JPS62276892A - Electronic component - Google Patents

Abstract

PURPOSE:To obtain favorable thermal diffusivity and achieve stable optical communications by constructing a pedestal from a material, the thermal expansivity of which is very close to that of lower electrode plate made of peltier element. CONSTITUTION:A pedestal 9 that is held between a peltier element 10 and the bottom of package 7 is constructed from copper tungsten having high thermal conductivity as well as thermal expansivity which is very close to that of electrode plates 27 made of alumina ceramic of peltier element 10 and the peltier element 10 is fixed with solder having the low melting point. This configuration prevents soldering 47, with which the pedestal 9 the peltier element 10 are connected, from being subject to fatigue failure and not only improves reliability for junction and thermal conductivity but also achieves favorable thermal diffusivity and stable optical communications.

Description

Detailed Description of the Invention 3. Detailed Description of the Invention [Field of Industrial Application] The present invention relates to an electronic component in which a Peltier element is fixed on the bottom of a package via a pedestal, and particularly to an electronic component having a Peltier element fixed on the pedestal. The present invention relates to an electronic component having a subcarrier on which a laser diode chip is mounted.

[Prior Art] A semiconductor laser device is used as one of the light sources for optical communication. Regarding this optical communication laser module (semiconductor laser device), for example, 71-page publication JVo1.
38, No. 2/1985, P84-P89.

This document describes a laser element that emits laser light, and a Ge
-PD (light receiving element), thermistor that monitors the temperature of the laser element, Tala (Peltier element) for temperature adjustment
are built into each package, and an optical fiber is provided to guide the laser beam to the outside of the puff cage. The low temperature side of the Peltier element is fixed to the heat sink by solder. Also, the leads that serve as external terminals are of a dual in-line type. As one of the dual in-line lead structures described above, a structure in which the leads are attached through insulating glass to the bottom of the package is described.

[Problem that the invention seeks to solve]

As described in the above-mentioned document, one structure in which the leads are of a dual in-line type is a structure in which the leads are arranged in two rows at the bottom of the package. In this case, glass is used to insulatively fix the leads to the conductive puff cage, and the metal and glass that make up the package are selected from materials that have approximately the same coefficient of thermal expansion. is used and is commonly used to package Fe
-Ni -Co (Kovar), and
The lead is fixed with borosilicate glass (Kovar glass).

The present inventor studied a technique for enhancing the heat dissipation effect of the Peltier element. Although the following is not a publicly known technique, it is a technique studied by the present inventor, and its outline is as follows.

That is, in the case where the package has leads passing through it and is insulatively supported, the puff cage bottom plate must be made of Kovar as described above. However, since Kovar has a low thermal conductivity of 0.04 cal/cm-sec·0c, the heat dissipation of the Peltier element cannot be said to be good. Therefore, faster aging on the high temperature side of the Peltier element
In order to achieve this, a pedestal made of a copper plate with good thermal conductivity was interposed between the Peltier element and the bottom of the package.

This structure improves heat dissipation due to improved thermal conductivity from the bottom of the package, so it can effectively cool the laser diode chip mounted on the top of the Peltier element.

However, since the electrode plate of the Peltier element is made of alumina ceramic, when a thermal cycle test is performed, thermal stress is repeatedly generated between the electrode plate and the copper plate, which has a large coefficient of thermal expansion, and the solder that fixes the alumina ceramic plate and the copper plate The inventor has revealed that this causes fatigue failure.

An object of the present invention is to provide an electronic component with good heat dissipation.

Another object of the present invention is to provide an electronic component with a highly reliable structure in which fatigue failure of the solder that fixes the Peltier element to the pedestal is less likely to occur.

The above and other objects and novel features of the present invention include:
It will become clear from the description of this specification and the accompanying drawings.

Means for Solving Problem C] A brief summary of typical inventions disclosed in this application is as follows.

That is, in the optoelectronic device for optical communication of the present invention, the pedestal interposed between the Peltier element and the bottom of the package has a coefficient of thermal expansion similar to that of the electrode plate made of alumina ceramic of the Peltier element, and It is made of copper tungsten, which has high thermal conductivity, and the Peltier element is fixed with low melting point solder.

