JPH03169092A - Semiconductor laser device - Google Patents

Abstract

PURPOSE:To improve heat radiation of a device by fitting the projection of heat radiating member excelleng in heat conductivity in the recess provided at the other main face of a semiinsulating substrate where hetrojunction structure is made in one main face. CONSTITUTION:This is equipped with a semiconductor element, where hetero junction is made at one main face of a semiinsulating substrate 3 and a recess 3a is made at the other main face, and a heat radiating member 1, which has a projection 1a of semiconductor element and is excellent in heat conductivity. That is, since a light emitting area (active layer) is close to a metallic block 1 for heat radiation, heat conductivity is favorable, and the heat generated in the active layer is radiated more speedily to the outside, and it never gives the effect to operation by heat accumulation. Hereby, it is suitable for the radiation of heat, and the reliability can be improved.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a semiconductor laser device with improved heat dissipation.

[Conventional technology]

FIG. 3 is a sectional view showing a conventional semiconductor laser device. In the figure, (2) is the negative electrode, (4) is the base shape ▲l1
, a lower cladding layer made of GaxAs, (6) an active layer made of p-type All-yGayAg, and (6) a p-type active layer made of p-type All-yGayAg.
The lth upper cladding layer of the type ▲it-xGax▲-, (
7) Ha! l-type G & ▲false υ block layer, (8) is p
This is a cladding layer above Pit 2, which is of type ▲1!1-xa-xAI. (9) is a contact layer of p-type G & ▲a to obtain an open junction between the ▲l1-xGazAs layer and the electrode, (+(l is the positive electrode, (to) is the heat dissipation Metal parts with good quality, for example, blocks made of ▲g, MO, etc.
ω is an n-type GaAs substrate.

The semiconductor laser device thus constructed is manufactured as follows. This will be explained based on FIG. 4. First, as shown in FIG. 4(a), on one main surface of the n-type G&All substrate (to), an n-type epitaxial μ layer which becomes the lower cladding layer (4) and an active layer (5) are formed. , the first upper cladding layer (6) and the p-type epitaxial μ layer, which will become the block layer (7), are formed one after another.
As shown in )), a resist agent 1 is applied onto the block layer (7) and irradiated with light through a photomask α4. Next, as shown in FIG. 4(0), the exposed areas of the resist agent O are developed and removed to form a pattern.
The GaA* block layer (7) is selectively removed using a mixed solution of 4011 and H202. To this, Meichichin 4 drawings (
As shown in li), a tapered groove is formed in the block layer (7). Next, after removing the mist pattern 0,
As shown in FIG. 4 (●), a semiconductor element having a grooved heterostructure is formed by subjecting the second upper cladding layer (8) and the contact layer to epitaxy μ. 'Next, as shown in Figure 4Cf>, after forming a positive electrode aG on the main surface on the side of the epitaxial layer and forming a negative electrode (2) on the other main surface,
When hung on a metal block, the semiconductor laser device is completed.

Next, the operation will be explained. By applying a voltage between the positive electrode 0o and the negative electrode (2), the holes injected into the positive electrode are narrowed by the block layer (7), and the holes are trapped in the active layer (5).
) flows into the center of the The holes are injected from the electrode (2) and flowed into the active layer (5), along with the holes that form the duplication μ between the lower cladding layer (4), the first upper cladding layer, and the active layer (5).
Active layer (5) due to band difference due to heterojunction
They are sealed inside, recombine, and emit light. The generated light is confined within the active layer (5) due to the refraction difference between the lower cladding layer (4), the first upper cladding layer (6), and the active layer (5). Generated; heat is generated from the board (3) and the heat dissipation block (self)
is transmitted and released to the outside.

[Problem to be solved by the invention]

Although the operating characteristics of semiconductor laser devices are sensitive to temperature,
Conventional semiconductor laser devices are constructed as described above, so even though the other main surface of the substrate (to) is bonded to the heat dissipation block material (to), the block edge is separated from the light emitting region. Therefore, there were problems in that heat dissipation was poor and the active layer (5) was easily deteriorated.

The present invention has been made to solve the above-mentioned problems, and aims to provide a semiconductor laser device that is suitable for dissipating generated heat and that improves b1 reliability.

[Means to solve the problem]

A semiconductor laser device according to the present invention includes a semiconductor element in which a heterojunction structure is formed on one principal surface of a semi-insulating substrate and a recessed portion on the other principal surface, and a semiconductor element having a convex portion with good thermal conductivity. It is equipped with a heat dissipation member.

[Effect]

The semiconductor laser device according to the present invention has good heat dissipation because the light emitting region (active layer) is close to the heat dissipation metal psec.
The heat generated in the active layer is dissipated to the outside very quickly, and the operation is not affected by heat accumulation, so that normal operation can be performed.

