JPH05267794A - Chip carrier fixing structure of semiconductor laser module - Google Patents

Abstract

PURPOSE:To enable an optical system to be kept high in long-term stability without impeding a semiconductor laser in heat dissipation. CONSTITUTION:A semiconductor laser 1 is mounted on a heat sink 2, and a chip carrier 3 is placed on the heat sink 2. The chip carrier 3 is mounted on a base 4. The chip carrier 3 is composed of a heat dissipating piece 3A high in thermal conductivity, a ceramic electrode 3B brazed to the heat dissipating piece 3A, and a welded piece 3C provided to both the sides of the heat dissipating piece 3A each. The base 4 is composed of a heat dissipating plate 4A and a welded plate 4B brazed to both the sides of the heat dissipating plate 4A each. The welded piece 3C and the welded plate 4B are welded.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a chip carrier fixing structure for a semiconductor laser module.

[0002]

2. Description of the Related Art In a semiconductor laser module, a semiconductor laser, a condenser lens, a monitor photodiode, etc. are housed in a case, and an optical fiber is fixed to the side surface of the case. Also, since the output light of the semiconductor laser fluctuates due to heat,
An electronic cooling element is used for the purpose of keeping the temperature of the semiconductor laser constant.

Next, the structure of a conventional semiconductor laser module will be described with reference to FIG. 2, 1 is a semiconductor laser, 2 is a heat sink, 5 is a chip carrier, 6 is a base, 7A is a condenser lens, 7B is a monitor photodiode, 7C is an electronic cooling element, 7D is a case, 7E is a lid,
8A is an optical fiber ring, 8B is a ferrule, and 8C is an optical fiber.

The semiconductor laser 1 is mounted on a heat sink 2, and the heat sink 2 is mounted on a chip carrier 5.
The chip carrier 5 is fixed to a base 6, and a condenser lens 7A is attached to the base 6. The monitor photodiode 7B is attached to the base 6, and the electronic cooling element 7C is attached between the bottom surface of the base 6 and the case 7D. The case 7D is sealed with a lid 7E. Ferrule 8
The optical fiber 8C protected by B is an optical fiber ring 8A.
It is fixed to the side surface of the case 7D via YAG laser welding or the like.

Next, a detailed structure near the chip carrier 5 shown in FIG. 2 will be described with reference to FIG. The chip carrier 5 shown in FIG. 3 includes a heat dissipation piece 5A and a ceramic electrode 5B. The ceramic electrode 5B is brazed onto the heat dissipation piece 5A, and the chip carrier 5 is fixed to the base 6 with solder 6A. The semiconductor laser 1 is connected to the ceramic electrode 5B by the bonding wire 5C, and the heat sink 2 is electrically connected to the heat dissipation piece 5A by the bonding wire 5C.

[0006]

The semiconductor laser 1 shown in FIG.
In order to reduce the thermal resistance between the electronic cooling element 7C and the electronic cooling element 7C, the heat dissipation piece 5A of the chip carrier 5 and the base 6 are made of metal having high thermal conductivity. Therefore, since the chip carrier 5 and the base 6 cannot be fixed by welding, the chip carrier 5 and the base 6 are fixed by the solder 6A,
The solder 6A has a low melting point so that the heat of the solder 6A is not conducted to the semiconductor laser 1. However, the solder tends to undergo a creep phenomenon which is distorted over time. Therefore, the position of the semiconductor laser 1 changes with time, and there is a problem that the stability of the optical system cannot be ensured for a long period of time.

According to the present invention, a chip carrier is constituted by a heat dissipation piece having a high thermal conductivity, a ceramic electrode brazed on the heat dissipation piece, and welding pieces brazed on both side surfaces of the heat dissipation piece, and the base is made of heat conductive material. It consists of a high heat dissipation plate and welding plates that are brazed to both sides of the heat dissipation plate, and by welding the chip carrier welding piece and the base welding plate, long-term optics can be achieved without hindering the heat dissipation of the semiconductor laser. An object is to provide a chip carrier fixing structure that secures system stability.

