JP4779919B2 - Photoelectric conversion device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an optoelectric converter capable of restraining its deformation due to temperature change. <P>SOLUTION: The optoelectric converter 1B comprises: a light-emitting element 4A for converting an electric signal to a light signal; an IC circuit 50A for transmitting the electric signal to the light-emitting element 4A; a mount substrate 3 where the light-emitting element 4A is packaged; an electric connector 6 attached to or detached from an external connector 7; and a waveguide 9 optically coupled to the light-emitting element 4A. In the optoelectric converter 1B, the electric connector 6 is provided on one surface 3a where the light-emitting element 4A and the IC circuit 50A of the mount substrate 3 are packaged. An interposer substrate 8 for changing an electrode pattern is provided between the mount substrate 3 and the electric connector 6. The interposer substrate 8 is formed by the same silicon resin as that of the mount substrate 3. <P>COPYRIGHT: (C)2008,JPO&amp;INPIT

Description

  The present invention relates to a photoelectric conversion apparatus including an optical element.

  Conventionally, as a photoelectric conversion device, for example, as described in FIG. 9 of Patent Document 1, a light emitting element that emits light by converting an electric signal into an optical signal, and an electric signal for transmitting the light signal to the light emitting element An IC circuit is formed, the substrate mounted on one surface from the side opposite to the light emitting element emits light, and disposed so as to extend from the light emitting element in a direction perpendicular to one surface of the substrate, so that the light emitting element emits light. One having a waveguide for transmitting light is known. In place of the light emitting element, a light receiving element that converts a received optical signal into an electric signal may be used.

Moreover, in the photoelectric conversion apparatus described in FIG. 9 of Patent Document 1, a female electrical connector provided on the wiring board and a detachable male electrical connector are provided on the other surface of the substrate. By connecting these electrical connectors, the substrate and the wiring substrate are electrically connected.
JP 2001-42170 A

  However, in the configuration as described above, since the waveguide is disposed so as to extend from the light emitting element in a direction orthogonal to the one surface of the substrate, the height of the entire apparatus becomes considerably high.

  Here, as described in FIG. 3 of Patent Document 1, an electrical connector may be provided on the end face of the substrate so that the light emitting element emits light in a direction parallel to the wiring substrate. However, the height of the device is at least as large as the size of the light emitting element and the size of the control IC element, so that the height of the device cannot be suppressed so much.

  Therefore, the applicant of the present application mounts the optical element on one side of the mount substrate from the light emitting side or the light receiving side so that the apparatus can be reduced in height, and the optical element is mounted on the mount substrate. An IC circuit for the element is provided and an electrical connector that can be attached to and detached from the external connector is provided on one surface of the mount substrate or the other surface on the opposite side, and a waveguide that is optically coupled to the optical element is provided on one surface of the mount substrate or A photoelectric conversion device provided on the mount substrate along the other surface has been proposed.

  With this photoelectric conversion device, the overall height of the device in the thickness direction of the mount substrate can be suppressed, and the device can be reduced in height.

  In such a photoelectric conversion device, an interposer substrate (intermediate substrate) is disposed between the mount substrate and the electrical connector, and the electrode pattern is converted by the interposer substrate to electrically connect the mount substrate and the electrical connector. In this case, since the number of components increases, the device is likely to be deformed due to a temperature change. Therefore, it is desirable to suppress the deformation of the device.

  In view of such a demand, an object of the present invention is to provide a photoelectric conversion device capable of suppressing deformation of the device due to temperature change.

  The invention of claim 1 is an optical element that converts an electrical signal into an optical signal or an optical signal into an electrical signal, and an IC circuit that transmits an electrical signal to or receives an electrical signal from the optical element, A mounting board on which the optical element is mounted; an electrical connector that can be attached to and detached from an external connector; and a waveguide that is optically coupled to the optical element, wherein the electrical connector includes the optical element on the mounting board and the optical board. The photoelectric conversion device is provided on one surface on which the IC circuit is mounted or the other surface on the opposite side, and the waveguide is provided on the mount substrate along one surface or the other surface of the mount substrate. An intermediate substrate for changing an electrode pattern is provided between the mount substrate and the electrical connector, and the intermediate substrate is formed of a material having a linear expansion coefficient substantially equal to that of the mount substrate. It is characterized in that there.

