JP2017167261A - Optical wiring mounting structure, optical module, and optical wiring mounting method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a compact optical wiring mounting structure that realizes highly efficient optical coupling.SOLUTION: The optical wiring mounting structure includes an optical path converter 30 arranged in an optical device 10 having an optical input/output unit for entering and emitting light upward of a substrate surface; and an optical fiber fitting member 40 having a support plate 45 on which an optical fiber 21 is placed, for holding the optical fiber 21 inside the optical path converter 30. The optical path converter 30 has an optical fiber guide for guiding the optical fiber 21, and a lens 35 formed on the inner wall of the optical fiber guide, at least a portion of the support plate 45 being inserted into the optical fiber guide, the optical fiber 21 being held at a position where the end face of the optical fiber 21 matches the focus point of the lens 35.SELECTED DRAWING: Figure 5

Description

  The present invention relates to an optical wiring mounting structure, an optical module, and an optical wiring mounting method.

  In data communication between LSI chips in a server or supercomputer, electrical signal transmission is performed by electrical wiring. In broadband signal transmission, transmission becomes more difficult as the distance increases, due to loss in electrical wiring and waveform degradation due to crosstalk. Therefore, an optical interconnect that converts an electrical signal into an optical signal and connects LSI chips with an optical wiring is drawing attention. In the future, high-speed electrical wiring is expected to be limited to the wiring distance on the package.

  As a form of the optical interconnect, a structure in which an optical transceiver in the form of a chip, which is a minute photoelectric conversion component, is arranged in the immediate vicinity of the LSI is desirable. A technique called silicon photonics has been developed as a technique for realizing a chip-shaped micro-optical transceiver. This is a technique for forming an element having a minute light control function on a silicon substrate by a CMOS process. Elements having a light control function include an optical modulator, a photodetector, and the like, and a thin wire waveguide connecting them has already been realized. In order to connect the thin waveguide to an optical fiber as an external optical wiring, several methods for forming an optical interface on a chip have been developed.

  As an example of the optical interface, a diffraction grating formed in a waveguide layer by silicon photonics technology is used. An optical fiber serving as an external optical wiring is held in accordance with the diffraction angle of the diffraction grating using a fiber holder, and is directly connected to the diffraction grating on the optical wiring substrate (see, for example, Patent Document 1).

JP2013-243649A

  In the conventional optical fiber connection structure shown in FIG. 1, the optical fiber 121 held by the optical connector 108 is aligned with the light input / output position of the diffraction grating 115 from the vertical direction of the optical wiring board 112 with high accuracy. The angle and position are adjusted with high accuracy while standing the optical connector 108 on the optical wiring substrate 112 in accordance with the light emission angle of the diffraction grating 115, and the optical fiber 121 and the optical waveguide 114 are optically connected. In this configuration, in addition to the difficulty of position adjustment, it is difficult to realize a compact and stable low-profile mounting.

  Therefore, it is an object to provide a compact optical wiring mounting structure that realizes high-efficiency optical coupling and an optical module using the same.

In one aspect, the optical wiring mounting structure is:
An optical path changer disposed in an optical device having a light input / output unit for entering and exiting light upward with respect to the substrate surface;
An optical fiber mounting member for holding an optical fiber and holding the optical fiber in the optical path converter;
Have
The optical path changer has an optical fiber guide for guiding the optical fiber, and a lens formed on an inner wall of the optical fiber guide,
At least a part of the support plate is inserted into the optical fiber guide to hold the optical fiber at a position where the end face of the optical fiber coincides with the focal point of the lens.

  As one aspect, highly efficient optical coupling is realized by a compact optical wiring mounting structure.

