JP5457656B2 - Photoelectric conversion device - Google Patents

Description

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

Conventionally, as a photoelectric conversion device, a light emitting element that emits light by converting an electric signal into an optical signal and an IC circuit (signal processing unit) for transmitting the electric signal to the light emitting element are formed, and the light emitting element emits light. A substrate mounted on one side from the side opposite to the side to be mounted is provided. In addition, there is known one provided with a waveguide that is disposed so as to extend from the light emitting element in a direction orthogonal to one surface of the substrate and that transmits light emitted from the light emitting element (see Patent Document 1). Hereinafter, the light emitting element and the light receiving element may be simply referred to as an optical element.
JP 2001-42170 A

  By the way, when an optical element and a signal processing unit (IC circuit or IC substrate) are mounted on the substrate, there is a problem that it is difficult to individually inspect the optical element and the signal processing unit.

  In addition, if either the optical element or the signal processing unit is defective, there is a problem that the entire substrate is lost.

  Furthermore, when the heat from the signal processing unit affects the light emission characteristics and the light receiving characteristics of the optical element, it is necessary to prevent the heat effects.

  In view of such circumstances, the present invention can individually inspect the optical element and the signal processing unit, and even if either one is defective, the entire substrate is not lost, and the heat from the signal processing unit An object of the present invention is to provide a photoelectric conversion apparatus in which the influence is not exerted on the optical element.

The present invention is the sub-mount substrate is mounted on one side of the upper surface of the mount substrate, the sub-mount substrate is a silicon substrate, the upper surface waveguide forming groove of the sub-mount substrate is formed, the waveguide An internal waveguide connected to the external waveguide is disposed in the formation groove, which includes a core that guides light and a clad that covers and holds the core from the periphery, and converts an electrical signal into an optical signal. An optical element that converts and emits light or receives light and converts an optical signal into an electrical signal is mounted on the submount substrate, and a position directly below the optical element in the waveguide formation groove of the submount substrate In addition, a mirror part for converting the optical path of light of the optical element by approximately 90 ° is formed, and the internal waveguide optically coupled to the optical element is formed to extend from the mirror part to the end face of the submount substrate. Is The signal processing unit for receiving electrical signals from or optical element to transmit an electrical signal to an optical element is mounted on the other side of the upper surface of the mounting substrate, the connector detachable external electrical contact terminal, the in the upper surface opposite the lower surface and the mounting substrate submount substrate and the signal processing unit is mounted, and that it is mounted or formed at a position substantially directly below the spans and the submount substrate and the signal processing unit A characteristic photoelectric conversion device is provided.

The electrical connection between the signal processing unit of the sub-mount substrate side and the mounting substrate side is preferably a wire bonding.

The electrical connection between the sub-mount substrate side and the mounting substrate side is preferably a surface-mounted.

On the submount substrate, it is preferable to form a fitting portion for aligning an external waveguide and the waveguide for optical coupling.

The submount substrate as an optical element, it is preferable to implement a light emitting element and a light receiving element.

The photoelectric conversion device includes a light emission side photoelectric conversion unit and a light reception side photoelectric conversion unit, and an external waveguide connecting the waveguides of both the parts is flexible, and the wiring pattern of the mount substrate of both parts Can be configured to be connected by a circuit pattern of a flexible substrate that transmits an electrical signal.

The flexible substrate may be configured to be connected to at least one of a surface on which the submount substrate of the mount substrate is mounted and an opposite surface thereof.

The flexible substrate may be connected by being sandwiched between two mount substrates formed in two layers.

The flexible substrate can also serve as a mount substrate.

  According to the present invention, the optical element is mounted on the submount substrate mounted on the mount substrate, and the signal processing unit and the connector are mounted on the mount substrate. Thereby, before mounting the submount substrate on the mount substrate, it becomes easy to individually inspect the signal processing unit of the mount substrate and the optical element of the submount substrate.

  Further, even if either the optical element or the signal processing unit is defective, only one of the mount substrate and the submount substrate is defective, so that the entire substrate is not lost.

  Further, since the optical element is mounted on the submount substrate instead of the mount substrate on which the signal processing unit is mounted, the thermal effect from the signal processing unit is less likely to affect the optical element, and the light emission characteristics are stabilized. .

