# US 11,114,817 B2 · Semiconductor laser device

> Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt

- Number: US 11,114,817 B2
- Document ID: US11114817B2
- Status: Granted
- Kind: B2
- Application number: 15/936,178
- Filed: 2018-03-26
- Published: 2018-09-27
- Granted: 2021-09-07
- Earliest claimed: 2017-03-27
- Assignees: Ushio Denki Kabushiki Kaisha
- Applicants: Ushio Denki Kabushiki Kaisha
- Inventors: Masato Hagimoto; Hironori Yanagisawa; Tomonobu Tsuchiya
- Web page: https://patentgrep.com/patent/US11114817B2

## CPC

- H01S 5/02476: {Heat spreaders, i.e. improving heat flow between laser chip and heat dissipating elements}
- H01S 5/0237: by soldering
- H01S 5/02469: {Passive cooling, e.g. where heat is removed by the housing as a whole or by a heat pipe without any active cooling element like a TEC}
- H01S 5/02212: Can-type, e.g. TO-CAN housings with emission along or parallel to symmetry axis
- H01S: DEVICES USING THE PROCESS OF LIGHT AMPLIFICATION BY STIMULATED EMISSION OF RADIATION [LASER] TO AMPLIFY OR GENERATE LIGHT; DEVICES USING STIMULATED EMISSION OF ELECTROMAGNETIC RADIATION IN WAVE RANGES OTHER THAN OPTICAL

## Abstract

Disclosed herein is a semiconductor laser device utilizing a sub-mount substrate that is capable of having a further sufficient heat dissipation property. The semiconductor laser device comprises: a monocrystalline sub-mount substrate having a crystalline structure including a first crystalline plane (c-plane) having a normal line direction on a first crystalline axis (c-axis) and a second crystalline plane (a-plane) having a normal line direction on a second crystalline axis (a-axis) having a higher thermal conductivity than the first crystalline axis; and a semiconductor laser chip configured to be joined to a side of a first surface of the sub-mount substrate. The first crystalline plane inclines with respect to the first surface of the sub-mount substrate.

## Claims

### Claim 1

A semiconductor laser device, comprising:
a monocrystalline electrically conductive GaN sub-mount substrate having a crystalline structure including a first crystalline plane and a second crystalline plane, the first crystalline plane being a c-plane and having a normal line direction thereof on a first crystalline axis and the second crystalline plane being an a-plane and having a normal line direction thereof on a second crystalline axis having a higher thermal conductivity than the first crystalline axis;
a semiconductor laser chip configured to be joined to a side of a first surface of the sub-mount substrate;
a first joining layer configured to join the semiconductor laser chip to the first surface of the sub-mount substrate;
a second joining layer configured to join a second surface of the sub-mount substrate to a heatsink; and
an insulating film having a thickness less than 10 um and greater than or equal to 0.2 um and configured to insulate the semiconductor laser chip from the heatsink, and
the first surface of the sub-mount substrate being offset from the first crystalline plane at an angle between 4 degrees and 20 degrees so as to add a component in a direction of the second crystalline axis which has a higher thermal conductivity as compared to a line normal to the first surface of the sub-mount substrate.

### Claim 2 (depends on 1)

The semiconductor laser device according to claim 1,
wherein
a normal line direction of the first surface and a normal line direction of the second surface coincide with each other.

### Claim 3 (depends on 1)

The semiconductor laser device according to claim 1,
wherein the semiconductor laser chip has a rated power output equal to or greater than 1 W.