  According to a second aspect of the present invention, in the photoelectric conversion apparatus according to the first aspect, the intermediate substrate is provided in surface contact with one surface of the mount substrate, and the intermediate substrate is disposed on a surface facing the mount substrate. Is provided with a recess capable of accommodating the optical element and the IC circuit on the mount substrate, and in the periphery of the recess of the intermediate substrate, the mount substrate is electrically contacted with the mount substrate. A through-wiring connected to is provided.

  According to a third aspect of the present invention, in the photoelectric conversion apparatus according to the first or second aspect, the mount substrate is made of silicon, and the intermediate substrate is selected from the group consisting of silicon, glass, and ceramics. It is characterized by being formed of a material.

  According to the first aspect of the present invention, since the linear expansion coefficient of the intermediate substrate is substantially equal to the linear expansion coefficient of the mount substrate, even if the number of constituent members of the device is increased by providing the intermediate substrate, the device accompanying the temperature change The deformation is not likely to occur. Thereby, even when an intermediate substrate is provided, deformation of the apparatus can be suppressed.

  According to the second aspect of the present invention, the concave portion that accommodates the optical element and the IC circuit is provided in the intermediate substrate, and the intermediate substrate is directly electrically connected to the mount substrate by the through wiring arranged around the concave portion. Since solder balls that serve to electrically connect the substrates are not required, the number of members and the height of the apparatus can be reduced. In this case, the bonding reliability of both substrates can be improved by directly connecting the mount substrate and the intermediate substrate without using solder balls or the like.

  Further, since the optical element and the IC circuit are accommodated in the recess, the optical element and the IC circuit can be sealed between the mount substrate and the intermediate substrate and protected from moisture, dust, and the like.

  According to the invention of claim 3, when the intermediate substrate is formed of silicon, the linear expansion coefficient of the intermediate substrate can be made equal to the linear expansion coefficient of the mount substrate, so that the deformation of the apparatus can be more reliably suppressed. it can. In addition, a wiring pattern corresponding to the electrode of the electrical connector can be easily formed on the surface of the intermediate substrate facing the electrical connector. Further, the concave portion can be formed at low cost and with high accuracy using a technique such as anisotropic etching. In addition, since the mount substrate and the intermediate substrate can be manufactured consistently at the wafer level by the silicon process in the manufacturing process of the device, the manufacturing cost can be kept low.

  In addition, when the intermediate substrate is formed of glass, heat dissipation against heat generated in the optical element and the IC circuit can be improved.

  In addition, when the intermediate substrate is formed of ceramics, high frequency characteristics can be improved.

  Hereinafter, the best mode for carrying out the present invention will be described in detail with reference to the drawings.

  First, with reference to FIGS. 1 to 7, the photoelectric conversion apparatus 1A previously proposed by the applicant will be described as a reference example. This photoelectric conversion device 1A includes a light emitting side photoelectric conversion unit (also referred to as an E / O module) 1A1 that is mounted on one wiring board 2 by fitting electrical connectors 6 and 7, and another wiring board 2. Similarly, a light-receiving side photoelectric conversion part (also referred to as an O / E module) 1A2 that is mounted by fitting the electrical connectors 6 and 7 and an external waveguide 9 that optically connects these conversion parts 1A1 and 1A2. I have.

  In the present specification, the vertical direction in FIG. 1 is referred to as the vertical direction, the direction orthogonal to the paper surface in FIG. 1 is referred to as the horizontal direction, and the right side in FIG. The left side of FIG. 1 is referred to as the front side and the right side is referred to as the rear side with respect to the light-receiving side photoelectric conversion unit 1A2.