[Effect]

According to the above means, in the optoelectronic device for optical communication, the pedestal interposed between the Peltier element and the bottom of the package has a coefficient of thermal expansion similar to that of the electrode plate made of alumina ceramic of the Peltier element. And since it is made of copper tungsten, which has high thermal conductivity, the solder that connects the pedestal and Peltier element is less likely to suffer from fatigue failure, increasing the reliability of the bond and providing good thermal conductivity. Heat dissipation is also stable, and stable optical communication can be achieved.

[Embodiment] An embodiment of the present invention will be described below with reference to the drawings.

Here, the drawings will be briefly explained. FIG. 1 is an enlarged sectional view showing a state in which a Peltier element in a photoelectronic device according to an embodiment of the present invention is fixed to a pedestal via solder;
The figure is a perspective view showing the main parts of the optoelectronic device, FIG. 3 is a plan view with the package lid removed, FIG. 4 is a sectional view of the optoelectronic device, and FIG. 5 is a perspective view showing the package body. , FIG. 6 is a perspective view of the subcarrier, FIG. 7 is a plan view of the heat sink in the subcarrier, FIG. 8 is a sectional view of the solder ring at the inner end of the positioning fixture, and FIG. 9 is the same. FIG. 10 is a perspective view showing the state in which the laser diode chip is mounted on the subcarrier, and FIG. 10 is a schematic diagram showing the state in which the optical fiber is fixed.

In this example, the wavelength is 1.3 μm or 1°5 μm.
An example in which the present invention is applied to an optoelectronic device as a transmitting device in optical communication that includes a built-in laser diode chip that emits laser light will be described.

Here, the structure of the optoelectronic device of the present invention will be explained.

In the optoelectronic device, as shown in FIGS. 2 to 4, a package 1 is box-shaped and has a flange 3 provided with a mounting hole 2 for mounting the package 1 at one end of the package 1. It has a fiber support 4 at the other end and is structured to guide an optical fiber cable 5.

This optoelectronic device has two rows of leads 6 protruding from the bottom of the package 1, forming a dual in-line structure. The package 1 consists of a box-shaped package body 7 having a flange 3 at one end and an open top, and a puff cage lid 8 that tightly covers the opening of the package body 7.

Further, a pedestal 9 is fixed on the bottom of the package body 7, and a Peltier device IO is mounted on this pedestal 9.
is fixed, and a subcarrier 11 is fixed on this Peltier element 10. This subcarrier 11 has a heat sink 14 having a mounting portion 12 and a protruding portion 13 on its main surface as a pedestal member, and a laser diode chip 15 . A cylindrical positioning fixture 17 that guides the optical fiber 16 that takes in the laser light emitted from the laser diode chip 15 from its tip (inner end). A light receiving element that monitors the laser beam! 8. a thermistor 19 for monitoring the temperature of the heat sink 13;
are each fixed. The part of the optical fiber cable 5 inside the package 1 has its jacket removed and becomes an optical fiber 16 consisting of a core and a craft covering the core. diode chip 15
The light emitting surface is faced to one side. Furthermore, the electrodes of each element and predetermined leads 6 are electrically connected by conductive wires 20. Note that this optoelectronic device does not contain resin or soldering flux in its package, and care has been taken to prevent characteristic deterioration due to these resins.

Such a photoelectronic device performs optical communication by emitting laser light from the laser diode chip 15 and transmitting the emitted laser light to a desired location via the optical fiber cable 5.

At this time, this optoelectronic device monitors the laser beam with the light receiving element 18, and based on this information, the laser diode
The output of the knob 15 is controlled to perform stable optical communication. In addition, this optoelectronic device monitors the temperature of the heat sink 14 with the thermistor 19, controls the Peltier element 10 based on this information, and constantly controls the laser diode chip 15.
The system is designed to operate within a certain temperature range to stabilize optical communications.

Here, before explaining each structural part of the optoelectronic device, the part related to the present invention, that is, the pedestal 9 interposed between the subcarrier 11 and the bottom of the package will be explained.