Further, since the size of the submount substrate can be reduced, the number of silicon wafers and the like can be increased, and the cost can be reduced. Furthermore, if the internal waveguide and the mirror portion are formed in the waveguide forming groove of the submount substrate, the photoelectric conversion device can be made thinner.

Also, the submount substrate is mounted on one side of the upper surface of the mount substrate, the signal processing unit is mounted on the other side of the upper surface of the mount substrate, and straddles the submount substrate and the signal processing unit on the lower surface of the mount substrate. Since the connector is mounted or formed at a position almost directly below, both surfaces of the mounting substrate can be used as a mounting surface or a forming surface, so that the mounting / forming area of the photoelectric conversion device can be reduced.

On the other hand, as the preferred form of the invention, the electrical connection between the sub-mount substrate side and the mounting substrate side comes to improving the reliability of wire bonding der lever, connected.

Further, electrical connection between the sub-mount substrate side and the mounting substrate side surface mount der lever, reliability comes to improve the connection. In addition, batch connection is possible by reflow or the like, and man-hours can be shortened.

In addition, if the fitting portion for alignment is formed , the optical coupling accuracy between the waveguide of the submount substrate and the external waveguide is improved.

Moreover, lever to implement a light emitting element as a light element and a light receiving element on the same sub-mount substrate, since the photoelectric converting device is bi-directional module, it can be reduced in size. In addition, the bidirectional module can be individually inspected.

In addition, when transmitting an optical signal and an electrical signal between the light emitting side photoelectric conversion unit and the light receiving side photoelectric conversion unit, an electrical signal electrical connector is provided separately from the optical signal optical connector (external waveguide). Was necessary. In contrast, the wiring pattern of the mounting substrate of both parts, lever connecting the circuit pattern of the flexible substrate for transmitting electrical signals, the electrical connector is not required. Moreover, since the flexible substrate and the external waveguide are flexible and flexible, the degree of freedom of wiring is increased. As a result, space saving, cost reduction, and mounting tact for electrical connectors are unnecessary.

Furthermore, if the flexible substrate is connected to the surface on which the submount substrate is mounted, the distance between the flexible substrate and the external waveguide is reduced, so that the flexibility between the flexible substrate and the external waveguide is improved. Further, if the flexible substrate is connected to both the surface on which the submount substrate is mounted and the opposite surface, the flexible substrate has two layers, so that the number of electrical wirings can be increased.

In addition, if the flexible substrate is sandwiched and connected between the two layers of the mount substrate, both sides of the mount substrate become rigid. Therefore, compared to the case where either surface becomes the flexible substrate, components and wires Since the bond adhesion strength can be increased, mounting reliability is improved.

Furthermore, if the flexible substrate also serves as the mount substrate, the thickness of the mount substrate can be reduced to the same thickness as that of the flexible substrate, compared to the case where a rigid mount substrate is used.

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

  FIG. 1 shows a photoelectric conversion apparatus 1A according to the first embodiment of the present invention. This photoelectric conversion device 1A includes a light emitting side photoelectric conversion unit (E / O) mounted on one (left side in FIG. 1) wiring board 2 by fitting electrical connectors (hereinafter simply referred to as connectors) 6 and 7 together. 1A1 is also provided. In addition, a light-receiving side photoelectric conversion part (also referred to as an O / E module) 1A2 that is attached to the other (right side in FIG. 1) wiring board 2 by fitting the connectors 6 and 7 is provided. Furthermore, an external waveguide 9 that optically connects these conversion units 1A1 and 1A2 is provided.

  In this specification, the vertical direction in FIG. 1 is referred to as the vertical direction of the photoelectric conversion device 1A, the direction orthogonal to the paper surface in FIG. 1 is referred to as the horizontal direction of the photoelectric conversion device 1A, and the light emission side photoelectric conversion unit 1A1. On the other hand, the right side of FIG. 1 is referred to as the front and the left side is referred to as the rear, and the left side of FIG.

  As shown also in FIG. 6, the light emission side photoelectric conversion part 1A1 is provided with the mount board | substrate 3 which makes the rectangular shape extended in the front-back direction by planar view.