  The light emission side photoelectric conversion unit 1A1 includes a mount substrate 3 having a rectangular shape extending in the front-rear direction in plan view. As shown in FIG. 2, a light emitting element 4A that converts an electric signal into an optical signal to emit light and an IC for transmitting the electric signal to the light emitting element 4A are provided on one surface 3a that is the lower surface of the mount substrate 3. An IC substrate 5A on which a circuit 50A is formed is mounted, and a header type electrical connector (hereinafter simply referred to as “header”) 6 is provided so as to cover these 4A and 5A from below. In addition, on one surface 3a of the mount substrate 3, a driving power supply line and a signal line for the light emitting element 4A are formed by a wiring pattern 36 (see FIG. 4). Further, the mount substrate 3 is provided with a mirror portion 33 that converts an optical path of light emitted by the light emitting element 4A by approximately 90 ° at a position directly above the light emitting element 4A, and optically connected to the light emitting element 4A. An internal waveguide 31 to be coupled is provided so as to extend from the mirror portion 33 to the front end surface 3 b of the mount substrate 3.

  The light emitting element 4A has a shape of a square plate that is flat in the vertical direction, emits light upward from the upper surface, and is mounted on the one surface 3a of the mount substrate 3 from the light emitting side. As the light emitting element 4A, a VCSEL (Vertical Cavity Surface Emitting Laser) which is a semiconductor laser is employed. The IC substrate 5A is a driver IC that drives the VCSEL, has a shape of a square plate that is flat in the vertical direction, and is disposed in the vicinity of the light emitting element 4A. The light emitting element 4A and the IC substrate 5A are connected to the wiring pattern 36 of the mount substrate 3 by bumps 11 (see FIG. 3) made of gold or solder. In addition, although LED etc. are employable as 4 A of light emitting elements, LED etc. are difficult to oscillate at high speed compared with laser diodes, such as VCSEL, and use in the transmission band below several hundred MHz is a condition, and in that case Is advantageous in terms of low price.

  The mount substrate 3 needs to be rigid in order to avoid the influence of heat during mounting and the influence of stress due to the use environment. Further, in the case of optical transmission, since optical transmission efficiency from the light emitting element to the light receiving element is required, it is necessary to mount the optical element with high accuracy and to suppress position fluctuation due to the influence of heat during use as much as possible. For this reason, a silicon substrate is employed as the mount substrate 3. The mount substrate 3 is preferably made of a material having a linear expansion coefficient close to that of the light emitting element 4A. In addition to silicon, the mount substrate 3 is made of a compound semiconductor such as GaAs of the same system as the VCSEL material or a ceramic such as aluminum nitride. May be.

  The mirror part 33 can be formed by depositing gold, silver, copper or aluminum on a 45 ° inclined surface formed by etching the mount substrate 3 by a method such as vapor deposition or sputtering. The 45 ° inclined surface can be formed by anisotropic etching utilizing the difference in the etching rate of silicon crystals. For the anisotropic etching, for example, a strong alkali such as a potassium hydroxide aqueous solution or a TMAH (tetramethylammonium hydroxide) aqueous solution is used.

  The internal waveguide 31 is provided along one surface 3 a of the mount substrate 3, and transmits light emitted from the light emitting element 4 </ b> A in a direction parallel to the one surface 3 a of the mount substrate 3. The internal waveguide 31 is composed of two types of resins having different refractive indexes. Specifically, as shown in FIG. 3, the internal waveguide 31 includes a core 31a made of a resin having a high refractive index and a clad 31b made of a low refractive index resin that covers the core 31a from the periphery. These are disposed in a waveguide forming groove 32 formed in the mount substrate 3. The sizes of the core 31a and the clad 31b are determined from light loss calculation based on the divergence angle of the light emitting element 4A and the light receiving diameter of the light receiving element 4B described later. In addition to the resin, the internal waveguide 31 may be made of an inorganic material as long as it is a light transmissive material such as quartz.

  The waveguide forming groove 32 can be formed by anisotropic etching as in the case of forming the 45 ° inclined surface. In addition to anisotropic etching, there is a dry etching forming method such as reactive ion etching for forming the waveguide forming groove 32.

  As shown in FIGS. 4 and 5A and 5B, when the waveguide forming groove 32 having a substantially rectangular cross section and the 45 ° inclined surface are formed by anisotropic etching, the etching conditions are different. That is, the composition of the etching solution is different. Therefore, it is necessary to perform etching in two steps. However, either may be performed first.

