JP2006128736A - Package for housing optical semiconductor element - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a package for housing an optical semiconductor element, whose heat dissipation property is improved. <P>SOLUTION: The package includes a concave portion where a base 5 for placing an optical semiconductor element 6 and an optical fiber 8 thereon is provided; a substrate 1 for placing a drive circuit element 7 thereon, at the periphery of the concave portion; a thermally conductive member 10 provided to the portion 1b for placing the drive circuit element 7 of the substrate 1 thereon; and a frame body that is provided on the substrate 1 and has a through-hole through which the optical fiber is inserted, and to which a lid body is connected. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to an optical semiconductor element housing package for housing an optical semiconductor element.

  FIG. 5 shows a package for housing an optical semiconductor element (hereinafter referred to as an optical semiconductor package) for housing a semiconductor laser (LD), a photodiode (PD), etc. used in the conventional optical communication field. In the figure, the substrate 21 is a dielectric such as alumina (Al 2 O 3) ceramics, aluminum nitride (AlN) ceramics, glass ceramics, or a plate-like iron (Fe) − with a recess formed in the substantially central portion of the upper surface thereof. It consists of metal materials, such as a nickel (Ni) -cobalt (Co) alloy and a copper (Cu) -tungsten (W) alloy. In addition, the optical semiconductor element 26 and the end of the optical fiber 28 are attached to the bottom surface of the recess through the mounting base 25 by a low melting point brazing material such as gold (Au) -germanium (Ge) solder. And a placement portion 21b for placing a drive circuit element 27 for inputting / outputting a drive signal to / from the optical semiconductor element 26 at the periphery of the recess.

  The mounting base 25 is made of a silicon substrate or the like having excellent heat dissipation and workability. The optical semiconductor element 26 is mounted on the upper surface of the mounting base 25 and the end of the optical fiber 28 is positioned by passive alignment. It has the mounting part 25a in which a groove | channel with a substantially V-shaped cross section is formed.

  The optical semiconductor element 26 and the drive circuit element 27 are attached to the mounting portions 25a and 21b by low melting point solder such as gold-tin (Sn) solder and tin-lead (Pb) solder, respectively. Further, the heat generated when the optical semiconductor element 26 and the drive circuit element 27 are operated is absorbed by the base 21 and the mounting base 25 through these low melting point solders and radiated to the atmosphere.

  Further, through holes 22a are formed in the side portions made of a metal material such as an Fe-Ni-Co alloy or a Cu-W alloy so as to surround the mounting base 25 and the drive circuit element 27 on the outer peripheral portion of the upper surface of the base 21. The frame body 22 having the above is attached.

  Further, a cylindrical fixing member 24 for inserting and fixing the optical fiber 28 is attached to the periphery of the through hole 22a on the outer surface of the frame body 22 or the inner peripheral surface of the through hole 22a with a brazing material such as silver brazing.

  In addition, electrode pads 29 for electrically connecting the optical semiconductor package and the external electric circuit board are provided along two opposite sides of the lower surface of the base 21. As a result, it is possible to reduce reflection loss that occurs when a high-frequency signal is transmitted between the optical semiconductor package and the external electric circuit board, and to reduce a mounting deviation when the optical semiconductor package is mounted on the external electric circuit board. As a result, input / output of high-frequency signals into the optical semiconductor package is performed efficiently and smoothly. Then, the optical semiconductor package is attached to the external electric circuit board via the electrode pads 29 and the conductor bumps such as the solder paste made of tin-lead solder, tin-silver (Ag) solder or the like formed on the external electric circuit board. Be joined.

  Further, in order to seal the optical semiconductor element 26 and the drive circuit element 27 on the upper surface of the frame 22, a metal material such as Fe—Ni—Co alloy or Fe—Ni alloy, alumina ceramics, aluminum nitride ceramics, glass A lid 23 made of a dielectric material such as ceramic or a resin such as epoxy resin is joined by seam welding, brazing, resin adhesive, or the like.

  Then, the optical semiconductor element 26 and the drive circuit element 27 are hermetically accommodated in the optical semiconductor package to improve the operability.