As shown in FIG. 1, since the pedestal 9 has a Peltier element 10 fixed thereon via solder 47, it is desired that the pedestal 9 has good thermal conductivity for heat dissipation. The upper and lower electrode plates 27 of 10 have a coefficient of thermal expansion of 6.
It is made of alumina ceramic of about 7X10-b/'c. The pedestal 9 has a thermal expansion coefficient of 1.
If copper or the like having a good thermal conductivity of 7.0 x 10-''/'c is used, the solder 47 that joins the pedestal 9 and the electrode plate 27 will suffer fatigue failure due to temperature cycling.To avoid this, The pedestal 9 has a thermal expansion coefficient of, for example, 6.
0-7. Qxl 0-b/'c, thermal conductivity is 0.5~
The pedestal 9 is made of copper tungsten (CuW) with a temperature of 0.67 cal/cm = sec-''c.The pedestal 9 has a larger area than the electrode plate 27, and heat is applied to the bottom surface of the package body 7, which has a larger area. It is designed to convey.

Further, the Peltier element 10 is usually assembled with solder having a low melting point of about 130'C. Therefore, if the melting point of the solder 47 is high, assembly of the Peltier element 10 will be impaired when the Peltier element 10 is fixed to the pedestal 9. Therefore, the solder 47 is made of InSn having a melting point of about 120°C.
Solder consisting of is used. Further, the pedestal 9 is fixed to the bottom of the package body 7 by a flankless connection, that is, by brazing.

By using such a pedestal 9, the heat on the high temperature side of the Peltier element 10 is transferred to the bottom plate surface of the package body 7, which has a wider area than the electrode plate 27 of the Peltier element 10. Since heat is efficiently transferred to the Peltier element 10, the cooling effect by the Peltier element 10 increases and the heat dissipation effect becomes stable.

This optoelectronic device consists of iron-nickel-cobalt (FeNi)
It is composed of individual parts such as a flat package lid 8 made of Kovar (-Co) alloy, an optical fiber cable 5, and a Peltier element 10, and several subassembly parts.

Next, each part of such a photoelectronic device will be explained.

As shown in FIG. 5, the buff cage main body sub-assembly parts including the main component of the puff cage main body 7 are the package main body 7. Flange 3. Fiber support 4. It consists of 6 leads and 9 pedestals.

The package body 7 has a structure in which a flange 3 having a mounting hole 2 is attached to one end thereof. Further, as shown in FIG. 3, seven leads 6 are arranged in two rows at the bottom of the package body 7. Each lead 6 passes through the bottom plate of the package body 7 and is insulatively fixed to the package body 7 by an insulating support 21 made of Kovar glass, which has substantially the same coefficient of thermal expansion as Kovar constituting the bottom plate. These glued 6 are
For example, as shown in FIGS. 2 and 3, the left end glue 6 of the front and rear lead rows becomes the external terminal of the light receiving element 18, and the second wood from the left of the front lead row The three-way glue 6 becomes the external terminal of the laser diode chimney 15, and the fourth and fifth wood-grained glue 6 from the left in the lead row on the front side become the external terminals of the thermistor 19. In addition, the right end glue 6 of the front and rear lead rows is connected to a Peltier element 10, respectively.
This serves as an external terminal. The other slot 0'6 becomes an empty lead that is not used in this embodiment.

The wire 20 connected to the Peltier element IO is connected to the lead 6 by welding without using resin or flux, but the other wires 20 are connected to the lead 6 by ultrasonic wave.
Connected by earbonding. Ultrasonic wire bonding uses ultrasonic vibration to perform wire bonding, so wire 2 is attached to the top end of long lead 6 as shown in the figure.
If 0 is connected, the lead 6 will vibrate and bonding cannot be performed reliably. Therefore, in this embodiment, the leads 6 to which the wires 20 are connected by ultrasonic wire bonding are as shown in FIGS. 2, 3, and 5.
They are connected by a reinforcing plate 22 to prevent the leads 6 from vibrating during ultrasonic wire bonding.