  Alternatively, when the waveguide forming groove 32 is formed simultaneously with the 45 ° inclined surface, as shown in FIGS. 5C and 5D, the waveguide forming groove 32 has a substantially trapezoidal cross section. The groove width of the waveguide forming groove 32 is increased. The waveguide forming groove 32 has no problem as long as it does not cover the bonding pad for the light emitting element 4A. Therefore, this is also possible.

  The external waveguide 9 is bonded to the front end surface 3b of the mount substrate 3 by an optical adhesive, and the internal waveguide 31 is optically coupled to the external waveguide 9 by this bonding. become. If the distance from the mirror portion 33 to the external waveguide 9 is short, there is a case where the loss is small even if light is simply propagated in the air. In this case, the internal waveguide 31 is omitted. The light may be directly incident on the external waveguide 9 from the mirror unit 33.

  As the external waveguide 9, it is more convenient to use a flexible film-like one in which the resin optical waveguide is thinned. That is, the film-like external waveguide 9 is excellent in flexibility, and there is no problem even if it is used for a bent portion of, for example, a mobile phone. Depending on the bending curvature, light loss may occur, but this can be reduced by increasing the refractive index difference between the core and the cladding. The external waveguide 9 may be a silica fiber or a plastic fiber other than the film-like one.

  The header 6 is detachable from a socket type electrical connector (hereinafter simply referred to as “socket”) 7 which is an external connector provided on the wiring board 2. The header 6 and the socket 7 can be interchanged with each other, the socket 7 is provided on the mount board 3, the header 6 is provided on the wiring board 2, and the header 6 may be an external connector.

  As shown in FIG. 6A, the socket 7 has a substantially rectangular shape extending in the front-rear direction in a plan view. The socket 7 includes a socket main body 72 and a terminal 71 held by the socket main body 72. The socket main body 72 is provided with a fitting recess 72a having a rectangular frame shape in plan view. The terminal 71 is exposed in the fitting recess 72a. Further, the end portion of the terminal 71 protrudes from the socket main body 72 in the left-right direction, and this end portion is connected to a not-illustrated wiring pattern formed on the upper surface of the wiring substrate 2 by unillustrated solder or the like. The socket 7 is usually mounted on the wiring board 2 by reflow.

  On the other hand, as shown in FIG. 6B, the header 6 has a substantially rectangular shape extending in the front-rear direction that is slightly smaller than the socket 7 in a bottom view. The header 6 includes a header main body 62 and terminals 61 held by the header main body 62. The header main body 62 has a rectangular frame in bottom view that can be fitted into the fitting recess 72a of the socket 7. A fitting projection 62a is provided, and the terminal 61 is exposed on the surface of the fitting projection 62a. Further, the end portion of the terminal 61 protrudes in the left-right direction from the header body 62, and this end portion is connected to the wiring pattern 36 of the mount substrate 3 by the solder ball 10. Further, for mounting the header 6 on the mount substrate 3, it is possible to use terminal posts, pins, etc. in addition to the solder balls. The height including the mount substrate 3 and the solder ball 10 is about 1 mm.

  Then, when the fitting convex part 62a of the header 6 is inserted into the fitting concave part 72a of the socket 7 and they are fitted, the terminals 61 and 71 come into contact with each other and the wiring pattern of the wiring board 2 and the wiring pattern of the mount board 3 36 is electrically connected. At this time, the height from the lower surface of the socket 7 to the upper surface of the header 6 is about 1 mm. For this reason, the height from the upper surface of the wiring board 2 to the other surface 3c serving as the upper surface of the mount board 3 when the light emitting side photoelectric conversion part 1A1 is mounted on the wiring board 2 is about 2 mm.

  Since the basic configuration of the light-receiving side photoelectric conversion unit 1A2 is the same as that of the light-emitting side photoelectric conversion unit 1A1, detailed description thereof is omitted. The light-emitting side photoelectric conversion unit 1A1 is different from the light-emitting side photoelectric conversion unit 1A1 in that a light receiving element 4B that receives light on one surface 3a of the mount substrate 3 and converts an optical signal into an electric signal, as shown in FIG. An IC substrate 5B on which an IC circuit 50B for receiving an electrical signal from 4B is formed is mounted. PD is adopted as the light receiving element 4B, and the IC substrate 5B is a TIA (Trans-impedance Amplifier) element that performs current / voltage conversion. In addition, an amplifier element may be mounted on the mount substrate 3.