  The lower surface of the submount substrate 12 is mounted on the front side of the upper surface 3c of the mount substrate 3 by bonding or the like. On the upper surface of the submount substrate 12, a light emitting element 4A that emits light by converting an electrical signal into an optical signal is mounted, and an internal waveguide 31 that is optically coupled to the light emitting element 4A is formed.

  On the upper surface of the submount substrate 12, a mirror portion 33 that converts the optical path of the light emitted by the light emitting element 4 </ b> A by approximately 90 ° is formed at a position directly below the light emitting element 4 </ b> A. The internal waveguide 31 that is optically coupled to the light emitting element 4 </ b> A is formed to extend from the mirror portion 33 to the front end surface of the submount substrate 12.

  Further, an IC substrate (signal processing unit) 5 on which an IC circuit for transmitting an electric signal to the light emitting element 4A is formed is mounted on the rear side portion of the upper surface 3c of the mount substrate 3.

A connector 6 is mounted on the lower surface 3 a of the mount substrate 3. As is clear from FIG. 1, the connector 6 is mounted on the lower surface 3 a of the mount substrate 3 and at a position almost directly below the submount substrate 12 and the IC substrate (signal processing unit) 5.

  On the upper surface 3c of the mount substrate 3, wiring patterns 36 such as a driving power line and a signal line for the light emitting element 4A are formed.

  As the light emitting element 4A, a VCSEL (Vertical Cavity Surface Emitting Laser) that is a semiconductor laser is employed. In addition, LED etc. are employable as the light emitting element 4A. However, an LED or the like has no directivity and has a small ratio of optical coupling to the internal waveguide 31, so that it is necessary to have a margin of light efficiency. In this case, it is advantageous in terms of low cost.

  The IC substrate 5 is a driver IC that drives the VCSEL. The light emitting element 4A and the IC substrate 5 are connected to the wiring pattern 36 of the mount substrate 3 by a wire 13 such as gold (wire bonding). The wires 13 and the wiring pattern 36 are sealed with the sealing resin 14.

  The submount substrate 12 needs to have rigidity 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 submount substrate 12. The submount substrate 12 is preferably made of a material having a linear expansion coefficient close to that of the light emitting element 4A, and may be made of a compound semiconductor such as GaAs of the same system as the VCSEL material other than silicon. . Alternatively, a ceramic material such as aluminum nitride or silicon nitride may be used as a material having a good coefficient of linear expansion and thermal conductivity.

  The mirror part 33 can be formed by evaporating gold or aluminum on a 45 ° inclined surface formed by etching the submount substrate 12. The 45 ° inclined surface can be formed, for example, by anisotropic etching with a potassium hydroxide solution.

  The internal waveguide 31 is formed along the upper surface of the submount substrate 12, and transmits light emitted from the light emitting element 4 </ b> A in a direction parallel to the upper surface of the submount substrate 12. The internal waveguide 31 is composed of two types of resins having different refractive indexes.

  Specifically, the internal waveguide 31 includes a core that guides light and a clad that covers and holds the core from the periphery, and is used for forming a waveguide formed on the upper surface of the submount substrate 12. It is disposed in the groove. The core is made of a resin having a high refractive index, and the clad is made of a resin having a low refractive index. The sizes of the core and the clad 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 external waveguide 9 is bonded to the front end surface of the submount substrate 12 by an optical adhesive, and the internal waveguide 31 is optically coupled to the external waveguide 9 by this bonding. become. That is, the mirror portion 33 and the internal waveguide 31 constitute the waveguide of the present invention. In addition, if the distance from the mirror part 33 to the external waveguide 9 is short, there may be a small loss even if light is simply propagated in the air. In this case, the internal waveguide 31 may be omitted, and 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.

  Specifically, the junction between the front end face of the submount substrate 12 and the external waveguide 9 is such that the gap between the submount substrate 12 and the external waveguide 9 is 5 to 30 μm, and the gap is filled with an adhesive. This is done by curing the adhesive with ultraviolet rays. Alternatively, when the gap between the submount substrate 12 and the external waveguide 9 is set to about 100 μm, an adhesive is filled, and then the gap between the submount substrate 12 and the external waveguide 9 is reduced, thereby bonding. The agent can be filled without running out.

  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, and a detailed description thereof is omitted, but the light receiving element is denoted by reference numeral 4B.