It is a figure which shows the mounting structure of the conventional optical fiber. It is a trihedral view showing a schematic configuration of an optical device to which the optical wiring mounting structure of the embodiment is applied. It is a three-view figure which shows schematic structure of the optical path changer used with the optical wiring mounting structure of embodiment. It is a figure explaining the mounting state of the optical fiber to the optical path changer of FIG. It is a three-view figure of the optical wiring mounting structure of embodiment. It is a figure which shows the aspect of the optical connection in the optical wiring mounting structure of FIG. It is a three-view figure of the fiber attachment member used with the optical wiring mounting structure of embodiment. It is a three-plane figure which shows the mounting state of the optical fiber to an optical fiber attachment member. It is a figure which shows the connection sequence of an optical fiber mounting structure. It is a figure of the optical wiring mounting structure using the modification of an optical fiber attachment member. It is a figure of the optical wiring mounting structure using another modification of an optical fiber attachment member. It is a figure of the modification of an optical path changer. It is the schematic of the optical module of embodiment. It is a figure which shows an example of the system board in which an optical module is used.

  FIG. 2 is a three-view diagram illustrating a schematic configuration of the optical device 10 to which the optical wiring mounting structure of the embodiment is applied. 2A is a top view in the XY plane, FIG. 2B is a front view seen from the X direction, and FIG. 2C is a cross-sectional view taken along the line AA ′ of FIG. .

  The optical device 10 includes an optical waveguide 14 formed on the optical wiring substrate 12 and a diffraction grating 15 formed at the tip of the optical waveguide 14. The optical waveguide 14 is connected to an optical circuit including an optical modulator and a photodetector on the opposite side of the diffraction grating 15, but these optical circuits are omitted in FIG.

  The diffraction grating 15 functions as an optical interface or an optical input / output unit, and inputs / outputs light in a direction substantially perpendicular to the surface of the optical wiring board 12. External optical wiring such as an optical fiber is introduced into the end face 12 e side of the optical wiring board 12, and is aligned and mounted with respect to the optical waveguide 14. By using the diffraction grating 15 as an optical interface between the optical waveguide 14 and the external optical wiring, the optical waveguide 14 can be inspected using actual light during the wafer manufacturing process. Since chip defects are known during wafer manufacturing, it is possible to simplify the determination of process conditions and to exclude defective products at the previous process stage.

The optical waveguide 14 and the diffraction grating 15 may be covered with a protective film 19. The protective film 19 is formed of a transparent material such as SiO ₂ or SiON. For example, a SiO ₂ film is formed on the entire surface of the optical wiring substrate 12 by sputtering or the like, and the surface is planarized by CMP (Chemical Mechanical Polishing) or the like. An optical wiring mounting structure, which will be described later, is disposed on the protective film 19 at a position where optical coupling between the diffraction grating 15 and the external optical wiring is realized.

  FIG. 3 is a three-view diagram showing the configuration of the optical path changer 30 used in the optical wiring mounting structure. 3A is a top view in the XY plane, FIG. 3B is a front view seen from the X direction, and FIG. 3C is a cross-sectional view taken along line AA ′ of FIG. .

  The optical path converter 30 is mounted on the optical device 10 and receives an optical fiber that is an external optical wiring, and converts the optical path between the optical fiber and the diffraction grating 15. The optical path changer 30 includes a main body 31, an optical fiber guide 305 that is formed in the main body 31 and receives an optical fiber, and a lens 35 that is disposed in the space of the optical fiber guide 305.

  An inner wall of the optical fiber guide 305 opposite to the opening 305 a has an inclined surface 34 that is inclined with respect to the optical wiring substrate 12, and a concave surface 32 is formed on the inclined surface 34. A mirror 33 is disposed along at least the concave surface 32 to form a lens 35. When viewed from the main body 31 side, the lens 35 is a concave lens, and when viewed from the space (air layer) of the optical fiber guide 305, the lens 35 is a convex lens.

  The mirror 33 is formed of a highly reflective metal film such as platinum (Pt), gold (Au), or aluminum (Al), or a multilayer dielectric reflection film. The mirror 33 can be formed by a lift-off process using a masking sheet or a dry film made of these materials. Instead of forming the mirror 33 with a reflective film, the lens body 35 may be realized by forming the main body 31 with a metal material such as platinum (Pt), gold (Au), or aluminum (Al).

