JPS63200590A - Semiconductor laser device - Google Patents

Abstract

PURPOSE:To reduce the size and the number of steps, to shorten wirings and to enhance the frequency of a semiconductor laser device by bonding a semiconductor laser chip on a semiconductor integrated circuit, thereby eliminating a silicon submount. CONSTITUTION:A semiconductor laser bonding part 7 is formed on an electronic circuit chip 3, and tin is deposited only on a part equal to the chip area of a semiconductor laser 1. An integrated photodetector 8 is formed on the chip 3, and the photodetector 8 of relatively large area is provided at the rear of the part 7. Accordingly, the outgoing beam of the laser 1 rearward is photodetected to obtain a monitoring output.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a semiconductor laser device used in optical information processing and optical communications such as optical disk systems.

2. Description of the Related Art In recent years, semiconductor lasers have attracted attention as light sources for optical communication and optical information processing due to their characteristics such as small size, high efficiency, and ease of direct modulation, and are being used in a wide range of fields. Nowadays, with the aim of making devices that use semiconductor lasers smaller and increasing the frequency of signals handled, studies are being conducted to integrate electronic circuits and semiconductor lasers into opto-electrical integrated circuits. There is. These studies include a method of monolithically integrating the semiconductor laser and the electronic circuit, and a method of fabricating the semiconductor laser and the electronic circuit separately and integrating them in a single package in a non-integrated manner. Although the monolithic integration method allows for easy miniaturization and high frequency, it requires the same semiconductor material as the semiconductor laser that makes up the electronic circuit, and the manufacturing process becomes complicated, making it difficult to create. There are disadvantages that it takes a long time and the yield decreases. Furthermore, the hybrid integration method has certain limitations in terms of miniaturization and high frequency, and the internal structure of the package becomes complicated.

A conventional semiconductor laser device as described above will be described below with reference to the drawings.

FIG. 2 is a perspective view of a conventional semiconductor laser device in which a semiconductor laser and an electronic circuit are integrated in a hybrid manner. In FIG. 2, 1 is a semiconductor laser, 2 is a silicon submount, 3 is an electronic circuit chip, 4 is a PIN photodiode, 5 is a heat sink, and 6 is a stem. The operation of the conventional semiconductor laser device configured as described above will be described below. The processed or generated signals in the electronic circuit chip 3 are applied to the semiconductor laser 1 .

The semiconductor laser 1 emits light according to this signal or a signal directly applied from the outside. The light from the front facet of the semiconductor laser 1 is used as a signal, and the light from the rear facet is used as a PI signal.
The light is received by an N photodiode and used as a monitor of light output. The silicon submount 2 is used for the purpose of alleviating the difference in thermal expansion coefficient between the semiconductor laser 1 and the heat sink 5 and facilitating the assembly process.

Problems to be Solved by the Invention However, with the above configuration, not only does the number of assembly steps increase, but also a large space is required on the heat sink 5, which limits miniaturization. The wires connecting 3 cannot be shortened below a certain level, and there is a limit to how high the frequency can be increased. SUMMARY OF THE INVENTION In view of the above drawbacks, the present invention provides a semiconductor laser device that has a hybrid configuration but can be made as compact as a monolithic configuration, has a high frequency, and simplifies the assembly process.

Means for Solving the Problems In order to solve the above-mentioned problems, the semiconductor laser device of the present invention is provided by bonding a semiconductor laser onto a space provided on a semiconductor chip in which an electronic circuit is integrated. It is constructed by bonding it directly to the heat sink.

Operation This configuration eliminates the need for a silicon submount since the electronic circuit chip serves as the silicon submount. Therefore, the size can be reduced and the number of man-hours can be reduced. Furthermore, since the electronic circuit chip and the semiconductor laser are located close to each other, the wiring can be shortened and it is easy to increase the frequency.

Example Hereinafter, an embodiment of the present invention will be explained with reference to the drawings. Let me explain from the start.

FIG. 1 is a perspective view showing the structure of a semiconductor laser device according to an embodiment of the present invention.

In FIG. 1, 7 is a semiconductor laser bonding section configured on the electronic circuit chip 3;
Tin is deposited to a thickness of approximately 1 μm only on this portion, which is equal to the chip area.

Reference numeral 8 denotes an integrated light receiving element, which is also constructed on the electronic circuit chip 3. The operation of the semiconductor laser device configured in this way will be explained.

Since the semiconductor laser tip 1 is bonded onto the semiconductor laser bonding part on the electronic circuit chip 3, wiring can be done with extremely short lines. Further, on the electronic circuit chip 3, immediately behind the semiconductor laser bonding section, an integrated light receiving element 8 having a relatively large area is provided. Therefore, the light emitted backward from the semiconductor laser 1 is received by this integrated light receiving element, and a monitor output can be obtained.

As a result, not only silicon submount 2 but also P
The IN photodiode 4 can also be omitted, and the assembly process can be simplified.

Moreover, electronic circuits having various functions can be integrated into the electronic circuit chip 3. Examples include a constant light output drive circuit for a semiconductor laser, a pulse drive circuit, and a high frequency superimposition circuit for reducing emission intensity noise of a semiconductor laser.

Further, there is no particular restriction on the semiconductor material constituting the electronic circuit chip 3, and any material may be used as long as a good electronic circuit can be constructed. However, when the material is the same as that of the semiconductor laser, the stress due to the difference in thermal expansion coefficients applied to the semiconductor laser can be minimized.

Effects of the Invention As described above, the present invention provides a hybrid opto-electronic integrated circuit that can be made as compact and as high-frequency as monolithic opto-electronic integrated circuits without reducing the yield. It can be done, and its practical effects are great.

[Brief explanation of the drawing]

FIG. 1 is a perspective view of the structure of a semiconductor laser device according to an embodiment of the present invention, and FIG. 2 is a perspective view of the structure of a conventional hybrid 7/RAD optical-electrical integrated circuit. 1... Semiconductor laser, 2... Silicon submount, 3... Electronic circuit chip, 4...
- PIN photodiode, 5... heat sink, 6... stem, 7... semiconductor laser bonding section, 8... integrated light receiving element. Name of agent: Patent attorney Toshio Nakao and 1 other person5-
--e-Tosonk C-su y4

Claims (2)

[Claims] (1) A semiconductor laser device characterized in that a semiconductor laser chip is bonded onto a semiconductor integrated circuit. (2) The semiconductor laser device according to claim 1, wherein the semiconductor integrated circuit includes a light receiving element.