JPH0453016Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to the structure of an optical fiber laser diode module used in optical fiber communications.

[Conventional technology] Conventionally, as a technology in this field, "NEC technical report"
Vol.1.38NO.2/1985'', pages 84 to 89. Such a conventional example will be explained based on FIG. 2.

FIG. 2 is a structural diagram showing an example of a conventional optical fiber laser diode module, with the top cover of the case removed and a part of the side surface of the case cut open.

In FIG. 2, 1 is a case, 2 is a laser diode, 3 is a photodiode assembly in which a photodiode is mounted on a photodiode header and wire bonded, 4 is a thermistor for measuring the temperature of the laser diode 2,
5 is a Peltier element for temperature adjustment, 6 is a submount substrate, 7 is a connection pin, 8 is a bonding wire, 9 is an optical fiber, and 10 is an optical fiber support stand.

In the conventional example of such a configuration, the Peltier element 5 is fixed on the bottom surface of the case 1 with low-temperature solder or the like. A submount substrate 6 is fixed to the upper surface of the Peltier element 5 with low-temperature solder or the like.

The submount substrate 6 includes a fiber support 10 for fixing the fiber on which the laser diode 2 is mounted, a photodiode assembly 3 for monitoring the output power of the laser diode 2,
and a thermistor 4 are mounted with solder or the like.

This submount substrate 6 and the above-described elements mounted thereon are wire-bonded to connection pins 7 protruding from the side or bottom surface of the case 1 using bonding wires 8.

Further, the optical fiber 9 is adjusted to have an optimal positional relationship with the laser diode 2 on the fiber support 10, and is fixed with resin or solder.

[Problem that the invention attempts to solve]

However, in such conventional methods, each element or submount board and connection pin are connected by wire bonding after each component is mounted inside the case, so the problem is that the work space is small and bonding work is difficult. Occur.

Moreover, since the Peltier element for temperature adjustment is sensitive to heat, it is not possible to heat it when wire bonding each element or submount board to the connection pin, and wire bonding is not performed to the long protruding connection pin. If this is done, there is a problem in that the application of ultrasonic waves causes the connection pins to vibrate, making it difficult to attach the bonding wire and reducing electrical reliability.

The present invention was made to solve the above problem, and its purpose is to enable electrical connection without wire bonding from each element or submount substrate to connection pins. The object of the present invention is to provide an optical fiber laser diode module that is easy to assemble and has high reliability.

[Means for solving problems]

In order to achieve this objective, the present invention fixes a sub-mound substrate on which an optical fiber and a laser diode are mounted facing each other on a Peltier element provided in a case, and also provides multiple external connection boards in the case. In the optical fiber laser diode module, the optical fiber laser diode module has a structure in which connection pins are provided and the laser diode and photodiode are electrically connected to the corresponding connection pins, wherein each of the connection pins penetrates the bottom surface of the case, and the connection pins are connected to the connection pins. The submount board has a plurality of connection parts each consisting of a notch or a through hole corresponding to each connection pin, and a plurality of wiring patterns formed to form lands for the connection part, and the laser diode is connected to the wiring pattern using bonding wire, and
It is characterized in that it is connected to each wiring pattern and that each wiring pattern is soldered to a connecting pin fitted into a connecting portion.

[Effect]

When assembling the present invention having the above-described structure, first, an optical fiber and a laser diode are mounted on a submount substrate so as to face each other, and this laser diode is connected to a wiring pattern by wire bonding.

After that, the submount board is fixed on the Peltier element provided in the case, and the connection pin penetrated through the bottom of the case is fitted into the connection part of the submount board, and the connection part and the connection pin are connected. The laser diode is electrically connected to the connection pin by soldering.

〔Example〕

An embodiment of the present invention will be described below with reference to FIGS. 1, 3, and 4.

FIG. 1 is a configuration diagram showing an embodiment of an optical fiber laser diode module according to the present invention.
The case is shown with the top cover removed and a portion of the side of the case cut open to reveal the internal structure. FIG. 3 is a perspective view of an example of the submount substrate shown in FIG. 1, and FIG. 4 is a perspective view showing a state in which elements are mounted on the submount substrate of FIG. 3.

In FIG. 1, the submount substrate 11 is
A connecting portion 12 consisting of a notch and a wiring pattern 13 are formed on, for example, a ceramic substrate.

Here, a plurality of connection parts 12 are formed on the side surface of the submount substrate 11 so as to correspond to the connection pins 15 for external connection penetrated through the bottom surface of the case 14, and the wiring pattern 13 is formed on each connection part 12. It is formed to form a land for solder connection.

16 is a laser diode, 17 is a photodiode assembly, and 18 is the laser diode 1.
6 is a thermistor for measuring temperature, 19 is a Peltier element for temperature adjustment, 20 is a bonding wire, 21 is an optical fiber, and 22 is an optical fiber support.