  The main body 31 on which the inclined surface 34 and the concave surface 32 are formed can be integrally formed by, for example, a mold. Materials include PPS (Polyphenylenesulfide), ABS (Acrylonitrile-Butadiene-Styrene) resin, polyimide, acrylic, epoxy resin materials, and resins filled with fillers such as silica. Can be used. Or you may use what shape | molded glass, such as amorphous silica, a metal, or an alloy.

  The optical path changer 30 is disposed on the optical wiring substrate 12 so that the focal position of the lens 35 coincides with the light emission position of the diffraction grating 15 and the core end of the optical fiber. By using the optical path changer 30, the optical fiber can be mounted from a direction substantially parallel to the main surface of the optical device 10, and a compact and low-profile mounting is realized.

  FIG. 4 is a diagram for explaining a mounting state of the optical fiber 21 to the optical path changer 30. As the external optical wiring, a tape fiber 20 in which a plurality of optical fibers 21 are collected in a ribbon shape with a coating 24 is used. The coating 24 at the tip of the tape fiber 20 is peeled off, and the strand of the optical fiber 21 is inserted into the optical fiber guide 305 of the optical path converter 30. The clad 22 surrounding the core 23 is exposed at the strand of the optical fiber 21.

  The optical fiber guide 305 has a certain clearance 306 between the inner wall of the optical fiber guide 305 and the optical fiber 21 or between the optical fiber 21 and the optical wiring board 12 so that the strand of the optical fiber 21 can be easily inserted. Have. Due to the presence of the clearance and the weight of the tape fiber 20, the optical fiber 21 may wobble within the optical fiber guide 305, and the position of the end face of the core 23 of the optical fiber 21 may deviate from the focal position of the lens 35 (FIG. 4B). reference). In the embodiment, the optical fiber 21 is stably held in the optical fiber guide 305 by combining the optical path converter 30 and the optical fiber attachment member 40 (see FIG. 5) in order to realize a stable optical connection. A combination of the optical path changer 30 and the optical fiber attachment member 40 will be described with reference to FIGS. 5 and 6.

  FIG. 5 is a three-side view of the optical wiring mounting structure 50 of the embodiment. 5A is a top view in the XY plane, FIG. 5B is a front view seen from the X direction, and FIG. 5C is a cross-sectional view taken along line AA ′ of FIG. 5A. . The optical wiring mounting structure 50 includes an optical path changer 30 and an optical fiber attachment member 40. The optical fiber mounting member 40 mounts the optical fiber 21 exposed from the end of the tape fiber 20, and introduces the optical fiber 21 into the optical fiber guide 305 (see FIG. 4) of the optical path converter 30.

  The optical fiber attachment member 40 includes a support plate 45 that supports the optical fiber 21 and a fiber holder 41 that holds the base portion of the strand of the optical fiber 21. Each optical fiber 21 is fixed to the optical fiber attachment member 40 with an adhesive 61. By mounting the optical fiber 21 on the support plate 45, wobbling of the optical fiber 21 due to the weight of the tape fiber 20 is prevented.

  The support plate 45 also has a function of maintaining the optical fiber 21 at a fixed position in the height direction (Z direction) with respect to the lens 35. The optical fiber 21 is pressed against the upper surface of the optical fiber guide 305 by the support plate 45 and holds the optical fiber 21 at an appropriate position with respect to the lens 35 regardless of the weight of the tape fiber 20.

  By inserting the optical fiber mounting member 40 carrying the optical fiber 21 into the optical fiber guide 305 of the optical path changer 30, each optical fiber 21 is held at an appropriate position, and the optical fiber 21 and the optical waveguide 14 are accurately positioned. Realizes stable optical connection.

  FIG. 6 is a view for explaining optical coupling between the optical fiber 21 and the diffraction grating 15 in the optical wiring mounting structure 50. As described above, the diffraction grating 15 functions as an input / output unit of the optical waveguide 14 or an optical interface. The light propagating through the optical waveguide 14 is emitted upward by the diffraction grating 15 at an angle that is perpendicular or nearly perpendicular to the surface of the optical wiring substrate 12. The outgoing light spreads in the space at a predetermined outgoing angle and enters the lens 35. The lens 35 converts the optical path of the outgoing light from the diffraction grating 15 toward the optical fiber 21 and forms an image on the end face of the core 23. Similarly, the light propagating through the optical fiber 21 exits from the end face of the core 23, the optical path is converted to the direction of the diffraction grating 15 by the lens 35, and an image is formed on the diffraction grating 15. The optical path conversion and condensing are performed by the lens 35, and the optical fiber 21 and the optical waveguide 14 are optically coupled with high efficiency.