  In this way, the optical semiconductor element 26 and the drive circuit element 27 are accommodated in the optical semiconductor package by the base body 21, the frame body 22, and the lid body 23, and the optical semiconductor element attached to the mounting portions 25a and 21b. 26, the drive circuit element 27, and the external electric circuit board are electrically connected to form an optical semiconductor package that inputs and outputs high-frequency signals to and from the optical semiconductor element 26.

  However, since the drive circuit element 27 accommodated in the conventional optical semiconductor package has been rapidly increased in density and integration in recent years, it is generated from the drive circuit element 27 when the optical semiconductor package is operated. The amount of heat to be generated is extremely large as compared with the prior art. Further, in accordance with the market demand for miniaturization and weight reduction of the optical semiconductor package, the drive circuit element 27 such as LSI or IC is placed in the vicinity of the optical semiconductor element 26 and operated. As a result, heat generated from the drive circuit element 27 is transmitted to the optical semiconductor element 26 through the base 21, the mounting base 25, and the atmosphere in the optical semiconductor package, and the optical semiconductor element 26 is heated. The optical semiconductor element 26 has a problem that the temperature is higher than a temperature at which the optical semiconductor element 26 can operate normally and stably over a long period of time.

  For example, when the optical semiconductor element 26 is heated to 70 ° C. or higher including its own heat generation, the function of photoexcitation decreases. When the output of the drive circuit element 27 placed in the vicinity of the optical semiconductor element 26 is 2 W, the temperature rises to about 200 ° C. in the vicinity of the output, so that the optical semiconductor element 26 is heated by the heat of the drive circuit element 27. It had the problem of being heated to 70 ° C or higher.

  As a means for solving such a problem, a configuration in which a thermoelectric cooling element such as a Peltier element is installed in the lower portion of the mounting base 25 to cool the optical semiconductor element 26 can be adopted. It is disadvantageous in terms of thinning, and has a problem that it is inferior in practicality.

  In addition, the base 21 of the mounting portion 21a can be thinned to improve the thermal conductivity of the base 21. However, when the base 21 is thinned, the base 21 and the frame 22 are made of a brazing material such as silver solder. And the distortion of the base body 21 that occurs when attaching is increased. As a result, the mounting deviation when mounting the optical semiconductor package on the external electric circuit board also increases. Therefore, transmission loss and reflection loss generated when inputting / outputting a high-frequency signal to / from the optical semiconductor package are large, and there is a problem that high-frequency signal input / output in the GHz band is not smoothly performed.

  Further, if the thickness of the base 21 of the mounting portion 21a is reduced, the heat diffusibility of the base 21 is deteriorated, so that the heat generated from the optical semiconductor element 26 and the drive circuit element 27 is stored in the base 21 and efficiently. There was a problem that heat was not released into the atmosphere.

  Further, by widening the distance between the optical semiconductor element 26 and the drive circuit element 27, the amount of heat generated from the drive circuit element 27 and transmitted to the optical semiconductor element 26 via the base 21 and the mounting base 25 is reduced. However, this configuration does not sufficiently satisfy the demand for higher density, higher integration, and smaller size in the optical semiconductor package, and the transmission line for high-frequency signals becomes longer, resulting in increased transmission loss. Had problems.

  In addition, although a structure in which the heat dissipation of the optical semiconductor package is improved by using a dielectric having high thermal conductivity as the base 21 can be adopted, the heat generated from the drive circuit element 27 and the optical semiconductor element 26 is generated by the base 21 and the frame. 22 is transmitted to the entire optical semiconductor package via the lid 23. As a result, the optical semiconductor package itself becomes a high-temperature heat source, and there is a problem that the optical semiconductor element 26 and the drive circuit element 27 are heated.

  Further, as another conventional example, in order to reduce the thermal conductivity between the optical semiconductor element and the drive circuit element, a unidirectional heat conductive member is embedded in the base of the optical semiconductor package, and the optical semiconductor element and the drive circuit element are There has been proposed a configuration in which a region to be placed is divided (see Japanese Patent Application Laid-Open No. 2000-164742). However, since it is necessary to form the wiring pattern in the optical semiconductor package while avoiding the unidirectional heat conducting member, the degree of freedom of the wiring pattern is lowered and the transmission line is lengthened. As a result, transmission loss generated when transmitting a high-frequency signal in the GHz band is increased, and high-frequency signal input / output between the optical semiconductor element and the drive circuit element cannot be performed efficiently and smoothly.