  In the photoelectric conversion apparatus 1A of the reference example as described above, the header 6 is provided on the one surface 3a of the mount substrate 3 on which the light emitting element 4A or the light receiving element 4B is mounted, and the internal waveguide 31 is connected to one of the mount substrates 3. Since it is provided so as to extend in a direction parallel to the direction 3a, the height of the entire device in the plate thickness direction of the mount substrate 3 can be suppressed, and the height of the device can be reduced.

  Next, with reference to FIG. 8 and FIG. 9, the photoelectric conversion apparatus 1B according to the first embodiment of the present invention will be described. Since this photoelectric conversion apparatus 1B is an improvement of the photoelectric conversion apparatus 1A of the reference example, the same components as those of the reference example are denoted by the same reference numerals, and description thereof is omitted. Also in this photoelectric conversion device 1B, the light receiving side photoelectric conversion unit is the same as the light emission side photoelectric conversion unit, and therefore only the light emission side photoelectric conversion unit 1B1 will be illustrated and described.

  In the light emission side photoelectric conversion unit 1B1 of the first embodiment, as shown in FIG. 8, an interposer substrate made of the same silicon resin as the mount substrate 3 is interposed between the mount substrate 3 made of silicon resin and the header 6. An intermediate substrate) 8 is provided. That is, the linear expansion coefficient of the mount substrate 3 and the linear expansion coefficient of the interposer substrate 8 are substantially equal. The upper surface of the interposer substrate 8 is connected to one surface 3 a of the mount substrate 3 by solder balls 15, and the header 6 is connected to the lower surface of the interposer substrate 8 by solder 110. As a result, the mount substrate 3 and the header 6 are electrically connected by the interposer substrate 8, the solder 110 and the solder balls 15.

  Details will be described below.

  As shown in FIG. 9A, the one surface 3a of the mount substrate 3 includes an external electrical connection terminal portion 36a, a wiring portion 36b, and terminal portions 36c for the light emitting element 4A and the IC substrate 5A. A wiring pattern 36 is formed.

  As shown in FIG. 8, the interposer substrate 8 is provided with a through wiring 80 that vertically penetrates the interposer substrate 8. The through wiring 80 is provided at a position corresponding to the external electrical connection terminal portion 36 a on the mount substrate 3, and is electrically connected to the external electrical connection terminal portion 36 a via the solder ball 15. It has become.

  Further, as shown in FIG. 9B, a wiring pattern 81 electrically connected to the through wiring 80 is formed on the surface (lower surface) on the header 6 side of the interposer substrate 8. The wiring pattern 81 has an electrode 81 a corresponding to the terminal 61 of the header 6. Thus, the mount substrate 3 and the header 6 are electrically connected via the interposer substrate 8 while changing the electrode pattern by changing the electrode pitch with the interposer substrate 8.

  As described above, by using the interposer substrate 8, the degree of freedom of the wiring pattern of the mount substrate 3 can be improved. That is, since the light emitting element 4 </ b> A and the IC substrate 5 </ b> A are mounted on the mount substrate 3, it is difficult to match the external electrical connection terminal portion 36 a of the wiring pattern 36 of the mount substrate 3 with the terminal 61 of the header 6. In such a case, the interposer substrate 8 is particularly effective.

  In the first embodiment, since the linear expansion coefficient of the interposer substrate 8 is substantially equal to the linear expansion coefficient of the mount substrate 3, even if the number of constituent members of the apparatus increases by providing the interposer substrate 8, the temperature changes. Therefore, the apparatus is not easily deformed. Thereby, even when the interposer substrate 8 is provided, deformation of the apparatus can be suppressed.

  Further, by forming the interposer substrate 8 from silicon resin, the wiring pattern 81 corresponding to the terminal 61 of the header 6 can be easily formed on the surface of the interposer substrate 8 facing the header 6. Further, since the mount substrate 3 and the interposer substrate 8 can be manufactured consistently at the wafer level by the silicon process in the manufacturing process of the device, the manufacturing cost can be kept low.