  For example, when the optical waveguide 14 and the diffraction grating 15 are formed, a positioning mark is formed on the optical wiring board 12 so that the optical path converter 30 can be placed at a predetermined position on the optical wiring board 12 with the accuracy of a general mounter. Can be mounted on. In a state where the optical path changer 30 is mounted on the optical wiring board 12, the lens 35 has a first focal point on the diffraction grating 15 and a second focal point on the end face of the core 23 of the optical fiber 21.

  In addition, after the tape fiber 20 is cut, length variations may occur at the tips of the optical fibers 21. If there is a length variation of about 10 μm at the tip of the optical fiber 21, the end face position of the core 23 is shifted by about 10 μm in the insertion direction of the optical fiber 21. Therefore, it is desirable to optimize the lens 35 and design it to have a focal length of 10 μm or more in the optical axis direction.

  FIG. 7 shows a configuration example of an optical fiber attachment member 40A as an example of the optical fiber attachment member 40 in three views. 7A is a top view in the XY plane, FIG. 7B is a front view seen from the X direction, and FIG. 7C is a side view along the X direction. The optical fiber attachment member 40 </ b> A includes a fiber holder 41 and a support plate 45.

  The fiber holder 41 has grooves 411 corresponding to the number of optical fibers 21 on the joint surface with the support plate 45. The support plate 45 also has guide grooves 451 corresponding to the number of optical fibers 21 on the fiber mounting surface 45a. A fiber guide hole 42 is formed in a part of the groove 411 of the fiber holder 41 and the guide groove 451 of the support plate 45. In this example, the groove 411 and the guide groove 451 are U-shaped grooves having a circular cross section, but are not limited to this example. The fiber guide hole 42 holds the base of the strand of the optical fiber 21 from which the coating 24 has been peeled off.

  The support plate 45 has a bottom surface 45b on the opposite side of the fiber mounting surface 45a. The bottom surface 45b has a slope 45c at the tip in the insertion direction of the optical fiber attachment member 40A. Further, a taper 452 is provided at the corner of the distal end portion on the insertion side. The inclined surface 45c and the taper 452 make it easy to insert the optical fiber attachment member 40A into the optical fiber guide 305 of the optical path converter 30. However, formation of the taper 452 is arbitrary.

  The fiber mounting surface 45a is also bent or curved so that the tip is directed upward with respect to the optical wiring board 12. When the optical fiber mounting member 40 is placed on the horizontal plane H, the fiber mounting surface 45a of the support plate 45 and the inclined surface 45c at the tip of the bottom surface 45b are oriented upward. The support plate 45 having the fiber mounting surface 45a and the inclined surface 45c inclined upward with respect to the horizontal plane functions as a leaf spring. When the optical fiber attachment member 40 </ b> A is inserted into the optical fiber guide 305 of the optical path converter 30, the fiber mounting surface 45 a presses the optical fiber 21 against the upper surface of the optical fiber guide 305.

  The optical fiber attachment member 40A is made of a relatively soft resin such as POM (polyoxymethylene) or ABS, and is manufactured using a technique such as injection molding. By using a soft resin, deformation of the optical fiber 21 is prevented when the optical fiber 21 is pressed against the upper surface of the optical fiber guide 305. It absorbs stress by resin deformation and reduces the effect of clearance variation.

  FIG. 8 shows a state in which the optical fiber 21 is mounted on the optical fiber attachment member 40A. The coating 24 is peeled off from the tip of the four-core tape fiber 20, and the tip of the optical fiber 21 is cut by a fiber cutter, laser processing, or the like. The optical fiber 21 is simultaneously inserted into the fiber guide hole 42 from the fiber holder 41 side of the optical fiber mounting member 40, and is fixed with an adhesive 61 on the insertion side surface of the fiber holder 41. Although illustration is omitted, the opposite end of the tape fiber 20 may also be held by another optical fiber attachment member 40. The length of the tape fiber 20 is adjusted to a desired length.