  Accordingly, the present invention has been completed in view of the above problems, and an object of the present invention is to provide an optical semiconductor package that inputs and outputs a high-frequency signal in the GHz band without reducing the transmission characteristics of the high-frequency signal. It is intended to make the optical semiconductor package smaller, thinner, and lighter by improving the heat dissipation of the inside and omitting thermoelectric cooling elements such as Peltier elements. Another object is to effectively prevent the temperature increase of the optical semiconductor element by suppressing the amount of heat transferred from the drive circuit element to the optical semiconductor element. Furthermore, the heat generated from the optical semiconductor element and the drive circuit element is diffused throughout the optical semiconductor package, thereby effectively preventing the optical semiconductor package itself from becoming a high-temperature heat source.

  The present invention has a recess in which an optical semiconductor element and an optical fiber mounting base are provided, a base on which a drive circuit element is mounted around the recess, and mounting of the drive circuit element on the base A heat conducting member provided on the portion; and a frame provided on the base body, having a through-hole into which the optical fiber is inserted, and having a lid joined thereto. To do.

  The present invention has a recess in which an optical semiconductor element and an optical fiber mounting base are provided, a base on which a drive circuit element is mounted around the recess, and mounting of the drive circuit element on the base And a heat conducting member provided on the base, and a frame provided on the base, having a through-hole into which the optical fiber is inserted, and having a lid joined thereto. Characteristics can be improved.

  The optical semiconductor package of the present invention will be described in detail below. FIG. 1 is a cross-sectional view of an optical semiconductor package of the present invention, and FIG. 2 is a top view thereof. In these drawings, 1 is a base, 2 is a frame, and 3 is a lid. The base body 1, the frame body 2, and the lid body 3 basically constitute a container in which an optical semiconductor element 6 and a drive circuit element 7 made of LSI, IC, etc. for driving the optical semiconductor element 6 are housed.

  The substrate 1 is made of a dielectric such as alumina (Al 2 O 3) ceramics and functions as a support member that supports the optical semiconductor element 6 and the drive circuit element 7. Further, on the bottom surface of the recess formed in the substantially central portion of the upper surface, a mounting base 5 having a mounting portion 5a on which the end portions of the optical semiconductor element 6 and the optical fiber 8 are mounted is Au- It has the mounting part 1a attached by solder materials, such as Ge solder. In addition, the outer peripheral portion of the upper surface of the concave portion has a placement portion 1 b that is disposed in the vicinity of the optical semiconductor element 6 and on which a drive circuit element 7 that drives the optical semiconductor element 6 is placed. The substrate 1 may be made of multilayer ceramics.

  A frame body 2 is attached to the outer peripheral portion of the upper surface of the base 1 so as to surround the mounting section 1a and the mounting section 1b, and an optical semiconductor element 6 and a drive circuit element are disposed inside the frame body 2. 7 and a space for accommodating the mounting base 5 are formed. The frame body 2 is formed into a predetermined shape by multilayering ceramics, and a through hole 2a is formed in a side portion thereof, and silver brazing or the like is interposed through a metallized layer attached to the lower surface of the frame body 2. The brazing material is attached to the upper surface of the substrate 1. In addition, the frame 2 may be comprised from metal materials, such as a Fe-Ni-Co alloy and Cu-W alloy, and by making ingots (lumps), such as a Fe-Ni-Co alloy, into a frame shape by press work It is formed. Furthermore, a cylindrical fixing member 3 for fixing the optical fiber 8 to the periphery of the opening on the outer surface side of the frame body 2 or the inner peripheral surface of the through hole 2a is attached to the through hole 2a.

  The substrate 1 is made into a paste by adding and mixing an appropriate organic binder or solvent to the raw material powder, and this paste is formed into a ceramic green sheet by a doctor blade method or a calender roll method, and then a ceramic green sheet. A suitable punching process is applied to the substrate, and a plurality of these are laminated and fired at a high temperature of about 1600 ° C.

