Semiconductor laser device, semiconductor laser module, and welding laser light source system

Patent metadata

Field	Value
Publication number	US-11437780-B2
Application number	US-201916567336-A
Country	US
Kind code	B2
Filing date	Sep 11, 2019
Priority date	Mar 16, 2017
Publication date	Sep 6, 2022
Grant date	Sep 6, 2022

Abstract

A semiconductor laser device lases in a multiple transverse mode and includes a stacked structure where a first conductivity-side semiconductor layer, an active layer, and a second conductivity-side semiconductor layer are stacked above a substrate. The second conductivity-side semiconductor layer includes a current block layer having an opening that delimits a current injection region. Side faces as a pair are formed in portions of the stacked structure that range from part of the first conductivity-side semiconductor layer to the second conductivity-side semiconductor layer. The active layer has a second width greater than a first width of the opening. The side faces in at least part of the first conductivity-side semiconductor layer are inclined to the substrate. A maximum intensity position in a light distribution of light guided in the stacked structure, in a direction of the normal to the substrate, is within the first conductivity-side semiconductor layer.

First claim

What is claimed is:

1. A semiconductor laser device that lases in a multiple transverse mode, comprising:
a substrate having a main surface; and
a stacked structure including a first conductivity-side semiconductor layer, an active layer, and a second conductivity-side semiconductor layer that are sequentially stacked above the main surface of the substrate,
wherein the second conductivity-side semiconductor layer includes an opening that delimits a current injection region,
a pair of side faces is formed in portions of the stacked structure that range from part of the first conductivity-side semiconductor layer to the second conductivity-side semiconductor layer,
the active layer has a second width greater than a first width of the opening,
the pair of side faces in at least part of the first conductivity-side semiconductor layer is inclined to the main surface of the substrate,
a maximum intensity position in a light distribution of light guided in the stacked structure, in a direction of a normal to the main surface of the substrate, is within the first conductivity-side semiconductor layer,
each of the pair of side faces includes a first side face on a side close to the substrate and a second side face on a side farther away from the substrate,
θ 1 is less than 90 degrees, θ 1 being an angle formed by a direction of a normal to the first side face and the direction of the normal to the main surface of the substrate,
θ 2 is greater than 90 degrees, θ 2 being an angle formed by a direction of a normal to the second side face and the direction of the normal to the main surface of the substrate,
the pair of side faces is covered with a dielectric film, and
the first side face and the second side face are an interface between the dielectric film and the stacked structure.

2. The semiconductor laser device according to claim 1 , wherein θ 2 is greater than or equal to 120° and less than or equal to 150°.

3. The semiconductor laser device according to claim 1 ,
wherein the stacked structure has a narrowest portion in an area ranging from part of the first conductivity-side semiconductor layer to the second conductivity-side semiconductor layer that are sandwiched between the pair of side faces, and
the narrowest portion has a width greater than the first width.

4. The semiconductor laser device according to claim 3 , wherein the narrowest portion is within the second conductivity-side semiconductor layer.

5. The semiconductor laser device according to claim 3 ,
wherein the second conductivity-side semiconductor layer includes a second conductivity-side first semiconductor layer, a second conductivity-side second semiconductor layer, and a second conductivity-side contact layer that are provided on the substrate in an order mentioned,
and
the narrowest portion is at an interface between the second conductivity-side second semiconductor layer and the second conductivity-side contact layer or in the second conductivity-side layer.

6. The semiconductor laser device according to claim 1 ,
wherein the first conductivity-side semiconductor layer includes a first conductivity-side first semiconductor layer and a first conductivity-side second semiconductor layer that are provided on the substrate in an order mentioned, and
the following relation is satisfied:

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Assignees

• Panasonic Ip Man Co Ltd
• Nuvoton Technology Corp Japan

Inventors

• Ikedo Norio
• Nakatani Tougo
• Okaguchi takahiro
• Yokoyama Takeshi
• Yabushita Tomohito
• Takayama Toru

Classifications

• H01S5/2031

  characterized by special waveguide layers, e.g. asymmetric waveguide layers or defined bandgap discontinuities · CPC title

• H01S5/20

  Structure or shape of the semiconductor body to guide the optical wave {; Confining structures perpendicular to the optical axis, e.g. index or gain guiding, stripe geometry, broad area lasers, gain tailoring, transverse or lateral reflectors, special cladding structures, MQW barrier reflection layers} · CPC title

• H01S2301/16

  Semiconductor lasers with special structural design to influence the modes, e.g. specific multimode · CPC title

• H01S5/3213

  asymmetric clading layers · CPC title

• B23K26/703

  Cooling arrangements (by using a fluid stream B23K26/14) · CPC title