emitting semiconductor laser according to claim 1 ,
wherein a difference in Al content between the portion of the composition-gradient layer which faces the first semiconductor layer and the first semiconductor layer is made such that an oxidation rate in the composition-gradient layer is lower than an oxidation rate in the first semiconductor layer by about one order of magnitude.

3. The surface-emitting semiconductor laser according to claim 1 ,
wherein the portion of the composition-gradient layer which faces the first semiconductor layer has an Al content of about 0.90 or less.

4. The surface-emitting semiconductor laser according to claim 1 ,
wherein the second semiconductor layer is adjacent to the active region.

5. The surface-emitting semiconductor laser according to claim 1 ,
wherein the composition-gradient layer is adjacent to a high-refractive-index layer constituting the second semiconductor multilayer film reflector, and
wherein an Al content in the composition-gradient layer is reduced to an Al content substantially equal to an Al content in the high-refractive-index layer.

6. The surface-emitting semiconductor laser according to claim 1 ,
wherein the first semiconductor layer is composed of AlAs.

7. The surface-emitting semiconductor laser according to claim 1 ,
wherein the first semiconductor layer has a thickness of about 10 nm or more to about 50 nm or less.

8. A surface-emitting semiconductor laser device comprising:
the surface-emitting semiconductor laser according to claim 1 ; and
an optical element that light emitted by the surface-emitting semiconductor laser enters.

9. An optical transmission device comprising:
the surface-emitting semiconductor laser device according to claim 8 ; and
a transmission unit that transmits a laser beam emitted by the surface-emitting semiconductor laser device via an optical medium.

10. An information processing device comprising:
the surface-emitting semiconductor laser according to claim 1 ;
a light-condensing unit that condenses a laser beam emitted by the surface-emitting semiconductor laser on a recording medium; and
a mechanism that scans the recording medium with the laser beam condensed by the light-condensing unit.

Assignees

• Fuji Xerox Co Ltd

Inventors

• Takeda Kazutaka
• Hayakawa Junichiro
• Murakami Akemi
• Jogan Naoki
• Kondo Takashi
• Sakurai Jun

Classifications

• H01S5/18361

  Structure of the reflectors, e.g. hybrid mirrors · CPC title

• H01S5/18394

  Apertures, e.g. defined by the shape of the upper electrode · CPC title

• H01S5/18313

  by oxidizing at least one of the DBR layers · CPC title

• H01S5/3432

  the whole junction comprising only (AI)GaAs · CPC title

• H01S5/18347

  Mesa comprising active layer · CPC title