  Further, the metallized layer made of tungsten (W), molybdenum (Mo), manganese (Mn), etc. formed as a wiring pattern on the surface of the substrate 1 and the frame 2 or inside the optical semiconductor package is provided on the outer surface thereof. A metal layer having excellent corrosion resistance and good wettability to the brazing material, for example, a Ni plating layer having a thickness of 1.5 to 6 μm and an Au plating layer having a thickness of 0.2 to 5 μm are sequentially deposited. It is good. In this case, it is possible to effectively prevent the base body 1 from being oxidatively corroded, and the mounting base 5, the frame body 2, the drive circuit element 7 and the bonding wire can be firmly attached to the base body 1.

  In addition, electrode pads 9 are provided on the lower surface of the substrate 1 for electrically connecting the optical semiconductor package and the external electric circuit board along two opposite sides. Compared with the lead terminal, the electrode pad 9 can reduce reflection loss caused when a high-frequency signal is transmitted between the optical semiconductor package and the external electric circuit board, and mount the optical semiconductor package on the external electric circuit board. In this case, it is possible to suppress the deviation of the mounting that occurs. The optical semiconductor package is attached to the external electric circuit board via a solder paste made of Sn-Pb solder, Sn-Ag solder or the like formed on the external electric circuit board, a conductor bump such as a solder ball, and the electrode pad 9. Worn.

  The electrode pad 9 is formed of a metallized layer such as W, Mo, or Mn. For example, a metal paste obtained by adding and mixing an organic solvent, a solvent, or the like to a powder such as W is used as a ceramic before firing the substrate 1. It is formed by printing and applying a predetermined pattern on a green sheet in advance by a well-known screen printing method and baking.

  Furthermore, on the surface of the electrode pad 9, a metal excellent in heat resistance and wettability with the brazing material, specifically, a Ni layer having a thickness of 0.5 to 9 μm and an Au having a thickness of 0.5 to 5 μm The layers are preferably deposited sequentially, and the electrode pad 9 can be effectively prevented from oxidative corrosion. Further, since the optical semiconductor package can be firmly bonded to the external electric circuit board via the conductor bumps, the distortion of the base 1 and the mounting base 5 caused by the environmental test such as the temperature cycle test and the thermal shock test can be reduced. As a result, the optical axis misalignment between the optical semiconductor element 6 and the optical fiber 8 placed on the top surface of the placement substrate 5 is reduced, and fluctuations in optical coupling efficiency can be suppressed. The planar shape of the electrode pad 9 is not limited to a circular shape, and may be an elliptical shape or a polygonal shape.

  In the present invention, the substrate 1 uses a dielectric having a thermal conductivity of 10 to 25 W / m · K. For example, when glass ceramics having a thermal conductivity of less than 10 W / m · K is used as the base 1, heat generated from the optical semiconductor element 6 and the drive circuit element 7 can be efficiently transmitted to the lower surface of the base 1. Therefore, the heat dissipation of the optical semiconductor package is reduced.

  For example, when an aluminum nitride ceramic having a thermal conductivity of more than 25 W / m · K is used as the base 1, the heat generated from the optical semiconductor element 6 and the drive circuit element 7 is generated by the base 1, the frame 2, and the lid 3. The optical semiconductor package itself becomes a high-temperature heat source. As a result, the optical semiconductor element 6 and the drive circuit element 7 are heated to a temperature at which the optical semiconductor element 6 and the drive circuit element 7 are at a temperature at which they do not function normally and stably over a long period of time.

  Moreover, in this invention, the thickness of the base | substrate 1 of the site | part corresponded to the mounting part 1a shall be 0.6-20 mm. When the thickness is less than 0.6 mm, the base 1 has a low heat diffusivity, and therefore efficiently absorbs heat generated from the optical semiconductor element 6 and the drive circuit element 7 and cannot radiate it into the atmosphere. In addition, the distortion of the substrate 1 generated when an optical semiconductor package is assembled using silver solder having a melting point of about 780 ° C. is increased. As a result, the optical semiconductor element 6 and the drive circuit element 7 are at or above the temperature at which they can operate normally and stably over a long period of time. In addition, the mounting displacement that occurs when the optical semiconductor package is mounted on the external electric circuit board increases, and transmission loss and reflection loss when inputting and outputting a high-frequency signal increase.

