JPH0951144A - Optoelectronic devices - Google Patents

Abstract

(57) [Summary] [Object] To provide an optoelectronic device having a multi-beam structure having stable light emission characteristics. An optoelectronic device comprising a multi-beam semiconductor laser chip formed by monolithically forming a plurality of semiconductor laser parts, wherein the multi-beam semiconductor laser chip is a support plate in which chip parts corresponding to the respective semiconductor laser parts are different from each other. Fixed directly to. The support plates are leads that are electrically independent of each other.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a technique effective when applied to a multibeam semiconductor laser used as a light source for an information processing device such as a laser printer, for example, an optoelectronic device.

[0002]

2. Description of the Related Art As one of optoelectronic devices, a multibeam semiconductor laser (optoelectronic device) having a multibeam semiconductor laser chip for emitting a plurality of laser beams (beams) in a single package is known. .

Regarding the multi-beam semiconductor laser, for example, “Electronic Materials”, February 1987, published by the Industrial Research Institute, 2 of the same year.
Published on the 1st of the month, it is described on pages 72-76.

In this document, in a monolithic laser, when an element is driven by ACC at 20 mW and a pulse current is applied to the element to measure the output variation of the element, increasing the pulse width causes a thermal effect. It is stated that a possible output reduction of the device was observed. Further, it is described that the oscillation spectrum also fluctuates during multi-beam operation in response to fluctuations in output.

[0005]

A conventional multi-beam semiconductor laser is assembled on a heat sink via a submount in order to ensure the assembling accuracy. However, when each semiconductor laser portion is individually driven, heat generated at that time is transferred to other semiconductor laser portions via the submount, and thermal crosstalk occurs as described in the above document, Output decreases.

An object of the present invention is to provide an optoelectronic device having a multi-beam structure, which has stable emission characteristics.

The above and other objects and novel features of the present invention will be apparent from the description of this specification and the accompanying drawings.

[0008]

The following is a brief description of an outline of typical inventions disclosed in the present application.

(1) An optoelectronic device comprising a multi-beam semiconductor laser chip formed by monolithically forming a plurality of semiconductor laser parts, wherein the multi-beam semiconductor laser chip has chip parts corresponding to the respective semiconductor laser parts mutually. It is fixed directly to a different support plate. The support plates are leads that are electrically independent of each other.

[0010]

According to the above means (1), in the multi-beam semiconductor laser chip, the chip portions corresponding to the respective semiconductor laser portions are directly fixed to mutually different leads. For this reason, the heat generated in each semiconductor laser portion is radiated through the lead (supporting plate) that supports each semiconductor laser portion. Therefore, even when one semiconductor laser portion is driven, the other semiconductor laser portion is driven. Thermal crosstalk is less likely to occur, and output characteristics are stable.

[0011]

Embodiments of the present invention will be described below in detail with reference to the drawings.

FIG. 1 is a sectional view of an optoelectronic device according to an embodiment of the present invention, FIG. 2 is a plan view of the optoelectronic device according to the present embodiment with a cap removed, and FIG. 3 is a view of the optoelectronic device according to the present embodiment. It is a perspective view showing an important section.

As shown in FIG. 1, the optoelectronic device of this embodiment comprises a plate-shaped stem 1 which is a main component of an assembly and a cap 15 which is airtightly fixed to the main surface side of the stem 1. There is.

The stem 1 is a circular metal plate (conductive plate) having a thickness of several mm. Four leads 2 to 5 are fixed to the stem 1. One lead 2 is electrically and mechanically connected to the lower surface of the stem 1.

The three leads 3, 4 and 5 penetrate the stem 1 and are insulated and fixed to the stem 1 via an insulating glass 6. The lead 3 is connected to an electrode of a light receiving element described later via a wire.

The portions of the two leads 4 and 5 projecting toward the main surface side of the stem 1 have a wide structure from the middle, and the wide support plates 7 and 8 have the structure shown in FIGS. As shown, a single multi-beam semiconductor laser chip 9 is fixed via conductive bonding materials 10 and 11. Although the pair of support plates 7 and 8 are close to each other, they are electrically independent,
They are separated by a predetermined distance. In order not to cause a short circuit, for example, the support plates 7 and 8 are separated from each other by several tens of μm or more.

Therefore, the multi-beam semiconductor laser chip 9 is fixed to the separate leads 4 and 5 at two locations via the bonding materials 10 and 11.

The multi-beam semiconductor laser chip 9 has two resonators 12 and 13 extending in parallel as shown in FIG. That is, in the multi-beam semiconductor laser chip 9 of this embodiment, two semiconductor lasers adjacent to each other and independent from each other are formed, and the two semiconductor laser portions 20 and 21 are the multi-beam semiconductor laser chip 9 respectively. The pn junction portion is divided by the isolation groove 16 provided on the surface of, and, for example, the p electrode on the surface (not shown) is electrically connected to the leads 4 and 5 by the separate bonding materials 10 and 11. Although not shown, the exposed flat surface portion of the multi-beam semiconductor laser chip 9 is a common n-electrode. The n-electrode and the stem 1 are electrically connected by a wire 22 as shown in FIG. As a result, the external terminal of the common electrode of the multi-beam semiconductor laser chip 9 becomes the lead 2.