  The optical fiber 21 receives a force in the Z direction (upward relative to the horizontal plane) at the fiber mounting surface 45 a of the support plate 45. By using the optical fiber attachment member 40 </ b> A, even when the multi-fiber optical fiber 21 is used as the tape fiber 20, each optical fiber 21 is smoothly inserted into the optical path converter 30 while maintaining the pitch of the optical fiber 21. be able to. It is possible to prevent the optical fiber 21 from colliding with the inner wall of the optical fiber guide 305 and being damaged. Further, after insertion, each optical fiber 21 can be pressed and held against the optical fiber guide 305 by the fiber mounting surface 45a.

  FIG. 9 shows a connection sequence of the optical fiber mounting structure 50A using the optical fiber attachment member 40A. In FIG. 9A, the optical fiber attachment member 40 is tilted forward on the optical wiring board 12, and the optical fiber attachment member 40 on which the optical fiber 21 is mounted is inserted into the optical path converter 30. Since the tip of the bottom surface 45b of the support plate 45 of the optical fiber mounting member 40 is a slope 45c, insertion is easy. Further, when a taper 452 (see FIG. 7) is provided at the corner of the support play and the tip of the insertion side of 45, insertion in the width direction is easy.

  By sliding the side 45d on the boundary line between the inclined surface 45c and the bottom surface 45b of the support plate 45 in contact with the optical wiring board 12, the optical fiber attachment member 40 can be smoothly inserted into the optical fiber guide 305.

  In FIG. 9B, while inserting the optical fiber attachment member 40, the optical fiber attachment member 40 is raised from the forward inclined state to a substantially horizontal state. As a result, the optical fiber 21 is pressed against the upper surface of the optical fiber guide 305.

  In FIG. 9C, the optical fiber 21 is inserted to a predetermined position, and the fitting between the optical path changer 30 and the optical fiber attachment member 40 is completed. In this state, the optical fiber 21 is pressed and held on the upper surface of the optical fiber guide 305 by the fiber mounting surface 45 a of the support plate 45. The optical fiber 21 is held at an appropriate position with respect to the lens 35 in the height direction (Z direction) regardless of the presence or variation of the clearance inside the optical fiber guide 305.

  The position of the optical fiber 21 in the arrangement direction (Y direction) is defined by the optical fiber guide 305 and the guide groove 451 on the support plate 45 (see FIG. 7). Further, in order to perform positioning in the insertion direction (X direction) with certainty, the optical path converter 30 may be provided with a fiber position regulating means. The fiber positioning means in the insertion direction will be described later. Alternatively, position restricting means for restricting the intrusion of the optical fiber attachment member 40 in the X direction may be formed on the surface of the optical wiring board 12.

  FIG. 10 shows an optical wiring mounting structure 50B using an optical fiber mounting member 40B as a modification of the optical fiber mounting member 40. The optical fiber attachment member 40B has a support plate 55 having a two-layer structure. The support plate 55 is formed of two layers of a shape memory alloy 551 and a base material 552. The shape memory alloy 551 returns in shape above a certain temperature and functions as a thermal actuator. A titanium-nickel (Ti-Ni) alloy can be used as the shape memory alloy. The base material 552 is the same resin material as the fiber holder 41 of the optical fiber attachment member 40B.

  The support plate 55 has a fiber mounting surface 55a, a bottom surface 55b, and a bottom surface-side inclined surface 55c, as in the configuration of FIG. During the operation of the optical device 10, the fiber mounting surface 55 a has a biasing force that is directed upward from the horizontal plane (the surface of the optical wiring substrate 12), and presses the optical fiber 21 against the upper surface of the optical fiber guide 305.