〔Example〕

An embodiment of the present invention will be described below with reference to the drawings. Nak
, the description of parts that overlap with the description of the prior art will be omitted as appropriate. FIG. 1 is a sectional view showing the structure of a semiconductor laser device according to an embodiment of the present invention. In the figure, (2)
and (4> to 110 are the same as the conventional ones, (1) is a metal block for heat dissipation in which a convex part is formed, (1&) is the convex part, and (3) is a metal block in which the convex part is inserted. A GaAg substrate having four parts, (4) is a recess.

The semiconductor laser device configured as described above is manufactured as follows. On the GaAs substrate (3), a lower cladding layer (4), an active layer (5), a first upper cladding layer (6),
Block layer, second upper cladding layer (8), contact layer (
9) Form the kayak and positive electrode GO, but up to this step,
FIG. 4 of the conventional technology (same as the explanation of 0 to <1>,
The explanation will be omitted.

Next, the concave portion (3&) of the GaAg substrate (3) is formed, and the method for forming it will be described below. This will be explained based on FIG. First, as shown in Fig. 2 (&), GaAl
Resist agent 0 is applied onto the other main surface of the substrate (3), and light is irradiated onto this through a photomask. Then the second
As shown in Figure (b), the exposed areas of resist agent 0 are developed and
Remove and pattern. This resist pattern (own)
as a mask, etching solution, for example, NH40H and A2
The pGaAs substrate (3) is selectively removed up to just before the lower cladding layer (4) using a mixed solution with O2.

Therefore, as shown in FIG. 2(O), a concave groove (3) is formed in the center of the other main surface of the GaAII substrate (3).
0 is formed Next, after removing the resist pattern 0, the negative electrode (2) is made of GaA as shown in FIG. 2(d).
8 Formed on the other main surface of the substrate (3) 0 In this way,
A semiconductor element is formed.

On the other hand, a square material such as Ag-IJo having good thermal conductivity is metal-processed to form a protrusion (1a) so as to be inserted into the groove (3&) of the semiconductor element. This is υ, block (1)
is obtained.

By joining the grooves (3a) of these semiconductor elements and the convex portions (one color) of the block (1) with solder or the like, a semiconductor laser device is completed.

During operation of such a semiconductor laser device, the positive electrode an
The holes and electrons injected into the negative electrode (2) recombine in the active layer (5) and emit light, but the heat generated at this time is transferred to the convex portion of the substrate (3) and the heat dissipation block. The heat dissipates through the heat dissipation block (10) and escapes to the outside through the heat dissipation block (1).In this case, the distance between the light emitting region (active layer) and the heat dissipation block is much shorter than in the conventional one. ,
This improves heat dissipation, provides stable operation, and improves reliability.

By the way, normally, a photodiode attached to the rear of the semiconductor laser device is used to monitor the oscillated laser beam, but in this embodiment, when the semiconductor laser element is installed on the heat dissipation block (1), Since the concave part (30) of the GaAs substrate is fitted into the convex part (1&) of the block, the element can be positioned with good reproducibility, and alignment with the photodiode can be easily performed.

Although the above embodiment shows the case where an n-type substrate (3) is used, it is also possible to use a p-type substrate, and in that case, the conductivity types of the respective elongated layers are opposite to each other. Good.

In addition, instead of the GaAi substrate (3), a semiconductor laser device may be made using an engineered nP substrate or any other substrate. Furthermore, here, the current blocking layer of the Ebitaxia ρ layer is made of SAS (Self Aligre4 Struot+).
Although the case of a semiconductor laser device of xre) type is shown,
A similar effect can be achieved in a semiconductor laser device having a type S (Enfi@rStriI) type or any other type of structure.0 [Effects of the Invention] As described above, according to the present invention, one of the main effects can be achieved. Since the convex part provided on the heat dissipating member with good thermal conductivity is fitted into the concave part provided on the other main surface of the semi-insulating substrate with a heterojunction structure formed on the surface, the heat dissipation of the device is improved. This has the effect of improving the reliability of the semiconductor laser device.

[Brief explanation of the drawing]

FIG. 1 is a cross-sectional view of a semiconductor laser device showing an embodiment of the present invention, FIG. Cross-sectional view of laser device, !@4 Figures (a) to (f) are cross-sectional views showing the manufacturing process of a conventional semiconductor laser device. In the figure, (1) is a metal block, and ('') is a convex Part, (
3) is a G&All substrate, and (3&) is a concave portion. In each figure, the same symbols indicate the same or equivalent parts.

Claims (1)

[Claims] A semiconductor element having a heterojunction structure formed on one main surface of a semi-insulating substrate and a recess formed on the other main surface, and a heat dissipating member with good thermal conductivity having a protrusion to be inserted into the recess of the semiconductor element. A semiconductor laser device consisting of.