  Here, when the optical semiconductor element 6 and the drive circuit element 7 are driven, the temperature of the junction between the optical semiconductor element 6 and the drive circuit element 7 and the mounting portions 5a and 1b (hereinafter referred to as the chip junction temperature). An example of the measurement result will be described. The measurement conditions are as follows: alumina ceramic having a thermal conductivity of 15 W / m · K is used as the substrate 1, GaAs semiconductor elements are driven as the optical semiconductor element 6 and the drive circuit element 7, and the optical semiconductor package is cooled by the surroundings. Natural cooling was performed at a temperature of 25 ° C.

  First, when the optical semiconductor element 6 and the drive circuit element 7 are operated by setting the thickness of the mounting portion 1a of the base body 1 to 1 mm and the distance between the optical semiconductor element 6 and the drive circuit element 7 to about 7 mm, The chip junction temperature was 69.1 ° C., and the chip junction temperature of the drive circuit element was 106.4 ° C. This satisfies a chip junction temperature of 75 ° C. or lower, which is generally required for the optical semiconductor element 6 to operate normally and stably over a long period of time. Further, it satisfies a chip junction temperature of 110 ° C. or lower, which is generally required for the drive circuit element 7 to operate normally and stably over a long period of time. That is, the base 1 efficiently dissipates heat generated from the optical semiconductor element 6 and the drive circuit element 7 into the atmosphere via the base, and the base 1, the mounting base 5, and the optical semiconductor from the drive circuit element 7. It has been found that heat transferred to the optical semiconductor element 6 through the atmosphere in the package can be effectively suppressed.

  Furthermore, when the optical semiconductor element 6 and the drive circuit element 7 are operated with the thickness of the mounting portion 1b of the base body 1 being 0.5 mm and the distance between the optical semiconductor element 6 and the drive circuit element 7 being approximately 7 mm, the optical semiconductor element 6 has a chip junction temperature of 69.7 ° C. and the drive circuit element 7 has a chip junction temperature of 114.2 ° C., which is generally necessary for the drive circuit element 7 to operate normally and stably over a long period of time. The chip junction temperature condition to be satisfied could not be satisfied. That is, it has been found that the heat generated from the optical semiconductor element 6 and the drive circuit element 7 is not efficiently dissipated into the atmosphere through the substrate 1 in the above configuration.

  Further, when the thickness of the substrate 1 corresponding to the mounting portion 1a is thicker than 2 mm, the distortion of the substrate 1 generated when the optical semiconductor package is assembled is reduced and the heat diffusibility of the substrate 1 is improved. The market requirements for miniaturization, height reduction, and weight reduction of optical semiconductor packages cannot be fully satisfied. Moreover, the transmission line of the high frequency signal between the wiring pattern formed on the upper surface of the substrate 1 and the electrode pad 9 installed on the lower surface of the substrate 1 becomes longer, and the transmission loss increases.

  Moreover, the optical semiconductor element 6 and the drive circuit element 7 are placed so that the interval is 6 to 20 mm. When the interval is smaller than 6 mm, the amount of heat transferred from the drive circuit element 7 to the optical semiconductor element 6 through the atmosphere in the base 1, the mounting base 5, and the optical semiconductor package increases. The temperature rises.

  When the distance between the optical semiconductor element 6 and the drive circuit element 7 is wider than 20 mm, the drive circuit element 7 transmits the optical semiconductor element 6 to the optical semiconductor element 6 through the base 1, the mounting base 5, and the atmosphere in the optical semiconductor package. Although the amount of heat that is generated is suppressed, the transmission loss of the high-frequency signal between the optical semiconductor element 6 and the drive circuit element 7 becomes longer, so the transmission loss increases. Further, the demand for miniaturization and high integration of the optical semiconductor package cannot be sufficiently satisfied.

