JPH09275245A - Semiconductor ld module - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a heat dissipating material to the large surface of a semiconductor LD module so as to improve semiconductor LD module in heat dissipating properties by a method wherein the heat dissipating material is provided in a part of the upside and sides of a package. SOLUTION: A package 10 is nearly a rectangular parallelepiped, where a large number of heat dissipating materials are provided in the upside 11 and side faces 12 and 13 of the package 10 upright. A terminal is provided in the package 10, the edge face of the package 10 can be dismounted, and the upside 11, the sides 12 and 13, a base 15, and the other edge face 16 where an optical fiber 4 is led out are formed in one piece. The heat dissipating member 2 is formed like a square pillar and brazed to the package 10. The edge face 14 of the package 10 is provided with a rectangular opening 5, and a terminal 30 is arranged in the opening 5. The terminal 30 is composed of a metal electrode 41 provided in the outer side of the package 10 protruding and a recessed electrode provided in the inner side. A protrudent electrode provided in the edge of an insulating board where electronic parts are mounted is plunged in the recessed electrode.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a semiconductor LD module having excellent heat dissipation.

[0002]

2. Description of the Related Art As a conventional semiconductor module, Japanese Patent Laid-Open No.
The thing described in 3-296288 is known. this is,
An LD (laser diode), a heat sink, a PD (photodiode), a lens, a Peltier element, etc. are mounted in a substantially rectangular parallelepiped package. As shown in FIG. 4, a terminal 21 for electrically connecting an electronic component in the package and an external device is arranged on a side surface of the package 20, and an optical fiber 22 for transmitting a signal of the LD is provided from one end surface.
Has been pulled out. A Kovar guard is provided directly under the upper surface 20B. In such a module, heat dissipation of the package 20 is important in order to efficiently operate an element such as an LD. Package 20 with this technology
Radiating fins (not shown) are provided on the bottom surface and the other end surface 20A to improve heat radiation.

[0003]

However, in the above technique, since the terminals are arranged on the side surface of the package surface having the larger area, the position where the heat radiation fins are provided is the end surface having the smaller area, and the heat radiation efficiency is maximized. I can't get rid of it. The upper surface 20B is made of Kovar, which has a low thermal conductivity because it is an electric weld that hermetically seals the inside. Even if fins are provided there, improvement in heat dissipation cannot be expected so much.

[0004]

SUMMARY OF THE INVENTION The present invention has been made to solve the above problems, and is to devise the arrangement of heat radiating members and the structure of terminals so as to improve the heat radiating property. That is, the semiconductor LD module of the present invention is characterized in that the heat dissipation material is provided on at least a part of the upper surface and both side surfaces of the package.

A large number of rod-shaped bodies or plate-shaped bodies are provided at predetermined positions of the package as the heat radiation material so that the surface area can be maximized. The heat dissipating material and the package surface on which the heat dissipating material is disposed are made of a highly thermoconductive material such as copper or an alloy of copper and tungsten. Further, as a means for forming the heat dissipation material on the package, it is possible to integrally form the heat dissipation material with the package by metal injection molding, or to separately manufacture the package and the heat dissipation material and bond them by brazing or the like.

On the other hand, it is preferable that the terminals for electrical connection inside and outside the package are arranged on one end surface of the package, and the optical fiber for transmitting the signal of the LD is arranged on the other end surface.
The end face on which the terminals are arranged may be a lid when mounting an electronic component such as an LD in the package. That is, this end face is used as an opening, and the electronic component is inserted into the package through the opening. Specifically, the terminal is composed of a convex electrode connected to an internal electronic component and a concave electrode fitted to the convex electrode, fixed to the end face of the package, and connected to the outside. By using the terminal as a plug-in type electrode, the terminal can be arranged on the end surface of the package having a small area, and the electrical connection between the internal electronic component and the terminal exposed on the package lid can be ensured. Here, the width of the terminal is preferably 1/2 or less of the width of the end face. The end surface of the package in which the terminals are arranged is made of a low thermal conductive material.

[0007]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the present invention will be described based on specific examples. 1 is a perspective view showing the external appearance of the LD module of the present invention, FIG. 2 is a side view showing the internal structure thereof, and FIG. 3 is a plan view of the internal structure. As shown in FIG. 1, the package 10 of the module of the present invention is a substantially rectangular parallelepiped, and has an upper surface 11 and both side surfaces 12, 1.
A large number of heat dissipating members 2 are projected on 3 (the surface that is continuous with the long sides of the top and bottom surfaces). One end surface 14 (a surface continuous with the short sides of the top and bottom surfaces) of the package 10 on which the terminals 3 are arranged can be removed, and the top surface 11, both side surfaces 12, 13, the bottom surface 15 and the other end surface from which the optical fiber 4 is drawn out. 16 are integrally formed. In this example, the parts other than one end surface of the package 10 are made of Cu: 40 wt%, W: 60 wt% copper alloy,
The heat dissipating material 2 was formed of Cu in the shape of a quadrangular prism, and both were adhered by Ag brazing, which has good solder elongation and good thermal conductivity. In this example, the heat radiating material 2 having a length of 3 mm and an end face of 1 mm square is arranged at 1 mm intervals. The one end face 14 on which the terminal 3 is arranged is made of Kovar, which has low thermal conductivity. A guard made of Kovar is arranged on the outer periphery of the end face 14 for electric welding.
Note that the end surface 14 projects from the end surface of the bottom surface 15 during electric welding.