Next, the operation of the above configuration will be explained. First, the laser diode 1 is placed on the submount substrate 11.
6 mounted on the optical fiber support 22, the photodiode assembly 17, and the thermistor 18.
is chip bonded as shown in FIG.

The chip-bonded element is wire-bonded to the wiring pattern 13 of the submount substrate 11 via a bonding wire 20.

Note that since the photodiode assembly 17 is chip-bonded so that this electrode portion overlaps the wiring pattern 13 of the submount substrate 11, there is no need to perform wire bonding.
Therefore, the number of wire bonding operations is reduced compared to the conventional example.

On the other hand, a Peltier element 19 is fixed to the case 14 with low-temperature solder or the like, as shown in FIG.

Thereafter, the submount substrate 11 on which the element is mounted is fixed onto the Peltier element 19 using low-temperature solder having a melting point lower than that of the low-temperature solder, as shown in FIG. At this time, the connection pins 15 of the case 14 are fitted into the connection parts 12 of the submount board 11, and the submount board 11 and the connection pins 15 are connected to each other.
Perform positioning with.

Next, the connection pin 15 is electrically connected to the wiring pattern 13 of the submount substrate 11 by soldering.

This soldering method includes a method using chip solder and a laser soldering device. In this case, if you use a laser soldering device,
Since heating can be performed locally, heat can be prevented from being applied to the Peltier element 19. Further, the type of solder to be used is determined in consideration of the temperature conditions applied to the connection pins 15 when the optical fiber laser diode module is mounted.

After fixing the submount substrate 11 as described above, the laser diode 16 and the optical fiber 21 are aligned in the same manner as in the conventional example. This optical fiber 21 is fixed to an optical fiber support 22 using resin or solder.

In this embodiment, the connecting portion 12 of the submount substrate 11 is a semi-cylindrical notch.
It may also be a through hole. In this case, this through hole is formed at a position corresponding to the connecting pin 12, so that the connecting pin 12 passes through it.

In addition, in this embodiment, the submount substrate 11
Although a case is shown in which the Peltier element 19 is mounted and fixed between the Peltier element 19 and the case 14, it may be directly fixed without using the Peltier element 19, or a support such as a metal block may be mounted instead of the Peltier element 19. The present invention can also be applied to cases where it is fixed.

[Effect of idea]

As explained above, in the present invention, the connecting pins each pass through the bottom of the case, and the submount board has a plurality of connecting parts each consisting of a notch or a through hole corresponding to each connecting pin, and The laser diode on the submount substrate is connected to the wiring pattern using a bonding wire, and each wiring pattern is connected to a connecting pin that fits into the connection part. Since the connection is made by soldering, the following effects can be obtained.

In other words, the wire bonding work is performed before mounting the submount board on the case, so the case and connection pins do not get in the way, improving the bonding work efficiency. Since wire bonding is used, there is no need to be careful about heating temperature.

Furthermore, when fixing the submount board in the case, connecting pins that pass through the bottom of the case are fitted into a plurality of connection parts consisting of notches or through holes provided on the submount board. Therefore, it is possible to easily position the submount substrate and the connection pins.

Moreover, since the submount board and the connection pins are directly soldered, there is no need for wire bonding to the long protruding connection pins.
The reliability of electrical connections is improved, and since the photodiode assembly is chip-bonded in accordance with the wiring pattern of the submount substrate, wire bonding work is reduced.

[Brief explanation of the drawing]

Fig. 1 is a configuration diagram showing one embodiment of the present invention;
3 is a perspective view of the submount substrate shown in FIG. 1, and FIG. 4 is a perspective view of the submount substrate on which elements are mounted. 11...Submount board, 12...Connection part, 13...Wiring pattern, 14...Case, 1
5... Connection pin, 16... Laser diode,
17...Photodiode assembly, 18...
Thermistor, 19... Peltier element, 20... Bonding wire, 21... Optical fiber, 22...
...Optical fiber support.

Claims (1)

[Claims for Utility Model Registration] A sub-mound substrate on which an optical fiber and a laser diode are mounted facing each other is fixed onto a Peltier element provided in a case, and a plurality of external connections are provided in the case. In an optical fiber laser diode module having a structure in which pins are provided and the laser diode and photodiode are electrically connected to corresponding connection pins, each of the connection pins penetrates the bottom surface of the case, and the connection pins are connected to the submount. The substrate has a plurality of connection portions consisting of notches or through holes corresponding to each connection pin, and a plurality of wiring patterns formed to form lands for the connection portions, and connects the laser diode with a bonding wire. 1. An optical fiber laser diode module characterized in that the fiber laser diode module is connected to the wiring patterns by means of a wire, and each wiring pattern is soldered to a connecting pin fitted to a connecting portion.