  Next, with reference to FIG. 10 and FIG. 11, the photoelectric conversion apparatus 1C according to the second embodiment of the present invention will be described. Since this photoelectric conversion apparatus 1C is also an improvement of the photoelectric conversion apparatus 1A of the reference example, the same reference numerals are given to the same components as those of the reference example, and description thereof will be omitted. Also in this photoelectric conversion device 1C, since the light receiving side photoelectric conversion unit is the same as the light emission side photoelectric conversion unit, only the light emission side photoelectric conversion unit 1C1 is illustrated and described.

  In the light emission side photoelectric conversion unit 1C1 of the second embodiment, an interposer substrate 108 made of silicon resin having a different configuration from the interposer substrate 8 of the first embodiment is provided between the mount substrate 3 and the header 6. Yes.

  As shown in FIG. 10, the interposer substrate 108 is disposed so as to be in surface contact with one surface 3 a of the mount substrate 3. In other words, the interposer substrate 108 of the second embodiment has a recess 108 a that can accommodate the light emitting element 4 </ b> A and the IC substrate 5 </ b> A on the mount substrate 3 on the surface facing the mount substrate 3 of the interposer substrate 108. The periphery of the recess 108 a is a contact portion 108 b that contacts the mount substrate 3.

  Further, the interposer substrate 108 is provided with a through wiring 180 that vertically penetrates the contact portion 108b of the interposer substrate 108. The through wiring 180 is provided at a position corresponding to the external electrical connection terminal portion 36a (see FIG. 11A) on the mount substrate 3, and is directly electrically connected to the external electrical connection terminal portion 36a. It has come to be.

  Further, as shown in FIG. 11B, a wiring pattern 181 electrically connected to the through wiring 180 is formed on the surface of the interposer substrate 108 on the header 6 side. The wiring pattern 181 has an electrode 181 a corresponding to the terminal 61 of the header 6. Thus, the mount substrate 3 and the header 6 are electrically connected via the interposer substrate 108 while changing the electrode pattern by changing the electrode pitch with the interposer substrate 108. Therefore, in the second embodiment, solder balls are not used as means for electrically connecting the mount substrate 3 and the interposer substrate 8.

  In the interposer substrate 108 of the second embodiment, unlike the interposer substrate 8 of the first embodiment, the interposer substrate 108 is disposed closer to the mount substrate 3 by accommodating the light emitting element 4A and the IC substrate 5A in the recess 108a. As a result, the interposer substrate 108 can be directly connected to the mount substrate 3 and the height of the apparatus can be reduced.

  In the second embodiment, the interposer substrate 108 forms a substantially sealed space H together with the mount substrate 3, and the light emitting element 4 </ b> A and the IC substrate 5 </ b> A are sealed in the space H. The space H may be filled with sealing resin, gas, or the like.

  In the case of the second embodiment, the interposer substrate 108 is provided with the recess 108a that accommodates the light emitting element 4A and the IC substrate 5A, and the interposer substrate 108 is mounted by the through wiring 180 provided in the contact portion 108b around the recess 108a. By directly electrically connecting to 3, solder balls that serve to electrically connect both substrates 3, 108 become unnecessary, thereby reducing the number of members and the height of the apparatus. In this case, the bonding reliability between the substrates 3 and 108 can be improved by directly connecting the mount substrate 3 and the interposer substrate 108 without using solder balls or the like.

  Further, since the light emitting element 4A and the IC substrate 5A are accommodated in the recess 108a, the light emitting element 4A and the IC substrate 5A can be sealed by the mount substrate 3 and the interposer substrate 108 to be protected from moisture, dust, and the like.

  In addition, by forming the interposer substrate 108 from silicon resin, the recess 108a can be formed at low cost and with high accuracy using a technique such as anisotropic etching.