Further, the reinforcing plate 22 also plays the role of stabilizing the use of the optoelectronic device in a high frequency range by adopting the following structure. That is, the reinforcing plate 22 is made of an insulating ceramic plate, and is in contact with the lead 6.
The casting surfaces are partially meklyzed.

Since this metallized layer is provided to have a constant width along the lead 6, the area through which the current flows in the lead 6 is increased, and the parasitic inductance is reduced.
It is now possible to stably perform optical communications in a high frequency range of up to 565 Mbit.

The package body subassembly part has a fiber support 4 attached to the end face of the package body 7 opposite to the flange 3. The fiber support 4 includes an outer support 25 each formed of a cylindrical body, and an inner support 26 fitted into the inner end of the outer support 25.

The outer support 25 has its inner end penetrated and hermetically soldered to the end of the package body 7.

Further, the outer end portion of the outer support body 25 has a thin-walled tube structure and is easily crushed by caulking.

Further, the inner support 26 has a structure in which the outer end is fitted into the inner end of the outer support 25, and the inner end extends thinly and has an inclined surface at the tip. Further, a ring-shaped solder 30 is provided on this inclined surface portion.

In such a fiber support 4, before the optical fiber cable 5 is inserted into the fiber support 4,
The jacket is removed over a certain length on the tip side, and the portion of the optical fiber 16 from which the jacket has been removed extends over the entire area of the inner support 26 and the outer support 2.
5, and the jacketed portion extends to the outer end portion of the outer support 25.

The package body subassembly part has a pedestal 9 fixed on its bottom. This pedestal 9 is fixed to the bottom surface of the package body 7 on the side of the flange 3 by brazing. Since the electrode plates 27 above and below the Peltier element 10 are made of alumina ceramic having a thermal expansion coefficient of approximately 6.7 x 10-6/'c, this pedestal 9 has a thermal expansion coefficient of 6.7 x 10-6/'c. .0~? , 0XIO-6/'c. Moreover, this CuW has a thermal conductivity of 0. 5~0°67c
The heat dissipation property of the Peltier element 10 is increased by a high value of al/cm-sec-'c.

Further, one end of the pedestal 9 contacts the peripheral wall of the package body 7 on the flange 3 side, so that heat is transmitted from the pedestal 9 to the flange 3 via the peripheral wall.

Note that the thermal expansion coefficient of Kovar forming the bottom of the package body 7 is 5.3xlO-6/'c. Furthermore, other materials that can be used as the pedestal 9 include SiC and the like.

The subcarrier 11 as a subassembly part is the sixth
The structure is as shown in the figure.

As shown in FIG. 6, this subcarrier 11 has a heat sink 14 made of a rectangular plate as its main component. The heat sink 14 has a mounting portion 12 and a support portion 13 on its main surface. These mounting portion 12 and support portion 13 have a protruding shape. The mounting portion 12 is arranged to cross the central region of the main surface of the heat sink I4, and the support portion 13 extends parallel to the mounting portion 12 on one end side. In addition, these mounting portions 12 and supporting portions 1
3 extends in a direction perpendicular to an inclined axis that is inclined at θ with respect to the center line of the heat sink 14 .

Further, a cylindrical positioning fixing member I7 is fixedly fixed to the support portion 13 through the support portion 13. This positioning fixing body 17 serves as a support shaft that guides the optical fiber 16, and also serves as an adjustable shaft that can adjust the position of the tip of the optical fiber 16. For this reason, the positioning fixing body 17 is made of a material that is easily plastically deformed, for example, cupronickel, and as shown in FIG. It consists of a large-diameter support shaft 29 whose stepped surface abuts against the outer wall of the support portion 13.

Further, the hole portion at the outer end of the support shaft 29 is tapered,
The optical fiber 16 can be easily inserted. Also,
The inner diameter of the positioning fixture 17 is equal to the diameter of the optical fiber 16.
The diameter is slightly larger than 125 μm.

