JPH0543565U - Multi-beam semiconductor laser device - Google Patents

Abstract

(57) [Summary] [Object] An object of the present invention is to provide a multi-beam semiconductor laser device capable of narrowing an optical axis interval of a laser beam. [Structure] Leading electrodes 9, 9 for bonding electrically connected to electrodes 4, 4, 4, 4 respectively formed on a plurality of semiconductor laser element parts 3, 3, 3, 3 constituting a laser chip 1. , 9, 9 are formed via the insulating layer 7,
The wire lines 6, 6, 6, 6 are bonded to the electrodes 9, 9, 9, 9.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a multi-beam semiconductor laser device in which a plurality of semiconductor laser element parts are arranged adjacent to each other.

[0002]

[Prior Art]

 Multi-beam semiconductor laser devices are used in optical heads of magneto-optical disk devices and optical disk devices. Such a multi-beam semiconductor laser device is described, for example, in SANYO TECHNICAL REVIEW VOL.23 NO.1 (1991).

By the way, in the multi-beam semiconductor laser device, a wire line is connected to an electrode of each laser element part in order to apply a current to each laser element part included in the laser device.

FIG. 4 and FIG. 5 are a sectional view and a top view, respectively, showing an outline of a main part of a conventional multi-beam semiconductor laser device.

In the figure, 1 is a laser chip. Element dividing grooves 2, 2, 22 are formed on the upper surface of the chip 1, and laser element portions 3, 3, 3, 3 for outputting laser light are formed respectively. Split electrodes 4, 4, 4, 4 are formed on the upper surfaces of the laser element portions 3, 3, 3, 3 respectively, and a full surface electrode 5 is formed on the lower surface of the laser chip 1 over almost the entire area.

Wire lines 6, 6, 6, 6 are bonded to the divided electrodes 4, 4, 4, 4, respectively.

[0007]

[Problems to be solved by the device]

 By the way, the above-mentioned disk device is required to have a higher recording density, and in order to cope with this, it is necessary to narrow the optical axis interval of the laser beam output from each laser element part in the multi-beam semiconductor laser device. is necessary.

However, in the conventional multi-beam semiconductor laser device, the wire electrodes are connected to the divided electrodes 4, 4, 4, 4 formed on the laser element parts 3, 3, 3, 3 included in the laser chip 1. In order to bond 6, 6, 6, and 6, it is necessary to secure the bonding region by setting the width of the divided electrodes 4, 4, 4, and 4 to about 40 μm, and to reduce the width of each laser element portion to make laser It was difficult to make the optical axis interval of the beam narrower than the conventional value of about 50 μm.

An object of the present invention is to provide a multi-beam semiconductor laser device capable of narrowing the optical axis interval of laser beams.

[0010]

[Means for Solving the Problems]

 The multi-beam semiconductor laser device of the present invention is a multi-beam semiconductor laser device comprising a laser chip in which a plurality of semiconductor laser element parts are arranged adjacent to each other, and each first electrode formed on each element part, An insulating layer formed on the first electrode, and second electrodes electrically connected to the first electrodes through connection windows provided in the insulating layers on the first electrodes, respectively. Is characterized by. In particular, the second electrode is characterized in that it is formed even on the laser chip where the laser element portion is not formed.

[0011]

[Action]

 As described above, when each second electrode electrically connected to each first electrode formed on each element portion is formed through the insulating layer, a wire line can be bonded at the second electrode, The width of one electrode, that is, the width of the element portion can be narrowed, and the optical axis interval of the laser beam can be narrowed.

Further, when the second electrode is formed even on the laser chip on which the laser element portion is not formed, the wire line can be bonded by the second electrode on the laser chip on which the element portion is not formed. Do not damage the parts.

[0013]

【Example】

 A 4-beam semiconductor laser device will be described as an embodiment of the present invention. 1 and 2 are a sectional view and a top view showing the outline of the multi-beam semiconductor laser device of this embodiment, respectively.

In the figure, reference numeral 1 denotes a laser chip, and element cutting grooves 2, 2 and 2 each having a width of 2 to 5 μm and a depth of 5 to 10 μm are formed on the upper surface of the laser chip 1, respectively, and laser light is emitted. For example, the laser element portions 3, 3, 3, 3 having a width of 10 to 15 μm to be output are arranged adjacent to each other. In this laser element section, for example, a predetermined active layer, cladding layer, block layer, etc. are formed on a GaAs substrate by liquid phase epitaxy, etching, etc., and this block layer blocks light in the direction parallel to the active layer. Is configured to do.

