JPH01192185A - Wiring structure of integrated bistable semiconductor laser - Google Patents

Abstract

PURPOSE:To prevent a cross talk and miniaturize a device by a method wherein two or more bistable semiconductor lasers are structured into one piece such as to have their electrodes positioned on the same plane, and the electrodes and the wiring electrodes are electrically and mechanically connected with each other. CONSTITUTION:Two or more bistable semiconductor lasers 1 are structured into one piece such as to make their electrodes 2 positioned on the same plane, a substrate 4 provided with wiring electrodes 3 which are situated at the position corresponding to the electrodes 2 is made to face toward the bistable semiconductor laser 1, and the electrodes 2 and the wiring electrodes 3 are electrically and mechanically connected with each other through a flip chip bonding. The reason that electrodes of a bistable semiconductor lasers are arranged on the same plane is that a monolithic structure can be easily attained with the directions in which laser rays are inputted or outputted or the directions of the active layers being in parallel with each other. By these processes, for instance, the processing of optical signals in parallel is made possible in a time division light exchange system. And, as electrodes are positioned on the same plane, the flip chip bonding of the electrodes with the wiring electrodes of a substrate can be facilitated.

Description

[Detailed Description of the Invention] Regarding the wiring structure of an integrated bistable semiconductor laser, for the purpose of reducing the O-stalk of each bistable semiconductor laser and downsizing the device, a plurality of bistable semiconductor lasers are interconnected with their electrodes. They are integrated so that they are located on the same plane, and placed at positions corresponding to the above electrodes.
111! A substrate having a pole is opposed to the bi-bun strained semiconductor laser, and the electrode and the wiring electrode are electrically and mechanically connected by flip-chip bonding.

Industrial applications.

The present invention relates to a wiring structure for an integrated bistable semiconductor laser.

In recent years, in fields such as communications and information processing, research has been active in optical switching systems and optical signal processing systems that directly process optical signals without converting them into electrical signals due to demands for faster processing speeds. It has become

One of the devices required to implement these methods is an optical memory for storing optical signals.

A bistable semiconductor laser is an optical device that can be used as an optical memory, and optimization of the wiring structure is being sought for its practical use.

Figure 5 is an explanatory diagram of a conventional bistable semiconductor laser.
be. This bistable semiconductor laser 41 has an active layer 4'
, 2 longitudinally divided electrodes 43, 44, and a common ground electrode 45 is provided on the back side thereof. By controlling the current value supplied to the divided electrodes 43, 44, bistability of the electrical or optical signal is created.

FIG. 6 shows that in the above-mentioned bistable semiconductor laser, the output light intensity P and the current value I flowing into the electrode 44 when the current UT 11 flowing into the electrode 43 are constant at appropriate values, or 1.12, are appropriate values. Input light intensity P when constant
It is a graph showing the relationship with IN.

In this way, (i) the output light intensity P increases or decreases as PIN increases or decreases within an appropriate range; Since hysteresis occurs in changes of , 1, this can be stored for the input electrical signal or input optical signal.

Applications of the memory function for the input optical signal of the bistable semiconductor laser shown in FIG. 5 can be found, for example, in time-division optical switching systems. That is, by placing N semiconductor lasers in parallel between the IXN optical switch and the NXI optical switch and controlling them sequentially, the time-division multiplexed signal of one channel can be transferred to another channel. It can move on the time axis and achieves a light exchange function. In such applications, it is necessary to arrange a plurality of bistable semiconductor lasers in parallel, so for example, as shown in FIG. 7, each semiconductor laser 41 (
It may be proposed to integrate two active layers (three in the figure) so that these active layers are parallel to each other.

Problem to be Solved by the Invention However, when considering a wiring structure using normal wire bonding in the integrated structure shown in FIG. However, a problem arises in that crosstalk between elements increases. Since this crosstalk is caused by an electromagnetic phenomenon caused by the inductance component of the bonding wire 51, it becomes more prominent as the signal processing speed increases, and goes against the high speed performance of optical devices. On the other hand, to avoid this crosstalk,
Although it would be possible to devise a wire wiring structure so that the bonding wires 51 do not come close to each other, this poses a problem of increasing the size of the device.

The present invention was created in view of these technical problems, and aims to provide a wiring structure for integrated bistable semiconductor lasers that can reduce crosstalk between individual bistable semiconductor lasers and miniaturize the device. The purpose is

Means to solve problems FIG. 1 is a diagram showing the principle of the present invention.

The wiring structure of this integrated bistable semiconductor laser is such that a plurality of bistable semiconductor lasers 1 are integrated so that their electrodes 2 are located on the same plane, and a substrate has wiring electrodes 3 at positions corresponding to the electrodes 2. 4 is opposed to the bistable semiconductor laser 1, and the electrode 2 and the wiring electrode 3 are electrically and mechanically connected by flip-chip bonding.

