JPS609189A - Semiconductor laser device - Google Patents

Abstract

PURPOSE:To obtain a high output while operating an APC by attaching an insulating film on the outside of a metallic film on one cavity end surface. CONSTITUTION:SiO2 films 2 in 2,750Angstrom thickness are attached on both cleavage planes of a laser chip 1 through a sputtering method. A gold film 3 in 1,000Angstrom thickness is attached only on one cleavage plane. An SiO2 film 6 in 1,000Angstrom thickness is attached on the gold film 3. The laser chip 1 is bonded with a radiator 4 made of copper by using tin. The metal 3 cannot protrude because the outermost section of a cavity end surface is constituted by not a metal but the insulating film 6 in the laser element 1. Accordingly, beams can be lead out of the side, to which the gold film 3 is attached, of a cavity even under the state in which the laser element is bonded with the radiator 4, and an APC can be operated.

Description

[Detailed description of the invention] Industrial applications The present invention relates to a semiconductor laser device.

Conventional configuration and its problems In order to obtain high output f iQ from a semiconductor laser, conventionally, the first
As shown in the figure, an 8102 film 2 with a thickness of 1/2 (λ is the wavelength of the laser beam) is placed on one cavity surface of the laser element 1.
A method is used in which a gold film 3 is deposited on top of the gold film 3. According to such a structure, the laser light inside the cavity is reflected by the gold film 3, and almost no light is emitted from the end face of the cavity to which the gold film 3 is attached. Therefore, most of the laser light is extracted from the end face of the cavity to which the gold film is not attached. In this way, the oscillation threshold current is reduced, and high-output laser light can be extracted. However, the APC (Automatic
Power C1ntrol) In order to perform the entire operation, it is necessary to use light emitted from the back side of the cavity, so it is also necessary to use some light from the end face of the cavity to which the gold film 3 is attached.

By the way, when the laser element having the above-mentioned conventional structure is bonded onto the heat sink 4 as shown in FIG. The metal 5 and the gold film 3 become alloyed. As a result, no light can be extracted from the back side of the cavity. Therefore, the aforementioned AP
C operation cannot be performed.

OBJECTS OF THE INVENTION In view of the above-mentioned conventional drawbacks, the present invention provides a semiconductor laser device that can perform APC operation even when bonded to a heat sink.

Structure of the Invention In order to achieve all of the above objects, the semiconductor laser device of the present invention is a semiconductor laser device in which an insulating film, a metal film, and an insulating film are sequentially formed on one cavity surface.

DESCRIPTION OF EMBODIMENTS An embodiment of the present invention will be described below with reference to all the drawings. FIG. 3 shows the configuration of a central body laser device in one embodiment of the present invention.

First, a method for manufacturing a semiconductor laser device having this configuration will be described.

A 5102 film 2 having a thickness of 2760 mm is deposited on both cleavage planes of the laser chip 1 by sputtering. Next, a gold film 3 with a thickness of 1000 mm is deposited on only one cleavage surface. Further, an 8102 film 6 with a thickness of 1000 mm is deposited on the gold film 3. This laser chip 1 is bonded to a heat sink 4 made of copper using tin.

Since the thickness of the 5i02 film 2 is 2750 λ/2, the amount of light coming out of the cavity is
The structure is exactly the same as the laser shown in the figure.

Moreover, the oscillation threshold current is also the same. In this laser element 1, since the outermost part of the cavity end face is made of an insulating film 6 instead of metal, the metal 5 shown in FIG. 2 is repelled, and the metal 6 cannot rise up. Therefore, even when bonded to the heat sink 4, light can be extracted from the side of the cavity where the gold film 3 is attached, and the AP
C operation is possible.

FIG. 4 is a diagram showing the optical outputs that can be extracted from the front and rear of a laser having such a structure. In other words, the light from the rear (
Characteristic curve a) has a light output that is approximately 1/I0 of the light from the front (Special 1 (10-curve curve)), and is sufficient for APC operation. This is about 60% of the light when only film 2 is attached (characteristic curve C), and the oscillation efficiency is also high, resulting in high output.In addition, the laser device with 6 o n2 W output, 100
A life of over 00 hours was obtained.

Note that instead of the SiO2 films 2 and 6 used in this example, A
An insulating film such as 12O3 or 5i3Na may be used as a substitute for the gold film 3, and a metal film such as platinum or a laminated film of these metals may be used.

Effects of the Invention As described above, in the present invention, an insulating film is attached to the outside of the metal film on one end face of the cavity, and high output can be obtained and APC operation can be performed.

[Brief explanation of drawings]

FIG. 1 is a sectional view of a conventional semiconductor laser device, FIG. 2 is a diagram showing a conventional semiconductor laser device bonded to a heat sink, and FIG. 3 is a sectional view of an embodiment of the semiconductor laser device of the present invention. , FIG. 4 is a current-optical output relationship diagram in a semiconductor laser device according to an embodiment of the present invention. 2...5102 film, 3...gold film, 6...
...SiO2 film, a... Light output from the front, b
-...Light output from the rear surface, C...5102
Optical output of the laser device with only film 2. Name of agent: Patent attorney Toshio Nakao and 1 other person No. 1
Figure 2

Claims (1)

[Claims] An insulating film is provided on one cavity surface of a semiconductor laser. A semiconductor laser device characterized in that a metal film and an insulating film are sequentially laminated.