  If the external waveguide 9 is joined to the light emitting side photoelectric conversion unit 1A1 and the light receiving side photoelectric conversion unit 1A2, as described above, the light emitting side photoelectric conversion unit 1A1 and the light receiving side photoelectric conversion unit 1A2 are optically coupled. Will be connected.

  In the photoelectric conversion apparatus 1A of the first embodiment, the light emitting element 4A is mounted on the upper surface of the submount substrate 12 mounted on the upper surface 3c of the mount substrate 3, and the IC substrate 5 is mounted on the upper surface 3c of the mount substrate 3. The connector 6 is mounted on the lower surface 3a.

  Thereby, before mounting the submount substrate 12 on the upper surface 3c of the mount substrate 3, the IC substrate 5 of the mount substrate 3 and the light emitting element 4A of the submount substrate 12 can be easily inspected individually.

  Further, even if either the light emitting element 4A or the IC substrate 5 is defective, only one of the mount substrate 3 and the submount substrate 12 becomes defective, so that the entire substrate is not lost.

  Furthermore, the light emitting element 4A is mounted on the submount substrate 12 instead of the mount substrate 3 on which the IC substrate 5 is mounted, and the mirror portion 33 and the internal waveguide 31 are formed. As a result, the heat effect from the IC substrate 5 does not easily reach the light emitting element 4A, and the light emission characteristics are stabilized.

  In addition, since the submount substrate 12 can be reduced in size, the number of parts taken from a silicon wafer or the like is increased, and the cost can be reduced.

Furthermore, by forming the internal waveguide 31 and the mirror portion 33 in the waveguide forming groove of the submount substrate 12, it is possible to reduce the thickness of the photoelectric conversion device.

In addition, by mounting the connector 6 on the lower surface 3a opposite to the upper surface 3c on which the submount substrate 12 of the mount substrate 3 is mounted, both surfaces of the mount substrate 3 can be used as mounting surfaces. The area can be reduced.

  Furthermore, since the electrical connection between the submount substrate 12 side and the mount substrate 3 side is wire bonding, the connection reliability is improved.

  FIG. 2 shows a photoelectric conversion apparatus 1B according to the second embodiment. The difference from the photoelectric conversion apparatus 1A of the first embodiment is that the IC substrate 5 is connected to the wiring pattern 36 of the mount substrate 3 by bumps 11 made of gold or solder. In this way, by connecting the IC substrate 5 to the wiring pattern 36 of the mount substrate 3 with the bumps 11 made of gold or solder, the high-frequency characteristics can be improved (impedance matching is easy).

  FIG. 3 shows a photoelectric conversion apparatus 1C according to the third embodiment. The difference from the photoelectric conversion apparatus 1A of the first embodiment is that the IC substrate 5 is connected to the wiring pattern 36 of the mount substrate 3 by bumps 11 made of gold or solder. Further, the submount substrate 12 is inverted upside down and connected to the wiring pattern 36 of the mount substrate 3 by bumps 11 made of gold or solder.

  Thus, by eliminating all wire bonding connections, the high frequency characteristics can be further improved. In addition, external noise can be prevented from being applied to the wire, and the noise characteristics can be improved. In addition, since the electrical connection between the submount substrate 12 side and the mount substrate 3 side is surface mounting, the connection reliability is improved.

  Fig.4 (a) is the photoelectric conversion apparatus 1D of 4th Embodiment. The difference from the photoelectric conversion apparatus 1A of the first embodiment is that a slot (connector) 18 having an electrical connection terminal 15 for inserting an SD card or the like 17 is inserted into the upper surface 3c of the mount substrate 3 in place of the connector 6. It is provided. Thereby, since the submount substrate 12 and the slot (connector) 18 are mounted on the upper surface (one surface) 3c of the mount substrate 3, the photoelectric conversion device can be thinned. As shown in FIG. 4B, the electrical connection terminals 15 can be provided on the upper surface 3 c of the mount substrate 3, and the slots (connectors) 18 can be provided on the mating substrate 50.