  In the optical semiconductor package of the present invention, a through hole 1c that penetrates the upper and lower surfaces of the substrate 1 is formed in a portion corresponding to the mounting portion 1b of the drive circuit element 7, and the thermal conductivity is 130 W / in the through hole 1c. It is preferable to insert and join a heat conductive member 10 of m · K or more. As a result, heat generated when the drive circuit element 7 operates is efficiently transferred to the lower surface of the optical semiconductor package via the heat conducting member 10 and radiated to the atmosphere. Therefore, the drive circuit element 7 is always at an appropriate temperature, and heat transmitted to the optical semiconductor element 6 via the base 1 and the mounting base 5 can be effectively suppressed.

  In addition, the heat conductive member 10 consists of metal materials, such as a copper (Cu) -tungsten alloy and Cu-Mo alloy, for example. In addition, a unidirectional composite material in which carbon fibers arranged in one direction are bonded with carbon may be used.

  According to the present invention, the heat generated from the optical semiconductor element 6 and the drive circuit element 7 can be efficiently radiated from the base 1 to the atmosphere without deteriorating the transmission characteristics of the high frequency signal. In addition, since a dielectric having a moderately low thermal conductivity is used as the substrate 1, heat generated from the optical semiconductor element 6 and the drive circuit element 7 diffuses throughout the optical semiconductor package, and the optical semiconductor package itself is a high-temperature heat source. Can be prevented. Further, since the amount of heat transferred from the drive circuit element 7 to the optical semiconductor element 6 through the base 1, the mounting base 5, and the atmosphere in the optical semiconductor package can be suppressed, the temperature rise of the optical semiconductor element 6 can be suppressed. Can do. As a result, the optical semiconductor element 6 and the drive circuit element 7 can be operated normally and stably over a long period of time, and the optical semiconductor package can be reduced in size and thickness by omitting thermoelectric cooling elements such as Peltier elements. , Enabling weight reduction.

  3 and 4 show another example of the embodiment of the optical semiconductor package of the present invention. These drawings are configurations for reducing the influence of radiant heat (radiant heat) emitted from the drive circuit element 7, which is one of the factors that raise the temperature of the optical semiconductor element 6. FIG. As shown in FIG. 3, by making the upper surface of the heat conducting member 10 where the drive circuit element 7 is placed lower than the upper surface of the substrate 1, the radiant heat propagating from the drive circuit element 7 to the optical semiconductor element 6 is effectively utilized. Can be reduced. The height of the heat conduction member 10 at the portion where the drive circuit element 7 is placed is the length of the bonding wire for electrically joining the electrode on the upper surface of the drive circuit element 7 and the wiring pattern on the upper surface of the substrate 1. In order to shorten the length and reduce the transmission loss of the high-frequency signal, when the drive circuit element 7 is placed on the upper surface of the heat conducting member 10, the upper surface of the drive circuit element 7 and the upper surface of the substrate 1 are flush with each other. It is preferable to form.

  In addition, as shown in FIG. 4, by providing the standing wall portion 1 d between the optical semiconductor element 6 and the drive circuit element 7, it is possible to effectively reduce the radiant heat propagating from the drive circuit element 7 to the optical semiconductor element 6. it can. In addition, it is preferable that the height of the standing wall portion 1d is not less than the height of the drive circuit element 7 and the length thereof is not less than the length of the drive circuit element 7. With these configurations, when the optical semiconductor package operates, radiant heat propagating from the drive circuit element 7 to the semiconductor element can be effectively reduced, and heating of the optical semiconductor element 6 can be effectively suppressed.

  Further, the fixing member 4 has a function of fixing the optical fiber 8 to the frame body 2, and is formed on a metallized layer that is attached around the outer opening of the through hole 2 a of the frame body 2 or on the inner peripheral surface of the through hole 2 a. It is joined via a brazing material such as silver brazing. The fixing member 4 is made of a metal material such as an Fe-Ni-Co alloy or a Cu-W alloy. For example, the fixing member 4 is formed by forming an ingot such as an Fe-Ni-Co alloy into a cylindrical shape by pressing. The An optical fiber 8 is inserted into the fixing member 4 and is fixed by an adhesive 11 such as resin or solder, and airtightness inside the optical semiconductor package is maintained. When a solder material is used as an adhesive, a metallized layer is previously deposited on the outer peripheral surface of the joint portion of the optical fiber 8 by a conventionally known metallization method.