  In the present embodiment, as the photoelectric conversion device 1B, a one-way communication type in which an optical signal is transmitted from the light emission side photoelectric conversion unit 1B1 to the light reception side photoelectric conversion unit is shown. A bidirectional communication type in which the light receiving element 4B is mounted on the light emitting side photoelectric conversion unit 1B1, the light emitting element 4A is mounted on the light receiving side photoelectric conversion unit, and a plurality of waveguides 31 are formed on the mount substrate 3. There may be. Moreover, the photoelectric conversion apparatus 1B should just be equipped with at least one of the light emission side photoelectric conversion part 1B1 or the light reception side photoelectric conversion part. Further, in both the one-way communication type and the two-way communication type, one-channel communication has been described. However, multi-channel communication may be performed by mounting an array-shaped light emitting / receiving element. Alternatively, a structure in which a plurality of waveguides are formed may be used.

  In the above embodiment, the interposer substrates 8 and 108 are formed of silicon resin. However, the present invention is not limited to this, and the interposer substrates 8 and 108 may be formed of glass or ceramics. When the interposer substrates 8 and 108 are made of glass, the heat dissipation performance against heat generated in the light emitting element 4A and the IC substrate 5A can be improved. Further, when the interposer substrates 8 and 108 are formed of ceramics, the high frequency characteristics can be improved.

It is a schematic block diagram of the photoelectric conversion apparatus of a reference example, and the wiring board to which this photoelectric conversion apparatus is connected. It is the figure which decomposed | disassembled the light emission side photoelectric conversion part of the photoelectric conversion apparatus of a reference example. (A) is a side view of a mount substrate on which an optical element is mounted, and (b) is a cross-sectional view taken along line AA of (a). It is the perspective view which looked at the mount board | substrate of the state before providing a waveguide from the downward direction. (A) is a bottom view of the mount substrate, (b) is a cross-sectional view of (a), (c) is a bottom view of the mount substrate of a modified example, and (d) is a cross-sectional view of (c). (A) is a perspective view of a socket type electrical connector, (b) is a perspective view of a header type electrical connector. It is the figure which decomposed | disassembled the light-receiving side photoelectric conversion part of the photoelectric conversion apparatus of a reference example. It is a schematic sectional drawing of the photoelectric conversion apparatus which concerns on 1st Embodiment of this invention. 1 is a photoelectric conversion device according to a first embodiment of the present invention, in which (a) is a bottom view of a mount substrate and (b) is a bottom view of an interposer substrate. It is a schematic sectional drawing of the photoelectric conversion apparatus which concerns on 2nd Embodiment of this invention. It is the photoelectric conversion apparatus which concerns on 2nd Embodiment of this invention, (a) is a bottom view of a mount board | substrate, (b) is a bottom view of an interposer board | substrate.

Explanation of symbols

1B, 1C Photoelectric conversion device 2 Wiring board 3 Mount board 3a One side 3c The other side 31 Internal waveguide 4A Light emitting element 4B Light receiving element 5A, 5B IC board 50A, 50B IC circuit 6 Header type electric connector 7 Socket type electric connector 8 , 108 Interposer substrate 80, 180 Through wiring 9 External waveguide 108a Recessed portion 108b Contact portion

Claims (3)

An optical element that converts an electrical signal into an optical signal or an optical signal into an electrical signal, an IC circuit for transmitting an electrical signal to or receiving an electrical signal from the optical element, and the optical element are mounted A mounting board; an electrical connector that can be attached to and detached from an external connector; and a waveguide that is optically coupled to the optical element. The electrical connector is mounted with the optical element and the IC circuit on the mounting board. A photoelectric conversion device provided on the mount substrate so as to be along one surface or the other surface of the mount substrate;
Between the mount substrate and the electrical connector, an intermediate substrate for changing the electrode pattern is provided,
The photoelectric conversion device, wherein the intermediate substrate is formed of a material having a linear expansion coefficient substantially equal to that of the mount substrate. The intermediate substrate is provided in surface contact with one surface of the mount substrate;
A concave portion capable of accommodating the optical element and the IC circuit on the mount substrate is provided on a surface of the intermediate substrate facing the mount substrate.
2. The photoelectric conversion apparatus according to claim 1, wherein a through-wiring that is in contact with the mount substrate and is electrically connected to the mount substrate is disposed around the concave portion of the intermediate substrate. The mount substrate is made of silicon,
3. The photoelectric conversion apparatus according to claim 1, wherein the intermediate substrate is made of a material selected from the group consisting of silicon, glass, and ceramics.

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