Further, the tip of the adjustment shaft 28 is cut into a bevel and has an inclined surface in order to increase the bonding area for fixing the optical fiber 16 to the adjustment shaft 28. Also,
As shown in FIG. 8, solder 30 to which no blank is attached is attached in advance to this cross-cut portion. The solder 30 is initially φ125μ
A dummy 31 that is slightly thicker than the optical fiber 16 of m, for example, a piano wire with a diameter of 150 μm, is inserted into the positioning fixture 17, and in this state, the adjustment shaft 2 of the positioning fixture 17 is inserted into the positioning fixture 17.
8, and then, as shown in FIG. 8, the piano wire serving as the dummy 31 is pulled out, and the attached flux and the like are removed by ultrasonic cleaning or the like. Note that this method of forming the solder 30 is based on the inner guide 26 of the fiber guide 4.
This is done in the same way when it is provided on the beveled part of the tip.

On the other hand, on the distal end of the positioning fixing body 17, that is, on the mounting portion 12 on the extension line of the distal end of the adjustment shaft 28, a submount 32 is soldered with fluxless low melting point solder, for example, Pb.
It is fixed with solder made of -3n-In. The submount 32 is made of insulating 5iC (α: 3.7×
It is composed of lO-bloC). Further, as shown in FIG. 9, a conductive metallized layer 33 is provided on the main surface of the submount 32. Then, on this metallized layer 33, an Au-5n eutectic layer 3 is provided.
A laser diode chip 15 and a pedestal 36 made of Au are fixed independently through 4.35. Therefore, the laser diode chip 15
The lower electrode is electrically connected to the pedestal 36 via the metallized layer 33. The laser diode chip 15 emits a laser beam 37, as shown in FIG.
A resonator 38 that emits light is fixed to the submount 32 in a so-called p-up state, which is far away from the submount 32. Further, the electrode on the upper surface of the laser diode chip 15 is electrically connected to the mounting portion 12 by two wires 20, and the pedestal 36 and the lead 6 are connected as shown in FIGS. 2 and 3. are electrically connected to each other by two wires 20. In this optoelectronic device, the connection of the upper electrode of the laser diode chip 15 to the mounting portion 12 and the connection of the pedestal 36 to the lead 6 by the wire 20 are connected to the side that drives the laser diode chip 15. This is to change the polarity so that it can be used as a negative because of the high speed transistor. Note that the laser diode chip 15 is fixed on the mounting portion 12 while being mounted on the submount 32.

Further, in the optoelectronic device of this embodiment, the laser diode chip 15 is offset from the center line of the heat sink 14 and biased to one side. This is to shorten the length of the wire 20 stretched between the pedestal 36 and the lead 6. By shortening the length of the wire 20, parasitic inductance is reduced, and the optoelectronic device can be used even in a high frequency range. This is for stable driving.

Furthermore, since the laser diode torch 15 is off the center line of the heat sink 14 and the positioning fixture 17 for guiding the optical fiber 16 is off the center line,
Fiber support 4 of package body subassembly parts
The positioning fixing body 17 is no longer located on the extension line.

As a result, if the optical fiber 16 extending from the fiber support 4 to the positioning fixture 17 is arranged so that no excessive force is applied, the optical fiber 16 will draw a curved line as shown in FIG. It will be extended. In this way, the fact that the optical fiber 16 extends in a curved line between the two fixed points means that even if the distance between the two fixed points changes due to temperature fluctuations, no unreasonable force is applied to the optical fiber 16. This eliminates the problem of communication. In other words, if the optical fiber 16 is stretched linearly between two fixed points, if the relative positional relationship between the two points of the optical fiber 16 changes due to thermal expansion or contraction, the light A force is applied to the fiber 16 or the optical fiber 16 is broken, but since the optical fiber 16 extends in a curved line as shown in FIG. The interval is from point A at room temperature to point B at high temperature.
When the optical fiber 16 is extended to a point or shrunk from the point A to the zero point in a low temperature state, the optical fiber 16 bends as shown by a dashed line or a dashed double dotted line to accommodate the change, so that no unreasonable stress is applied to the optical fiber 16. Therefore, damage to the optical fiber 16 can be prevented.