  FIG. 5 shows a photoelectric conversion apparatus 1E according to the fifth embodiment. The difference from the photoelectric conversion apparatus 1A of the first embodiment is that the submount substrate 12 and the IC substrate 5 of the mount substrate 3 are covered with the shield cover 19. Thereby, the influence with respect to external noise can be reduced by connecting the shield cover 19 with the ground of the mount substrate 3. Moreover, it can suppress releasing self-radiation noise outside.

  FIGS. 7A and 7B show the photoelectric conversion apparatus 1F of the sixth embodiment. The difference from the photoelectric conversion device 1A of the first embodiment is that the wiring pattern 36 of the mount substrate 3 of the light emission side photoelectric conversion unit 1A1 and the light reception side photoelectric conversion unit 1A2 is transmitted through the flexible substrate 22 that transmits an electrical signal. It is a point connected by the circuit pattern 22a.

  That is, when transmitting an optical signal and an electrical signal between the light emitting side photoelectric conversion unit 1A1 and the light receiving side photoelectric conversion unit 1A2, separately from the optical signal optical connector (external waveguide 9), FIG. Although not specifically illustrated, an electrical connector for electrical signals is required. That is, for power supply, ground wiring, feedback control for stable operation of optical signal transmission, and the like.

  On the other hand, in the photoelectric conversion apparatus 1F of the sixth embodiment, it is assumed that the external waveguide 9 is flexible. And the wiring pattern 36 of the mount board 3 of the photoelectric conversion parts 1A1, 1A2 on the light emitting side and the light receiving side is connected by the circuit pattern 22a of the flexible board 22. The circuit patterns 22a and 22f are hatched for easy understanding.

  Specifically, the end portions 22b and 22c of the flexible substrate 22 of the light-emitting side and the light-receiving side photoelectric conversion units 1A1 and 1A2 are formed in the same outer shape as the mounting substrate 3 on that side. Connected to the bottom.

  Further, in FIG. 7B, the circuit pattern 22a of the flexible substrate 22 is formed by connecting the wiring pattern 36 of the mount substrate 3 of the photoelectric conversion units 1A1 and 1A2 on the light emitting side and the light receiving side with two circuit patterns 22a. ing. Note that the number of circuit patterns 22a is two for simplification, but the number is not limited to two.

  Further, the end portions 22d and 22e of the circuit pattern 22a of the flexible substrate 22 of the photoelectric conversion portions 1A1 and 1A2 on the light emitting side and the light receiving side are connected to the terminals 6a of the respective electrical connectors 6. A large number of circuit patterns 22 f are separately formed on the flexible substrate 22, and each circuit pattern 22 f is connected to an appropriate terminal of each electrical connector 6. Reference numeral 22g denotes a through hole, which is connected to the ground circuit pattern 22f of the flexible substrate 22 by inserting a leg portion or the like of the shield cover 19 of the fifth embodiment.

  Further, the circuit patterns 22 a and 22 f of the flexible substrate 22 may be connected to circuits and components such as the mount substrate 3, the submount substrate 12, and the IC substrate 5.

  In the photoelectric conversion device 1F of the sixth embodiment, the wiring pattern 36 of the mount substrate 3 of the photoelectric conversion units 1A1 and 1A2 on the light emitting side and the light receiving side is replaced with the circuit pattern 22a of the flexible substrate 22 that transmits an electrical signal. By connecting, an electrical connector becomes unnecessary.

  Moreover, since the flexible substrate 22 and the external waveguide 9 are flexible and flexible, the degree of freedom of wiring is increased. As a result, space saving, cost reduction, and mounting tact for electrical connectors are unnecessary.

  7A and 7B, the flexible substrate 22 is connected to the lower surface of the mount substrate 3, but the flexible substrate 22 can be connected to the upper surface of the mount substrate 3 as shown in FIG. 8A.

  In this way, since the flexible substrate 22 can be connected to the upper surface of the mount substrate 3 on which the submount substrate 12 is mounted, the interval t between the flexible substrate 22 and the external waveguide 9 is narrowed. Flexibility with the waveguide 9 is improved.

  Further, as shown in FIG. 8B, the flexible substrate 22 can be connected to both the upper surface and the lower surface of the mount substrate 3.

  In this way, since the flexible substrate 22 has two layers, the number of electrical wirings can be increased.

  Further, as shown in FIG. 8C, the flexible substrate 22 can be connected by being sandwiched between the mount substrates 3 (3d, 3e) formed in two layers.