The end face 14 of the package has a rectangular opening 5 in which the terminals 30 are located. The terminal 30 is shown in FIG.
As shown in FIG. 3, the metal electrode 31 is provided so as to project from the outer surface of the package, and the concave electrode 32 is provided inside the metal electrode 31. The concave electrode 32 is formed by metalizing the electric wiring on the laminated three layers of alumina plates, firing the metal wiring, and then inserting the metal wiring into the opening to seal the gap. The intermediate alumina plates are retracted with respect to the upper and lower alumina plates, and convex electrodes 40 described later are inserted therein. Metal thin film 33 is formed on the lower surface of the upper alumina plate and the upper surface of the lower alumina plate,
The metal electrode 31 on the outside of the package and the metal thin film 33 are connected to each other to electrically connect them.

On the other hand, the convex electrode 40 to be inserted into the concave electrode 32 is provided at the end of the AlN insulating substrate on which electronic parts such as LD are mounted. In this example, a plurality of rod-shaped metal foams are arranged in parallel as the convex electrode 40, and the solder portion 41 is provided at the tip thereof.
Was provided. The concave electrode 40 is electrically connected to the thin film electrode 6 on the substrate.

A procedure for mounting electronic components in the above package will be described with reference to FIGS. First, the semiconductor LD device 7 is mounted on the insulating substrate 8 of AlN via the submount.
Implement on top. Next, the PD 9 or the like previously mounted on the ceramic block is mounted on this substrate. LD7, PD9
Etc. are connected to the thin film electrode 6 of the substrate 8 by wire bonding, and this electrode 6 is connected to a convex electrode 40 protruding in a comb shape from one end of the substrate 8. A lens 50 is attached to the other end of the substrate 8.
Then, the upper surface of the electronic cooling element 51 (Peltier element) is bonded to the substrate by soldering via a metal plate. This composite is inserted from the open end surface of the package 10, and the composite and the package 10 are soldered by heating. Finally, the package end face with integrated terminals is attached to the opening and adhered by electric welding. At this time, the temperature of the convex electrode 40 rises due to welding, the solder at the tip flows, and the electrical connection with the concave electrode 32 is strengthened.

Since the conventional package has a structure in which the upper surface can be removed, the LD is internally formed with the upper surface opened.
It was possible to connect the terminals on the side of the package and the electronic parts by wire bonding. Since the upper surface of the package of the present invention cannot be removed, it is not possible to mount electronic components inside and then connect them by wire bonding. Therefore, one end face is used as a lid when mounting electronic components inside.

The other end surface 16 of the package 10 is formed with a drawing hole for the optical fiber 4. That is, the optical coupling part of the optical fiber in the package is the same as that of the conventional module (see Japanese Patent Laid-Open No. 3-296288).

As described above, by disposing the heat dissipation material on the surface of the package surface having the larger area (the upper surface / side surface in the above specific example) and providing the terminal on the surface having the smaller area (the end surface in the specific example), the module It is possible to maximize heat dissipation. In particular, the internal parts of the package and the terminals have a plug-in structure so that the electrical connection between the two can be easily ensured. In addition, the terminal is as small as possible, for example, the width a of the terminal is the width b of the end face (see FIGS. 1 and 3).
It is preferable to set to 1/2 or less. Make the terminals smaller,
By arranging it on the end surface of the package having low thermal conductivity, it is possible to radiate heat more efficiently. With the above configuration, the thermal resistance, which was 10 ° C./W in the conventional module (FIG. 4), can be reduced to 5 ° C./W.

[0014]

As described above, according to the module of the present invention, the internal parts of the package are connected to the terminals by the plug-in type electrodes, and the terminals are formed on the end surface having the small area, so that the surface having the large area is formed. A heat dissipating material can be arranged to improve heat dissipation.

[Brief description of drawings]

FIG. 1 is a perspective view of a module of the present invention.

FIG. 2 is a side view showing the internal structure of the module of the present invention.

FIG. 3 is a plan view showing the internal structure of the module of the present invention.

FIG. 4 is a perspective view showing a conventional module.

[Explanation of symbols]

10 Package 11 Top 12,13 Side 14,16 End 15 Bottom 2 Heat dissipation material 30 Terminal 31 Metal terminal 32 Recessed electrode
33 Metal thin film 4 Optical fiber 5 Opening 6 Thin film electrode 7 LD
8 substrate 9 PD 50 lens 51 thermoelectric cooler

Claims (8)

[Claims] 1. A semiconductor LD element that emits light, an optical fiber that transmits the optical signal, a package in which the semiconductor LD element is hermetically sealed and the optical fiber is pulled out, an electronic component inside the package and an external device are electrically connected. And a heat dissipation material provided on at least a part of the upper surface and both side surfaces of the package.
D module. 2. A terminal is arranged on one end surface and an optical fiber is drawn out from the other end surface.
The semiconductor LD module described. 3. The semiconductor LD module according to claim 1, wherein the heat dissipation material is a large number of rod-shaped bodies or plate-shaped bodies. 4. The terminal is a convex electrode connected to an internal electronic component, and is fitted to the convex electrode, and is fixed to an end face of the package.
The semiconductor LD module according to claim 1, wherein the semiconductor LD module comprises a concave electrode connected to the outside thereof. 5. The semiconductor LD module according to claim 2, wherein the width of the terminal is 1/2 or less of the width of the end face. 6. The semiconductor LD module according to claim 1, wherein at least one of the upper surface and the side surface of the package is made of a material having high thermal conductivity. 7. The semiconductor LD module according to claim 2, wherein the end face of the package in which the terminals are arranged is made of a material having a low thermal conductivity. 8. The end face of the package, in which the terminals are arranged,
The semiconductor LD module according to claim 2, wherein the semiconductor LD module is a lid part for mounting an electronic component therein.