On the upper surfaces of the semiconductor laser element parts 3, 3, 3, 3, for example, dividing electrodes (first electrodes) 4, 4, made of Au / Sn, having a width of about 5 to 15 μm and a thickness of about 0.5 μm are provided. 4 and 4 are formed so as to be electrically connected to the laser element portions 3, 3, 3 and 3, respectively. An insulating layer 7 made of a polyimide film and having a thickness of about 2.5 μm is formed on the upper surfaces of the semiconductor laser element portions 3, 3, 3, 3 including the dividing electrodes 4, 4, 4, 4. 7 has no insulating layer formed on a part of each of the dividing electrodes 4, 4, 4, and 4, for example, the connection windows 8, 8, 8, 8 having a width of about 5 to 15 μm and a length of about 50 μm are chemically etched. It has been created by the company.

9, 9, 9, and 9 are formed by, for example, vapor deposition and patterning, and are, for example, 1-1. This is a lead electrode (second electrode) having a thickness of 5 μm. The extraction electrodes 9, 9, 9, 9 are connected to the respective dividing electrodes 4, 4, 4, 4 at the respective connection windows 8, 8, 8, 8 respectively, and the dividing electrodes in a state where the insulating layer 7 is interposed therebetween. 4, 4, 4, 4, that is, up to the end portion of the laser chip 1 where the laser element portions 3, 3, 3, 3 for outputting light are not formed. The lead-out electrodes 9, 9, 9, 9 have a width such that a wire line can be bonded, for example, a width of 60 μm, and the wire line 6, 6, 6, 6 made of gold or the like is bonded at each end thereof. ing. A full surface electrode 5 made of gold or the like is formed on almost the entire lower surface of the laser chip 1.

The electrode structure of such a semiconductor laser device has an end portion of a laser chip in which a laser element portion is not formed in a state where each extraction electrode connected to each dividing electrode has an insulating layer interposed therebetween. Is formed, and a wire is bonded to the extraction electrode on the end of the laser chip, and the connection between the dividing electrode and the extraction electrode may be small. Can be narrowed to narrow the interval between the optical axes of the laser beams to about 10 μm. Further, since the laser element portion is not formed at the end portion of the laser chip for bonding the wire wire, the photoactive layer or the like in the portion which outputs the light will not be damaged by the bonding.

The location of the lead-out electrodes is not limited to the above-mentioned embodiment, and all four lead-out electrodes may be formed at one end of the laser chip, and can be appropriately changed. Further, the lead-out electrode may be wide so that only the portion for bonding the wire line has the size of the bonding region. A conductive wire such as a wire wire may be connected to the extraction electrode by a method other than bonding.

Further, as shown in FIG. 3, the extraction electrodes 9, 9, 9, 9 may be formed only on the laser element portions 3, 3, 3, 3. However, in this case, the width of the laser chip can be narrowed, but as in the above embodiment, the extraction electrode is formed up to the end of the laser chip where the laser element is not formed, and the wire line is bonded to this end. It is more preferable that the active layer, the cladding layer and the like continuing from the laser element portion are not provided at the end of the laser chip.

Further, the present invention is not limited to the above-mentioned embodiments, and, for example, the semiconductor laser device may be made of a structure, material, etc. other than the above-mentioned embodiments. Further, the material of the electrode needs to be changed appropriately depending on the material of the laser element. Further, the insulating layer is not limited to the above polyimide, and various insulating materials such as SiO ₂ and Al ₂ O ₃ can be used.

[0021]

[Effect of the device]

 In the multi-beam semiconductor laser device of the present invention, each second electrode electrically connected to each first electrode formed on each element portion is formed through an insulating layer, and a wire wire is formed at the second electrode. Since the bonding can be performed, the width of the element portion, that is, the width of the first electrode can be narrowed, and the optical axis interval of the laser beam can be narrowed.

When the second electrode is formed even on the laser chip on which the element portion is not formed, the wire line can be bonded by the second electrode on the laser chip on which the element portion is not formed, and the element portion can be bonded. Does not damage

[Brief description of drawings]

FIG. 1 is a sectional view showing an outline of a main part of a multi-beam semiconductor laser device according to an embodiment of the present invention.

FIG. 2 is a top view of the multi-beam semiconductor laser device of the above embodiment.

FIG. 3 is a top view showing an outline of a main part of a multi-beam semiconductor laser device according to another embodiment of the present invention.

FIG. 4 is a sectional view showing an outline of a main part of a conventional multi-beam semiconductor laser device.

FIG. 5 is a top view of the conventional multi-beam semiconductor laser device.

[Explanation of symbols]

 1 Laser Chip 3 Semiconductor Laser Element Section 4 First Electrode 6 Wire Wire 7 Insulating Layer 9 Second Electrode

Claims (2)

[Scope of utility model registration request] 1. A multi-beam semiconductor laser device comprising a laser chip in which a plurality of semiconductor laser element portions are arranged adjacent to each other, each first electrode formed on each element portion, and on the first electrode. A multi-beam having a formed insulating layer and second electrodes electrically connected to the first electrodes through connection windows provided in the insulating layers on the first electrodes, respectively. Semiconductor laser device. 2. The multi-beam semiconductor laser device according to claim 1, wherein the second electrode is formed even on a laser chip where a laser element portion is not formed.