JPH02281782A - Semiconductor laser array device - Google Patents

Abstract

PURPOSE:To obtain continuous oscillation by placing a two-dimensional semiconductor array, wherein plural pieces of one-dimensional semiconductor arrays are placed in layer shape between insulating plates excellent in heat conductivity, on a heat radiating member through the insulating plates. CONSTITUTION:Plural pieces of one-dimensional semiconductor arrays 1 are placed in layer shape between insulating plates 2 excellent in heat conductivity so as to constitute a two-dimensional semiconductor laser array 4, and this two-dimensional semiconductor laser array 4 is placed on a heat radiating member 5 through the insulating plates 2. For the material of the insulating plates 2, BN is used which is almost the same as GaAs being laser crystals in point of cost and in heat expansion coefficient. Hereby, the heat generated from the one-dimensional semiconductor laser array 1 is transmitted to the heat radiating member 5 through the insulating plate 2 excellent in heat conductivity, and heat radiation is performed enough, and the temperature rise of the semiconductor laser array device is suppressed, and also continuous oscillation becomes possible.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a high-output semiconductor laser array device used for excitation and processing of solid-state laser crystals.

Conventional technology semiconductor lasers have a narrow spectral width and high efficiency, and Nd
:Since efficient excitation can be achieved by matching the wavelength to the absorption spectrum of a solid-state laser crystal such as a YAG crystal, it has recently attracted attention as a solid-state laser excitation light source in place of conventional lamps. When a semiconductor laser is used as an excitation light source for a solid-state laser, the excitation light source needs to have a high optical density. The size of the emission area of a semiconductor laser is 1
Since it is approximately 0 μm x 2 μm, it is possible to obtain extremely high light density by creating a semiconductor laser array in which many laser light emission points, which are light emitting parts, are arranged one-dimensionally (linearly) or two-dimensionally (planarly). It is. The overall efficiency when a semiconductor laser is used as the pumping light source for a YAG laser is 10%, since the semiconductor laser's electrical-to-optical conversion efficiency is 30% and the YAG laser's input pumping light-to-laser output optical conversion efficiency is 30%. %, which is more than 10 times that in the case of lamp excitation. Furthermore, there is no heat generation in the crystal due to absorption of light of extra wavelengths, and cooling of the YAG laser is also reduced. Conventionally, in order to achieve a high output of 1 q with a semiconductor laser, it is necessary to arrange a large number of laser beam emission points with high density two-dimensionally, that is, on a plane. By the way, since semiconductor lasers use the open plane of a crystal as a resonator, it is not easy to monolithically arrange laser light emitting points on two substrates. Therefore, it is conceivable to use a bar-shaped semiconductor laser array in which laser beam emission points are arranged in the negative dimension, and to further arrange this in two dimensions.

Problems to be Solved by the Invention When the light emitting points of semiconductor lasers are arranged in high density, heat generation becomes a problem. In particular, the threshold current value of a semiconductor laser is sensitive to temperature, and a phenomenon occurs in which optical output is saturated due to heat generation of the element. Furthermore, operation at high temperatures significantly shrinks the field of the device. For example, if the element temperature increases by 10 degrees, the lifetime will be halved. Therefore, in order to increase the maximum optical output, it is important to dissipate heat efficiently and keep the element temperature low, but it is not possible to simply place a two-dimensional semiconductor laser array on a heat sink and fuse it. Therefore, there was a problem that heat radiation was not sufficiently carried out. Note that if heat dissipation is poor, it is very difficult to obtain continuous oscillation, and only slow pulse operation with a short pulse width (1 μs or less) and slow repetition can be performed.

Therefore, an object of the present invention is to provide a semiconductor laser array device that can solve the above problems.

Means for Solving the Problems In order to solve the above problems, the semiconductor laser array device of the present invention uses a one-dimensional semiconductor laser array in which a plurality of laser beam emission points are arranged one-dimensionally. A two-dimensional semiconductor laser array is constructed by arranging a plurality of semiconductor lasers in a layer between insulating plates, and this two-dimensional semiconductor laser array is placed on a heat dissipating member via the insulating plates.

Operation In the above configuration, the heat generated from the -dimensional semiconductor laser array is conducted to the heat radiating member via the insulating plate having good thermal conductivity, and the heat is sufficiently radiated.

Therefore, the temperature level of the semiconductor laser array device is suppressed, and continuous oscillation is also possible.

Example Hereinafter, one embodiment of the present invention will be described based on the drawings.

FIG. 1 is an external perspective view of a semiconductor laser array device, and FIG. 2 is a perspective view of the main parts and an exploded perspective view of the device.