When a predetermined voltage is applied to the leads 2 and 4, a laser beam 23 is emitted from the resonator 12 of the semiconductor laser portion 20. When a predetermined voltage is applied to the leads 2 and 5, the laser beam 24 is emitted from the resonator 13 of the semiconductor laser portion 21. That is, two semiconductor laser parts 20 of a single multi-beam semiconductor laser chip 9,
21 can be controlled independently.

On the other hand, on the main surface of the stem 1, a laser beam 23 emitted from the lower end of the multi-beam semiconductor laser chip 9 is formed.
A light receiving element (photodiode) 25 that receives 24 and monitors the light intensity of the laser beams 23 and 24 is fixed.
The light receiving element 25 is fixed to an inclined surface 26 provided on the main surface of the stem 1 via a bonding material (not shown). An unillustrated upper surface electrode of the light receiving element 25 and the lead 3 are connected by a conductive wire 27. Therefore, if either the laser light 23 or 24 is received by the light receiving element 25,
A current will flow between the lead 2 and the lead 3.

On the other hand, a metal cap 15 having a window 30 is hermetically fixed to the main surface of the stem 1, and the multi-beam semiconductor laser chip 9, the light receiving element 25, the leads 3,
4, 5 and the like are sealed. The window 30 has a cap 15
It is formed by mounting the circular hole provided in the ceiling part of the so that it is covered with the transparent glass plate 31. Glass plate 3
1 is fixed to the cap 15 by the bonding material 32.

In the optoelectronic device of this embodiment, the two semiconductor laser portions 20, 21 of the multi-beam semiconductor laser chip 9 are used.
Are fixed to mutually different support plates (leads) 7 and 8, and heat is radiated from the separate support plates 7 and 8. Therefore, when one semiconductor laser portion 20 is being driven, even if the other semiconductor laser portion 21 is being driven, thermal crosstalk is less likely to occur, and output fluctuations are extremely small,
No longer affects use. As a result, stable output characteristics can be obtained.

The optoelectronic device of this embodiment can reduce the heat conduction between the semiconductor laser portions 20 and 21 of the laser array, and therefore can improve the operating life of the semiconductor laser portions 20 and 21.

The optoelectronic device of this embodiment has a structure in which the multi-beam semiconductor laser chip 9 is fixed to the tips of the leads 4 and 5, so that the manufacturing cost can be reduced.

Although the invention made by the present inventor has been specifically described based on the embodiments, the present invention is not limited to the above embodiments, and various modifications can be made without departing from the scope of the invention. Needless to say, for example,
Even if the multi-beam semiconductor laser chip has a structure having three or more semiconductor laser portions, the same effect as in the above embodiment can be obtained if the number of semiconductor laser portions is set to the supporting plate.

[0026]

The effects obtained by the typical ones of the inventions disclosed in the present application will be briefly described as follows.

(1) In the multi-beam semiconductor laser chip, the chip parts corresponding to the respective semiconductor laser parts are directly fixed to mutually different leads. For this reason, the heat generated in each semiconductor laser portion is radiated through the lead (supporting plate) that supports each semiconductor laser portion. Therefore, even when one semiconductor laser portion is driven, the other semiconductor laser portion is driven. Thermal crosstalk is less likely to occur, and output characteristics are stable.

[Brief description of drawings]

FIG. 1 is a cross-sectional view of an optoelectronic device that is an embodiment of the present invention.

FIG. 2 is a plan view of the optoelectronic device of this embodiment with a cap removed.

FIG. 3 is a perspective view showing a main part of the optoelectronic device of this embodiment.

[Explanation of symbols]

1 ... Stem, 2-5 ... Lead, 6 ... Glass, 7, 8 ... Support plate, 9 ... Multi-beam semiconductor laser chip, 10, 11 ...
Bonding material, 12, 13 ... Resonator, 15 ... Cap, 16 ...
Isolation groove, 20, 21 ... Semiconductor laser portion,
22 ... Wire, 23, 24 ... Laser light, 25 ... Light receiving element, 26 ... Inclined surface, 27 ... Wire, 30 ... Window, 31 ... Glass plate, 32 ... Bonding material.

Claims (3)

[Claims] 1. An optoelectronic device comprising a multi-beam semiconductor laser chip formed by monolithically forming a plurality of semiconductor laser parts, wherein the multi-beam semiconductor laser chips have mutually different chip parts corresponding to the respective semiconductor laser parts. An optoelectronic device characterized by being fixed to a support plate. 2. The optoelectronic device according to claim 1, wherein the multi-beam semiconductor laser chip is directly fixed to the support plate via a bonding material. 3. The optoelectronic device according to claim 1, wherein the support plate is a lead electrically independent of each other.