[0008]

In order to achieve this object, according to the present invention, a heat sink 2 on which the semiconductor laser 1 is mounted, a chip carrier 3 on which the heat sink 2 is mounted,
The chip carrier 3 is provided with a base 4 on which the chip carrier 3 is placed, and the chip carrier 3 has a high heat conductivity, a heat dissipation piece 3A, a ceramic electrode 3B brazed on the heat dissipation piece 3A, and both side surfaces of the heat dissipation piece 3A. The base 4 is composed of a welding piece 3C, and the base 4 is composed of a heat radiating plate 4A having a high thermal conductivity and welding plates 4B brazed to both side surfaces of the heat radiating plate 4A. Weld plate 4B.

[0009]

Next, the chip carrier fixing structure according to the present invention will be described with reference to FIG. 3 in FIG. 1 is a chip carrier, 4
Is the base. The chip carrier 3 is composed of a heat dissipation piece 3A having a high heat conductivity, a ceramic electrode 3B brazed on the heat dissipation piece 3A, and welding pieces 3C brazed on both side surfaces of the heat dissipation piece 3A. The base 4 is composed of a heat dissipation plate 4A having a high heat conductivity and welding plates 4B brazed to both side surfaces of the heat dissipation plate 4A.

The semiconductor laser 1 has a bonding wire 3D.
Is electrically connected to the ceramic electrode 3B, and the heat sink 2 is electrically connected to the heat dissipation piece 5A by the bonding wire 5C. The welding piece 3C of the chip carrier 3 and the welding plate 4B of the base 4 are welded by the welding portion 4C by YAG laser or the like. The electronic cooling element 7C is attached to the bottom surface of the base 4 as in FIG. Heat dissipation piece 3
A having a high heat conductivity is used for A and the heat dissipation plate 4A, and a good weldability such as SUS304 is used for the welding piece 3C and the welding plate 4B.

[0011]

According to the present invention, the chip carrier is constituted by a heat dissipation piece having a high thermal conductivity, a ceramic electrode brazed on the heat dissipation piece, and welding pieces brazed on both sides of the heat dissipation piece. The base consists of a heat dissipation plate with high thermal conductivity and welding plates that are brazed to both sides of the heat dissipation plate, and by welding the welding piece and the welding plate, the thermal resistance between the semiconductor laser and the electronic cooling element is improved. Since it can be made smaller and the chip carrier and base can be fixed by welding,
It is possible to secure the stability of the optical system for a long time without hindering the heat radiation of the semiconductor laser.

[Brief description of drawings]

FIG. 1 is a chip carrier fixing structure according to the present invention.

FIG. 2 is a configuration diagram of a semiconductor laser module according to a conventional technique.

FIG. 3 is a detailed structural diagram around the chip carrier 5 of FIG.

[Explanation of symbols]

 1 Semiconductor Laser 2 Heat Sink 3 Chip Carrier 3A Heat Dissipation Piece 3B Ceramic Electrode 3C Welding Piece 4 Base 4A Heat Sink 4B Welding Plate

Claims (1)

[Claims] 1. A heat sink on which a semiconductor laser (1) is mounted.
(2), a chip carrier (3) on which the heat sink (2) is placed, and a base (4) on which the chip carrier (3) is placed, and the chip carrier (3) is a heat sink (3A) with high thermal conductivity. , A ceramic electrode (3B) brazed on the heat sink (3A) and welding pieces (3C) brazed on both sides of the heat sink (3A). High heat sink (4A) and heat sink (4A)
It consists of the welding plate (4B) brazed to both sides of the chip, the welding piece (3C) of the chip carrier (3) and the welding plate of the base (4).
(4B) is welded to a semiconductor laser module chip carrier fixing structure.