Further, a chip carrier 39 to which a light receiving element 18 is attached is fixed to the main surface of the heat sink 14 via an Au-3n eutectic layer. The chi-knob carrier 39 is made of a ceramic block, and is provided with an element fixing metallized layer 40 and a wire fixing metallized layer 41 over its lower side (principal surface) and upper surface, respectively. The light receiving element 18 is formed by the metallized layer 40 for fixing the element.
It is fixed on top with an Au-3i common layer interposed therebetween. Also,
The electrode on the upper surface of the light receiving element 18 and the wire fixing metallized layer 41 are electrically connected by a wire 42. Note that the chip carrier 39 is the chip carrier 3.
The light receiving element 18 is fixed to the heat sink 14 so that one side of the rectangle 9 coincides with one side of the heat sink 14.
The light-receiving surface is not perpendicular to the laser beam 37 but is oblique to the laser beam 37.

Therefore, since the light reflected from the light receiving surface of the light receiving element 18 does not return to the output surface of the laser diode chip 15, generation of noise due to the returned light can be prevented.

Further, on the upper surface of the support portion 13 of the heat sink 14,
A thermistor 19 that monitors the temperature of the heat sink 14
is fixed via a thermistor support chip 43.

The thermistor support chip 43 is made of a ceramic block and has metallized layers (not shown) on its front and back surfaces.

The thermistor 19 is fixed to the upper surface of the thermistor support chip 43 by the Au-3i common layer. As a result, the exposed metallized layer portion of the thermistor support chip 43 becomes electrically connected to the lower electrode of the thermistor 19. Therefore, in order to establish electrical conduction with the electrode holding portion 6 of the thermistor 19, as shown in FIGS.
0, and the predetermined glue portion 6 and the metallized layer of the thermistor support chip 43 are connected by two wires 20. Further, the heat sink 14 is provided with a recess 44 or a hole 45, as shown in FIG. As shown by the two-dot chain line in the figure, the tip of a position adjustment lever 46 or the like is inserted into these recesses 44 and holes 45, and a part of the peripheral wall of the recess 44 or hole 45 is inserted into the position adjustment lever. The adjustment shaft 28 of the positioning fixing body 17 is plastically deformed vertically and horizontally at the other end of the position adjustment lever 46 to align the optical axis with the optical fiber 16.

Subassembly of the subcarrier 11 having such a structure is performed in the following steps. First, the positioning fixing body 17 is inserted and fixed to the support portion 13 of the heat sink 14 by fluxless soldering. Next, the thermistor support/knob 43 on which the thermistor 19 is mounted is fixed onto the support portion 13 of the heat sink 14 by the Au-3n eutectic layer. Next, the chip carrier 3 on which the light receiving element 18 is mounted
9 is fixed to the heat sink 14 by an Au-3n eutectic layer. Finally, the submount 32 on which the laser diode chip 15 is mounted is fixed to the mounting portion 12 of the heat sink 14, and the subcarrier 11 as shown in FIG. 6 is manufactured.

Next, when assembling an optoelectronic device, first the subassembly parts and the Peltier element 10.
Fiber optic cable5. Individual parts such as package M8 are prepared. Thereafter, the Peltier element IO is fixed with fluxless solder 47 on the pedestal 9 fixed to the bottom of the package body 7 of the package body subassembly component. After that, the subcarrier 1 is placed on this Peltier element 10.
1 is fixed with fluxless solder. Next, the Peltier element lead 20 and the lead 6 are connected.

Next, the optical fiber cable 5 from which the jacket has been removed over a predetermined length from the tip is inserted into the fiber guide 4 and the positioning fixture 17, and the tip is inserted several tens of micrometers in front of the emission surface of the laser diode chip 15. be held still in position. In this state, the thin portion at the outer end of the fiber support 4 is caulked. As a result, the optical fiber cable 5 is temporarily fixed because the jacket portion is crushed by this caulking. Next, the optical fiber 16 portion at the inner end of the fiber support 4 is fixed by temporarily melting the ring-shaped fluxless solder 30.