  In this case, since both surfaces of the mount substrate 3 (3d, 3e) are rigid, compared to the case where either surface is the flexible substrate 22 (see FIGS. 8A and 8B), the component In addition, since the adhesion strength of the wire bond can be increased, mounting reliability is improved.

  Furthermore, as shown in FIG. 8D, the flexible substrate 22 can also be used as the mount substrate 3. That is, the rigid mount substrate 3 is omitted, and the end portions 22b and 22c of the flexible substrate 22 are used as the mount substrate 3 '.

  In this way, the thickness of the mount substrate 3 ′ can be reduced to the same thickness as that of the flexible substrate 22 as compared with the case where the mount substrate 3 is rigid.

  In each of the above embodiments, it is preferable to form a fitting shape that aligns the optical waveguide 31 and the external waveguide 9 of the submount substrate 12 for optical coupling.

  That is, as shown in FIG. 9B, the upper surface of the submount substrate 12 has substantially trapezoidal (gradient-shaped) fitting recesses 12a and 12b at left and right positions around the core 31a of the internal waveguide 31. Are formed respectively. Illustration of the cladding is omitted.

  Further, as shown in FIG. 9A, on the lower surface of the external waveguide 9, there is a substantial base that can be fitted in the fitting recesses 12a and 12b of the submount substrate 12 at the left and right positions around the core 9a. Shaped (gradient-shaped) fitting projections 9b and 9c are formed, respectively. Illustration of the cladding is omitted.

  Then, as shown in FIG. 10, the fitting convex portions 9 b and 9 c of the external waveguide 9 are fitted into the fitting concave portions 12 a and 12 b of the submount substrate 12, respectively.

  Thereby, the axis center can be aligned so that the core 31a of the internal waveguide 31 of the submount substrate 12 and the core 9a of the external waveguide 9 do not shift in the left-right direction (width direction). As a result, the optical coupling accuracy between the internal waveguide 31 and the external waveguide 9 of the submount substrate 12 is improved.

  In each of the above embodiments, the light emitting element 4A is mounted on the submount substrate 12, the internal waveguide 31 that is optically coupled to the light emitting element 4A is formed, and an electrical signal is transmitted to the light emitting element 4A on the mount substrate 3. It was a unidirectional module which mounted IC board (Drv-IC) 5 in which the IC circuit for it was formed.

  On the other hand, as shown in FIG. 11A, the light-emitting element (VCSEL) 4A and the light-receiving element (PD) 4B are mounted on the submount substrate 12, and the internal conductor optically coupled to the light-emitting element 4A. Apart from the waveguide 31, an internal waveguide 40 that is optically coupled to the light receiving element 4B is formed.

  In addition to the light-emitting side external waveguide 9, a light-receiving side external waveguide 41 that is optically coupled to the internal waveguide 40 is provided.

  Furthermore, an IC substrate (TIA: transimpedance amplifier) 42 on which an IC circuit for receiving an electrical signal from the light receiving element 4B is formed on the mount substrate 3 separately from the IC substrate (Drv-IC) 5. Is implemented.

  By mounting the light emitting element 4A and the light receiving element 4B on the same submount substrate 12 in this way, the photoelectric conversion device becomes a bidirectional module, so that the size can be reduced. In addition, the bidirectional module can be individually inspected. As shown in FIG. 11B, an IC substrate (Drv + TIA) 43 in which the IC substrates 5 and 42 are integrated may be used.

  Further, as shown in FIG. 12A corresponding to FIG. 11A and FIG. 12B corresponding to FIG. 11B, the external waveguides 9 and 41 are integrated (2ch). An external waveguide 44 can also be used.

  If the integrated IC substrate (Drv + TIA) 43 and the external waveguide 44 are provided in this way, the size can be reduced.