  For example, the shape recovery temperature is designed to be room temperature or higher by adjusting the Ni content (atm% or wt%). At a temperature lower than room temperature, the shape memory alloy 551 is deformed so that the slope 55c of the shape memory alloy 551 is substantially parallel to the horizontal plane. When the temperature rises in the usage environment, the shape of the shape memory alloy 551 is restored, and the optical fiber 21 is urged upward. At the final insertion position of the optical fiber attachment member 40B, the lens 35 formed in the optical path changer 30 realizes optical path conversion and condensing on the diffraction grating 15 and the core end face of the optical fiber 21.

FIG. 10 shows an optical wiring mounting structure 50C using the optical fiber mounting member 40C. The optical fiber attachment member 40C has a support plate 56 having a two-layer structure. The support plate 56 has a two-layer structure of a piezoelectric ceramic film 561 and a base material 562. The piezoelectric ceramic film 561 functions as a piezoelectric actuator because the film expands and contracts when a voltage is applied. PZT (Pb (Zr, Ti) O ₃ : lead zirconate titanate) is used as the piezoelectric ceramic film 561. The base material 562 is the same resin material as the fiber holder 41 of the optical fiber attachment member 40C.

  The support plate 56 has a fiber mounting surface 56a, a bottom surface 56b, and a bottom surface-side inclined surface 56c, as in the configuration of FIG. During the operation of the optical device 10, the fiber mounting surface 56 a has a biasing force that is directed upward from the horizontal plane (the surface of the optical wiring board 12), and presses the optical fiber 21 against the upper surface of the optical fiber guide 305.

  By applying a voltage to the piezoelectric ceramic film 561 in advance to polarize the piezoelectric ceramic film 561 and setting the direction of the polarization axis to a direction perpendicular to the horizontal plane, an urging force upward from the horizontal plane is applied. At the final insertion position of the optical fiber attachment member 40C, the lens 35 formed in the optical path converter 30 realizes optical path conversion and condensing on the diffraction grating 15 and the core end face of the optical fiber 21.

  FIG. 12 shows an optical path converter 70 as a modification of the optical path converter 30. 12A is a bottom view of the optical path changer 70, FIG. 12B is a perspective view of the optical path changer 70 viewed from the bottom side, and FIG. 12C is a diagram showing the state of the end face of the optical fiber 21. is there. The optical path changer 70 includes a lens abutting surface 706 that regulates the position of the lens 75 and the insertion direction (Y direction) of the optical fiber 21 in the optical fiber guide 705. Similarly to the lens 35, the lens 75 is a concave lens formed in a line on the slope 74 of the optical fiber guide 705.

  The optical fiber guide 705 includes a space 705c that receives the optical fiber on the opening 705a side, a guide groove 73 that extends from the space 705c toward the lens 75, and an end portion of the guide groove 73 that faces the lens 75, and the guide groove 73 and the guide groove. 73 having protrusions 76 disposed between the two. The guide groove 73 is, for example, a V groove. When the optical path changer 70 is used, the guide groove 73 is on the ceiling side, and guides the optical fiber 21 mounted on the support plate 45 (or 55 or 56) of the optical fiber attachment member 40 toward the lens 75.

  The space 705 c has a first taper portion 71 whose width gradually decreases from the opening 705 a toward the guide groove 73. The first taper portion 71 facilitates insertion of the support plate 45 of the optical fiber attachment member 40.

  Each guide groove 73 has a second tapered portion 72 whose width decreases from the boundary with the space 705c toward the lens. The second taper portion 72 facilitates guiding of the strands of each optical fiber 21. The optical fiber 21 is guided toward the lens 35 with the center of the core 23 being along the center of the guide groove 73 in the long axis direction.

  A protrusion 76 protruding in the height direction (Z direction) is provided between the adjacent guide grooves 73 at the end of the guide groove 73 facing the lens 75. The surface of the protrusion 76 opposite to the lens 75, that is, the surface adjacent to the guide groove 73 is a fiber abutting surface 706.