Next, laser diode chip 15. Light receiving element 18.
The electrode of the thermistor 19 and the lead 6 are electrically connected using a wire 20. At this time, the wire 20 is connected by ultrasonic wire bonding, but when the wire 20 is connected to the upper end of the lead 6, since the lead 6 is reinforced with the reinforcing plate 22, the lead 6 is connected to the ultrasonic wire bonding. There is no vibration due to vibration during bonding, and reliable wire bonding can be performed.

Next, the laser diode chip 15 is driven to emit a laser beam 37, and this laser beam 37 is connected to the optical fiber 1.
The optical axis of the laser diode chip 15 and the optical fiber 16 is aligned after detecting the light intensity of the laser light 37 taken in from the tip of the laser diode chip 6 .

When aligning the optical axis, as shown in FIG.
This is done by plastically deforming the material two-dimensionally. Since the adjustment shaft 28 is plastically deformed, it does not return after the optical axis is aligned (and maintains the high optical coupling state at the time of setting for a long time).

Next, by attaching the package M8 to the opening of the package body 7 airtightly by soldering or the like, the fourth
An optoelectronic device as shown is assembled.

According to such an embodiment, the following effects can be obtained.

(1) According to the present invention, in the optoelectronic device, since the pedestal made of copper tungsten with good thermal conductivity is interposed between the Peltier element and the bottom of the package body, the Peltier element can be heated to high temperatures. Since heat dissipation on the side can be efficiently performed and the subcarriers on the Peltier element can be effectively cooled, the effect of stable operation of the optoelectronic device can be obtained.

(2) In the optoelectronic device of the present invention, the pedestal interposed between the Peltier element and the bottom of the package body has a coefficient of thermal expansion that approximates the coefficient of thermal expansion of the electrode plate of the Peltier element. Since it is made of copper tungsten, even when subjected to thermal cycles, no large thermal stress is applied between the electrode plate and the pedestal, and the solder connecting the pedestal and electrode plate will not suffer fatigue failure. The effect of stabilizing the reliability of the joint can be obtained.

(3) According to (2) above, in the optoelectronic device of the present invention, the solder that fixes the Peltier element to the pedestal does not deteriorate, so the thermal resistance of the solder is small and constant;
The effect is that cooling is stable and optical communication can be performed stably.

(4) According to the invention, a laser diode chip.

The light-receiving element, thermistor, and a positioning fixture that guides the optical fiber are integrated into the heat sink to form a subcarrier. In addition, the package body, flange,
The lead, pedestal, and fiber guide are integrated into a subassembly part of the package body. therefore,
When assembling optoelectronic devices, this subcarrier is
By fixing the laser diode chip on the Peltier element fixed to the seven-case main body subassembly, and by aligning the optical axis of the optical fiber and the laser diode chip fixed to the positioning fixing body of the subcarrier, important parts can be Since the assembly is completed, it is possible to assemble with high precision.

(5) According to the above (4), according to the present invention, since the assembly is performed using two sub-assembly parts and several individual parts, it is possible to obtain the effect of increasing productivity.

(6) During assembly of the optoelectronic device of the present invention, the optical axes of the laser diode chip and the optical fiber are aligned by oscillating position adjustment of the positioning fixing body of the subcarrier, resulting in highly accurate optical axis alignment. As a result, quality can be inherited.

(7) The optoelectronic device of the present invention changes the position of the positioning fixture when aligning the optical axes of the laser diode chip and the optical fiber, but this positional variation is performed by plastic deformation of the positioning fixture. After this, the optical coupling state does not return to its original state, so the optical coupling state at the time of setting can always be maintained, resulting in the effect of stable reliability.

(8) The optoelectronic device of the present invention has the following characteristics in the cage:
Since an optical fiber extends in a curved manner between two fixed points, even if there is a temperature change, the optical fiber will only change its curvature and extend, so there will be no damage to the optical fiber. This does not occur and the characteristics are stable.

(9) In the optoelectronic device of the present invention, since the laser diode chip is arranged biased to one side, the length of the wire stretched between the laser diode chip and the lead is shortened, and the high frequency It is also stable for use in the area.

(10) According to the above (1) to (9), according to the present invention,
A synergistic effect is obtained in that a highly accurate optoelectronic device that operates stably at a desired temperature can be provided at a low cost.