Function: In the present invention, the electrodes of the bistable semiconductor laser are located on the same plane, which facilitates the integration of the structure with the light input/output direction, that is, the direction of the active layer, parallel to each other. This is to do so. This enables parallel processing of optical signals in, for example, a time-division optical switching system. Furthermore, by locating the electrodes on the same surface, flip-chip bonding with the wiring electrodes of the substrate can be facilitated.

As described above, the present invention eliminates the need for conventional wiring using wire bonding, thereby preventing crosstalk and making it possible to downsize the device.

Example Examples of the present invention will be described below based on the drawings.

FIG. 2 is a perspective view of an integrated bistable semiconductor laser that may be used in the practice of the present invention. 11 is a bistable semiconductor laser having electrodes 14 and 15 on its upper surface and an active layer 16 inside; 12 is a bistable semiconductor laser having electrodes 17 and 18 on its upper surface and an active layer 19 inside; 13 is a bistable semiconductor laser having electrodes 17 and 18 on its upper surface and an active layer 19 inside; It is a bistable semiconductor laser having an electrode 20.21 on its upper surface and an active layer 1122 inside, and these bistable semiconductor lasers 11, 12.13 are integrally joined.

This integrated structure can also be obtained by conventional semiconductor integration technology. 23 is a common ground electrode provided on the opposite side to the above electrodes.

FIG. 3 is a plan view of a substrate that can be used to implement the present invention, and when this substrate 31 faces the top side of the integrated bistable semiconductor laser shown in FIG. .18. Wiring electrodes 3 at positions facing each of the two
3, 34.35, and electrodes 14.17.
A common wiring electrode 32 is provided at a position opposite to the wiring electrode 20. Note that the portions indicated by dotted lines in FIG. 3 are the planned connection positions between each wiring electrode and the upper surface of the integrated bistable semiconductor laser by electrode stopper flip-chip bonding.

FIG. 4 shows a cross-sectional configuration along rV-■ in FIG. 3 when the integrated bistable semiconductor laser shown in FIG. 2 and the substrate 31 shown in FIG. 3 are wired facing each other. It shows. 41 is a solder bump made of ALI-Qe gold alloy, for example, and electrically and mechanically connects the electrode 20 on the laser side and the wiring electrode 32 on the substrate side. 42
Similarly, solder bumps electrically and mechanically connect the electrode 21 on the laser side and the wiring electrode 35 on the substrate side.

When blip chip bonding is performed using solder bumps in this way, there is little electromagnetic influence between the electrically connected parts, so the individual bistable semiconductor lasers 11
, 12, 13 is prevented. Further, since electrical and mechanical connections are achieved in extremely small parts, it is possible to downsize the device.

As described in detail above, the present invention has the effect of preventing O-stalk between individual bistable semiconductor lasers and making it possible to miniaturize the device.

In this way, the present invention greatly contributes to the high speed required for optical signal processing and the compactness required for optical devices. Furthermore, a general effect of performing flip chip bonding is that wiring work is facilitated.

[Brief explanation of the drawing]

FIG. 1 is a diagram of the principle of the present invention, FIG. 2 is a perspective view of an integrated bistable military conductor laser that can be used to implement the present invention, and FIG. 3 is a diagram of a substrate that can be used to implement the present invention. A plan view, FIG. 4 is a cross-sectional configuration diagram when the integrated bistable semiconductor laser shown in FIG. 2 and the substrate shown in FIG. 3 are wired facing each other, and FIG. 5 is a conventional bistable semiconductor laser. In order to explain one configuration example, FIG. 6 is an explanatory diagram of the operating characteristics of the bistable semiconductor laser shown in FIG. 5, and FIG. 7 is an explanatory diagram of the wiring structure of a conventional integrated bistable semiconductor laser. be. 1.11.12.13... Bistable semiconductor laser, 2.
14.15.17゜18.20.21... Electrode, 3.32, 33.34.35... Wiring electrode, 4.31
... Board, 41.42 ... Solder bump. Honkomyo
Fig. 3 Fig. 13: Original r9 constant〕Rarai-'su' 31:, i o-reverse, 41.42: Half a day IY-7゜f change from A-column Fig. 5 It, l2fJn Hikino PIN Promotion rice A row Figure 6 f Anami Song A row Figure 7

Claims (1)

[Claims] A plurality of bistable semiconductor lasers (1) are integrated so that their electrodes (2) are located on the same plane, and a wiring electrode (3) is provided at a position corresponding to the electrode (2). A substrate (4) having a substrate (4) is placed opposite the bistable semiconductor laser (1), and the electrode (2) and the wiring electrode (3) are electrically and mechanically connected by flip-chip bonding. Features the wiring structure of an integrated bistable semiconductor laser.