JPH03227084A - Assembly of semiconductor - Google Patents

Abstract

PURPOSE:To move a laser chip to a prescribed position so as to enable the light emitting point of a laser to be uniquely fixed to a sub-mount by a method wherein a laser chip is pressure-joined to a sub-mount protrudent part and held for a some time at a temperature higher than the melting point of solder. CONSTITUTION:A laser chip 3 is die-bonded to a sub-mount 1 by a method that the laser chip 3 whose assembly surface is coated with a metallized layer 2, a sub-mount 1 is coated with a metallized layer 2, the chip 3 and the sub- mount 1 are made to stand for a some time at a temperature higher than the fusing point of solder, and then the sub-mount 1 and chip 3 are cooled. Then, when a voltage is applied between the upper part of the laser chip 3 and the lower part of the sub-mount 1 to enable a current larger than a laser oscillation threshold current flows between them, a laser beam is emitted from a light emitting point 4. By this setup, the surface tension of solder acts on a laser chip to move it so as to uniquely fix the light emitting point of the laser chip to a sub-mount.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a method for assembling a semiconductor laser used as a light source for compact discs and the like.

[Conventional technology]

FIG. 8 is a perspective view showing a conventional semiconductor laser assembly method.
In the figure, 1,61 is a rectangular parallelepiped shape? The laser chip is mounted at an angle of 1° to 8° above the S1 sag mount, 31 ha sub mount + 51, and 41 ha is the light emitting point of the laser beam.

Next, the operation will be explained. The laser chip 31 is firmly bonded onto the submount I5) by supplying solder. Next, a voltage is applied between the upper part of the laser chip (31) and the lower part of the submount 61.

[Problem to be solved by the invention]

Since the conventional semiconductor laser assembly method was configured as described above, there was a problem in that the positional accuracy of the light emitting point 41 was not uniquely determined with respect to the submount due to the assembly accuracy.

The present invention has been made to solve the above-mentioned problems, and its object is to provide a semiconductor assembly method in which the position of the laser light emitting point can be uniquely determined with respect to the submount.

[Means to solve the problem]

In the semiconductor assembly method according to the present invention, the submount is formed into a convex shape only at the part where the laser chip is assembled, a metallized layer is applied to the convex part and the assembly surface of the laser chip, and the laser chip is attached to the convex part of the submount. After the solder is crimped, the solder is held at a temperature above the melting point of the solder for a while.

[Effect]

In the semiconductor assembly method of this invention, by holding the solder at a temperature higher than its melting point for a while, the surface tension of the solder is applied to the laser chip so that the laser light emitting point is uniquely determined with respect to the submount. to move the laser chip.

[¥Example]

An embodiment of the present invention will be described below with reference to the drawings.

In Figure 1, (31 is the laser chip, l) is the part where the laser chip +31 is mounted, and is molded into a two-convex shape. The north metallized layer 1.4), which is erupted only in the shaped part, is the laser emission point.

Next, the operation will be explained. +2 metallized layers on the assembly surface
After applying the metallized layer 121 of the convex submount, the laser chip 13) was prepared by leaving it at a temperature above the melting point of the solder for a while, and then cooling it.
) is die-bonded to the submount (1). Then,
By applying the IK voltage to the upper part of the laser chip 131 and the lower part of the submount 15), the laser oscillation threshold current ta increases during this time 1[I5! Flows, the light emitting point) 41
More laser light is emitted.

〔Effect of the invention〕

As described above, according to the present invention, the laser chip is mounted on the submount convex portion vc! After f-bonding, the structure is such that it is held at a temperature above the melting point of the solder for a while, so that the surface tension of the solder acts on the laser chip so that the laser emission point is uniquely determined with respect to the submount while the solder is held at high temperature. Then, the laser chip is moved to a predetermined position.

4゜

[Brief explanation of drawings]

-g FIG. 1 is an exploded perspective view showing a semiconductor assembly method according to an embodiment of the present invention, and FIG. 2 is a perspective view showing a conventional semiconductor assembly method. 11 is a convex submount, and 41 is a metallized layer. 31 is a laser chip, and 41 is a light emitting point. In addition, in the figure, the same reference numerals indicate the same or different parts.

Claims (1)

[Claims] A submount used for die bonding of a semiconductor laser is formed into a convex shape only in the part where the laser chip is assembled, a metallized layer is applied to the convex part and the assembly surface of the laser chip, and the laser chip is crimped to the convex part of the submount. A semiconductor assembly method characterized by holding the solder at a temperature higher than the melting point of the solder for a while.