Although the invention made by the present inventor has been specifically explained above based on Examples, it goes without saying that the present invention is not limited to the above Examples and can be modified in various ways without departing from the gist thereof. For example, as shown in FIG.
If the structure is such that it is brought into close contact with the peripheral wall of the device, the heat dissipation effect will be further increased.

Further, as shown in FIG. 12, the optoelectronic device of the present invention may have a structure in which the flange 3 is provided on the bottom side of the package body 7 and the leads 6 protrude from both sides of the package body 7, similar to the above embodiment. Effects can be obtained.

In the above description, the invention made by the present inventor is mainly applied to the manufacturing technology of optoelectronic devices for optical communication, which is the background field of application, but the invention is not limited thereto.

The present invention can be applied to a technique of fixing a Peltier element to a pedestal using at least solder, and also has similar effects when fixed to an adhesive.

〔Effect of the invention〕

A brief explanation of the effects obtained by typical inventions disclosed in this application is as follows.

In the optoelectronic device for optical communication of the present invention, the pedestal interposed between the Peltier element and the bottom of the package has a coefficient of thermal expansion similar to that of the electrode plate made of alumina ceramic of the Peltier element, and has thermal conductivity. Since it is made of high-strength copper tungsten, the solder that connects the pedestal and the Peltier element is less likely to suffer fatigue damage, resulting in high reliability and good thermal conductivity, resulting in stable heat dissipation. , stable optical communication can be achieved.

[Brief explanation of drawings]

FIG. 1 is an enlarged cross-sectional view showing a state in which a Peltier element in an optoelectronic device according to an embodiment of the present invention is fixed to a stand via solder, FIG. 2 is a perspective view showing the main parts of the optoelectronic device, and FIG. 4 is a sectional view of the optoelectronic device, FIG. 5 is a perspective view of the package body, FIG. 6 is a perspective view of the subcarrier, and FIG. 8 is a sectional view showing the solder ring at the inner end of the positioning fixing body; FIG. FIG. 10 is a schematic diagram showing a fixed state of the optical fiber, FIG. 11 is a perspective view showing a photoelectronic device according to another embodiment of the present invention, and FIG. 12 is a schematic diagram showing a photoelectronic device according to another embodiment of the present invention. FIG. 101. Package, 2... Mounting hole to 3... Flange, 4... Fiber support, 5... Optical fiber cable, 6... Lead, 7... Package body, 8...
...Package lid, 9...Pedestal, 10...Peltier element, 11...Subcarrier, 12...Mounting section, 1
3... Support part, 14... Heat sink, 15...
Laser diode chip, 16... optical fiber, 17
... Positioning fixed body, 18... Light receiving element, 19...
- Thermistor, 20... Wire, 21... Insulating support, 22... Reinforcement plate, 23... Guide hole, 24...
... Support body, 24a... Support block, 25... Outer support body, 26... Inner support body, 27...
Electrode plate, 28...Adjustment shaft, 29...Support shaft, 30
...Solder, 31...Dummy, 32...Submount, 33...Metallization layer, 34.35...Au-
5n common product layer, 36... Pedestal, 37... Laser light, 38... Resonator, 39... Chip carrier, 4
0... Metalized layer for element fixing, 41... Metalized layer for wire fixing, 42... Wire, 43... Thermistor support chip, 44... Hole, 45... Hole, 4
6...Lever for position adjustment, 47...Solder, 48...
・Bending part.

Claims (1)

[Claims] 1. An electronic component comprising a package, a pedestal fixed to the bottom of the package, and a Peltier element mounted on the pedestal, the pedestal being a lower electrode plate of the Peltier element. An electronic component characterized by being made of a material with a coefficient of thermal expansion similar to that of the electronic component. 2. The electronic component according to claim 1, wherein the pedestal is made of copper tungsten. 3. The bottom of the package is provided with penetrating leads supported by Kovar glass, the pedestal is made of copper tungsten, and the Peltier element is fixed via solder. An electronic component according to claim 1. 4. The electronic component according to claim 1, wherein a subcarrier on which a laser diode chip is mounted is fixed on the Peltier element.