It is a schematic block diagram of the photoelectric conversion apparatus which concerns on 1st Embodiment of this invention, and the wiring board to which this photoelectric conversion apparatus is connected. It is a principal part cross-sectional side view of the light emission side photoelectric conversion part of the photoelectric conversion apparatus of 2nd Embodiment of this invention. It is a principal part cross-sectional side view of the light emission side photoelectric conversion part of the photoelectric conversion apparatus of 3rd Embodiment of this invention. (A) and (b) are the principal part cross-sectional side views of the light emission side photoelectric conversion part of the photoelectric conversion apparatus of 4th Embodiment of this invention. It is a principal part cross-sectional side view of the light emission side photoelectric conversion part of the photoelectric conversion apparatus of 5th Embodiment of this invention. It is a top view of the light emission side photoelectric conversion part which concerns on 1st Embodiment. It is the photoelectric conversion apparatus which concerns on 6th Embodiment of this invention, (a) is a side view, (b) is a bottom view. (A)-(d) is a side view of the modification of the photoelectric conversion apparatus which concerns on 6th Embodiment of this invention. (A) is a perspective view of the fitting shape of an external waveguide, (b) is a perspective view of the fitting shape of a submount substrate. FIG. 10 is a plan view of a fitting state of the external waveguide and the submount substrate in FIG. 9. (A) (b) is a top view of the light emission side photoelectric conversion part made into the bidirectional | two-way module with the external waveguide of 1ch, respectively. (A) (b) is a top view of the light emission side photoelectric conversion part made into the bidirectional | two-way module with the external waveguide of 2ch, respectively.

Explanation of symbols

1A to 1F Photoelectric conversion device 1A1 Light emission side photoelectric conversion unit 1A2 Light reception side photoelectric conversion unit 2 Wiring substrate 3 Mount substrate 3a Lower surface 3c Upper surface 31 Internal waveguide (waveguide)
33 Mirror part 36 Wiring pattern 4A Light emitting element (optical element)
4B Light receiving element (optical element)
5 IC board (signal processing part)
6 Electrical connector 7 Electrical connector 9 External waveguide 12 Submount substrate 22 Flexible substrate

Claims (9)

Submount substrate is mounted on one side of the upper surface of the mount substrate,
The submount substrate is a silicon substrate, and a waveguide forming groove is formed on the upper surface of the submount substrate. In the waveguide forming groove, a core that guides light, and the core is covered from the periphery. An internal waveguide that is connected to an external waveguide,
An optical element that converts an electrical signal into an optical signal to emit light or receives and converts an optical signal into an electrical signal is mounted on the submount substrate,
A mirror part for converting the optical path of the light of the optical element by approximately 90 ° is formed at a position directly below the optical element in the waveguide forming groove of the submount substrate, and is optically coupled to the optical element. The internal waveguide is formed to extend from the mirror portion to an end surface of the submount substrate,
The signal processing unit for receiving electrical signals from or optical element to transmit an electrical signal to an optical element is mounted on the other side of the upper surface of the mounting substrate,
Connector detachable external electrical contact terminal, by the upper surface opposite the lower surface and the sub-mount substrate and the signal processing unit is mounted in the mounting substrate, and span and the submount substrate and the signal processing unit A photoelectric conversion device, characterized in that it is mounted or formed at a position almost directly below .   2. The photoelectric conversion apparatus according to claim 1, wherein the electrical connection between the submount substrate side and the mount substrate side is wire bonding.   The photoelectric conversion apparatus according to claim 1, wherein the electrical connection between the submount substrate side and the mount substrate side is surface mounting. The photoelectric conversion apparatus according to claim 1 , wherein a fitting portion for aligning the external waveguide and the waveguide for optical coupling is formed on the submount substrate. The submount substrate as an optical element, photoelectric conversion device according to any one of claims 1 to 4, characterized in that it implements a light emitting element and a light receiving element. As the photoelectric conversion device, a light emitting side photoelectric conversion unit and a light receiving side photoelectric conversion unit are provided, and an external waveguide connecting the waveguides of both the parts is flexible,
2. The photoelectric conversion apparatus according to claim 1 , wherein the wiring patterns of the mounting boards in both parts are connected by a circuit pattern of a flexible board that transmits an electrical signal. The photoelectric conversion apparatus according to claim 6 , wherein the flexible substrate is connected to at least one of a surface on which the submount substrate of the mount substrate is mounted and an opposite surface thereof. 7. The photoelectric conversion apparatus according to claim 6 , wherein the flexible substrate is sandwiched and connected between mount substrates formed in two layers. The photoelectric conversion apparatus according to claim 6 , wherein the flexible substrate also serves as a mount substrate.

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