In FIGS. 1 and 2, reference numeral 1 denotes a bar-shaped one-dimensional semiconductor laser array composed of, for example, ten laser beam emission points (also referred to as light-emitting points) arranged one-dimensionally at intervals of 100 μm, and has a length of 1. .2 darkness, thickness 100 μm, 1 resonator length 250 μm. Five -dimensional semiconductor laser arrays 1 are arranged in parallel, and insulating plates 2 made of a material with good thermal conductivity are interposed between them and on both sides to form a layered structure. An insulating spacer 3 made of the same material as the insulating plates 2 is interposed between each insulating plate 2 on the side opposite to the semiconductor laser array 1, thereby forming a two-dimensional semiconductor laser array 4.

Furthermore, this layered two-dimensional semiconductor laser array 4
is placed on the heat sink 5 such that its end face on the insulating spacer 3 side contacts the surface of the heat sink (heat dissipation member) 5. The material of the insulating plate 2 is as follows:
Diamond is the best in terms of thermal conductivity, but 8N is better in terms of cost and thermal expansion coefficient, which is almost the same as GaAs, which is a laser crystal. B
The thermal conductivity of N is one-third that of diamond, but is more than twice that of copper, so 8N is used in this example. The thickness of the insulating plate 2 is 100 μm, and as shown in FIG. 2, the upper and lower surfaces are made of Cr.
- A metallized pattern a of Pt-Au is applied. Note that a solder material such as Au-8n or Pb-8n is deposited on the gold pattern so that it can be fused to the -dimensional semiconductor laser array 1. Since the solder material has poor thermal conductivity, its film thickness is made as thin as 3 μm.

The two-dimensional semiconductor laser array 4 is fused onto a gold-plated copper heat sink 5 using a solder material such as Pb3n, and of course the insulating spacer 3 is interposed between the heat sink 5 and the heat sink 5. This is to increase the heat conduction area. A gold metallized pattern a is also applied to the surface of the insulating spacer 3. Note that the electrode terminal 6 on the heat sink 5 side and the insulating plates 2 on both sides as electrode terminals of the two-dimensional semiconductor laser array 4 are connected by a gold wire 7, and in order to flow a large current close to IOA, the gold wire 7
The number of trees is about 50.

In the above configuration, the heat generated in each one-dimensional semiconductor laser array 1 is conducted to the heat sink 5 side via the insulating plate 2 and the insulating spacer 3, and the heat is sufficiently absorbed. Note that in FIG. m1 and FIG. 2, arrow A indicates laser light emitted from the two-dimensional semiconductor laser array 4.

Here, the current in the above semiconductor laser array device -
Figure 3 shows the output characteristics. Note that since the -dimensional semiconductor laser arrays 1 are connected in five overlapping rows, the applied voltage is about 10V. As can be seen from FIG. 3, the optical output on the 20W J3 was reduced by 1η with a current of 6A, and the conversion efficiency from electricity to laser light was 33%, a very good result. Since the area of the laser light emitting point, which is the light emitting part, is approximately 1 -, the optical density is 2 KW/cII, which has satisfactory characteristics as an excitation light source for a YAG laser. As the material of 3,
[1(Cu), in addition to diamond (C), for example, boron nitride (BN>, silicon carbide (S i C>),
beryllia <8eO), aluminum nitride <Al2N>
etc. are used.

Effects of the Invention As described above, according to the configuration of the present invention, sufficient heat radiation can be performed by conducting the heat generated from the -dimensional semiconductor laser array to the heat radiation member via the insulating plate with good thermal conductivity. Therefore, the life of the device is extended, and continuous oscillation can be performed with a large output. In particular, this semiconductor laser array device is suitable as a pumping light source for continuous operation of a slab-type solid-state laser, and by integrating a large number of blocks, it is possible to realize a highly efficient KWa continuous-wave slab-type solid-state laser. It is.

[Brief explanation of drawings]

FIG. 1 is an external perspective view of the semiconductor laser array device of the present invention, FIG. 2 is a perspective view of the main parts of the semiconductor laser array device,
FIG. 3 is a current-optical output characteristic diagram of the semiconductor laser array device. 1... -dimensional semiconductor laser array, 2... insulating plate,
3... Insulating spacer, 4... Two-dimensional semiconductor laser array, 5... Heat sink. Agent Yoshihiro Morimoto 1st translation 9. -Blow! Takashi 4 Hon Rede 7 Shi A 2-8 Hayashi 4 Ken 5--1-Hee F Shin 2 Fig. Fig.? Current (A)

Claims (1)

[Claims] 1. Construct a two-dimensional semiconductor laser array by arranging a plurality of one-dimensional semiconductor laser arrays in which a plurality of laser beam emission points are arranged one-dimensionally between insulating plates with good thermal conductivity, and A semiconductor laser array device in which a two-dimensional semiconductor laser array is placed on a heat dissipation member via an insulating plate.