  Note that a lid 3 made of a metal material such as an Fe—Ni—Co alloy or Fe—Ni alloy is attached to the upper surface of the frame 2, and the attachment is performed by, for example, welding by a seam weld method or the like. Or by soldering with a low melting point brazing material such as Au—Sn alloy solder. As a result, the optical semiconductor element 6 and the drive circuit element 7 are hermetically sealed inside the container including the base body 1, the frame body 2, and the lid body 3.

  Thus, in the optical semiconductor package of the present invention, the optical semiconductor element 6 and the drive circuit element 7 are attached to the placement portion 5a and the placement portion 1b via a solder material such as Au-Sn solder, Sn-Pb solder, It is electrically connected to a wiring pattern formed inside the optical semiconductor package by a bonding wire. After that, the lid 3 is attached to the upper surface of the frame 2 via a low melting point brazing material such as Au—Sn alloy solder, and the container comprising the base body 1, the frame 2, the fixing member 4, and the lid 3. By accommodating the optical semiconductor element 6 and the driving circuit element 7 in the optical semiconductor device as a product.

  It should be noted that the present invention is not limited to the above-described embodiment, and various modifications can be made without departing from the scope of the present invention.

  For example, by providing the electrode pad 9 on the lower surface of the heat conducting member 10 fitted into the through hole 1c, the heat generated from the drive circuit element 7 is transmitted to the external electric circuit board through the heat conducting member 10 and the electrode pad 9. Thus, heat can be radiated more efficiently. Further, without using the fixing member 4 for fixing the optical fiber 8, a substantially U-shaped or substantially inverted U-shaped cutout is provided on the side surface of the frame body 2, the optical fiber 8 is fitted, and solder material or resin is provided. You may fix with adhesives, such as.

  In an optical semiconductor package having a driving frequency band of 1 GHz or more, the present invention has a driving frequency band of a driving circuit element of 1 GHz or more, and the substrate is made of a dielectric having a thermal conductivity of 10 to 25 W / m · K. The thickness of the portion corresponding to the mounting portion is 0.6 to 2 mm, and the distance between the optical semiconductor element and the drive circuit element is 6 to 20 mm. Since the heat dissipation of the package can be improved and a thermoelectric cooling element such as a Peltier element can be omitted, the optical semiconductor package can be reduced in size, thickness, and weight. Further, the amount of heat transferred from the drive circuit element to the optical semiconductor element can be suppressed, and the optical semiconductor package itself can be effectively prevented from becoming a high-temperature heat source.

  Further, according to the present invention, preferably, a heat conductive member having a thermal conductivity of 130 W / m · K or more is fitted and joined into a through-hole penetrating the upper and lower surfaces of the base, which is formed in a portion where the drive circuit element is placed. Thus, heat generated from the drive circuit element can be efficiently transferred to the lower surface of the optical semiconductor package via the heat conducting member and radiated to the atmosphere. Therefore, the drive circuit element is always at an appropriate temperature, and heat transferred from the drive circuit element to the optical semiconductor element can be effectively prevented.

It is sectional drawing which shows an example of embodiment about the optical semiconductor package of this invention. It is a top view of the optical semiconductor package of FIG. It is sectional drawing which shows the other example of embodiment about the optical semiconductor package of FIG. It is sectional drawing which shows the other example of embodiment about the optical semiconductor package of FIG. It is sectional drawing of the example of the conventional optical semiconductor package.

Explanation of symbols

1: Substrate 1a, 1b: Placement part 1c: Through hole 2: Frame body 3: Cover body 5: Mounting base 6: Optical semiconductor element 7: Drive circuit element 8: Optical fiber 10: Thermal conduction member

Claims (2)

A substrate having a recess in which an optical semiconductor element and an optical fiber mounting base are provided, and a base on which a drive circuit element is mounted around the recess;
A heat conducting member provided on a mounting portion of the drive circuit element of the base;
A package for housing an optical semiconductor element, comprising: a frame provided on the substrate, having a through hole into which the optical fiber is inserted, and having a lid joined thereto. 2. The optical semiconductor element housing package according to claim 1, wherein the base is made of ceramics.

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