  As shown in FIG. 12C, the fiber abutting surface 706 contacts the end surface of the clad 22 of the optical fiber 21, but does not block the core 23. The light emitted from the end face of the core 23 is reflected by the lens 75 and forms an image on the diffraction grating 15 on the optical wiring board 12. The outgoing light from the diffraction grating 15 is also reflected by the lens 75 and enters the end face of the core 23. Since the tip of each optical fiber 21 is positioned by the fiber abutting surface 706, the optical coupling efficiency is good. When there is a length variation due to collective cutting at the tip of the optical fiber 21, the tip of the longest optical fiber 21 is positioned by the fiber abutting surface 706. By optimizing the lens 75 so that the lens 75 has a focal length of 10 μm or more in the optical axis direction, optical coupling between the core 23 of each optical fiber 21 and the diffraction grating 15 can be realized.

  By providing the fiber abutting surface 706, the end surface of the core 23 is positioned at the focal position of the lens 75.

  The optical path changing structure 70 of FIG. 12 may be combined with any one of the optical fiber mounting members 40 and 40A to 40C to realize the optical wiring mounting structure 50. In this case, the end surface position in the insertion direction (X direction) of the core 23 of the optical fiber 21 is automatically positioned by the fiber abutting surface 706.

  The position in the height direction (Z direction) of the core 23 is defined by the stress in the Z direction of the support plate 45 (or 55 or 56) with respect to the guide groove 73 of the optical fiber guide 705. The position of the core 23 in the arrangement direction (Y direction) is defined by a guide groove 451 formed in the fiber mounting surface 45a of the support plate 45.

  By inserting the optical fiber attachment member 40 (including 40A to 40C) on which the optical fiber 21 is mounted into the optical path converter 70, the position of the end face of the optical fiber 21 with respect to the diffraction grating 15 on the optical wiring board 12 is uniquely determined. .

  FIG. 13 is a schematic diagram of an optical module 90 using the optical wiring mounting structure 50 (including 50A and 50B) of the embodiment. The optical module 90 includes, for example, the optical device 10 mounted on the module substrate 91, a light source chip 93, and an electric circuit chip 92. The optical device 10 includes an optical waveguide 14 formed by silicon photonics technology, an optical interface (such as the diffraction grating 15 in FIG. 2), and an optical circuit 16. An optical wiring mounting structure 50 (including 50A and 50B) is disposed in the optical device 10, and optical communication is performed with an external optical device. The light source chip 93 has a laser element. A driver circuit and a TIA (transimpedance amplifier) are formed in the electric circuit chip 92.

  The optical device 10, the electric circuit chip 92, and the light source chip 93 are mounted on the module substrate 91 by, for example, a BGA (Ball Grid Array). The optical circuit 16 of the optical device 10 is connected to the electric circuit chip 92 by, for example, TSV (Through Silicon Via) and BGA (not shown). Or you may electrically connect by wire bonding etc. As a result, an electric drive signal is supplied from the driver to the optical modulator in the optical circuit 16, and a current signal is supplied from the photodetector in the optical circuit 16 to the TIA.

  The optical device 10 and the light source chip 93 are connected using an optical fiber or a flexible waveguide (not shown), and continuous light output from the light source chip 93 is input to the optical modulator of the optical device 10.

  The optical module 90 uses the optical wiring mounting structure 50 to realize a compact and stable optical connection with an optical device on an external module. Since the optical wiring mounting structure 50 connects the external optical wiring (for example, the multi-fiber tape fiber 20) to the optical device 10 in a direction parallel to the module substrate 91, low-profile mounting is realized. Further, by inserting the optical fiber attachment member 40 into the optical path changer 30, the relative position with respect to the diffraction grating 15 is automatically determined, and mounting is easy.

  As shown in FIG. 13A, the optical wiring mounting structure 50 may be bonded and fixed to the optical device 10 with an adhesive 63. Only the rear end side in the insertion direction of the optical fiber attachment member 40 may be adhered, or the adhesive 63 can be injected into the optical path changer 30 to be firmly adhered and fixed. In the latter case, it is desirable to use a transparent resin as the adhesive 63 at the wavelength of the light used. A transparent adhesive 63 is filled in the gap between the diffraction grating 15 and the optical fiber 21 inside the optical path changer 30. As the adhesive 63, for example, a transparent resin such as epoxy can be used.

  FIG. 13B shows an example in which a hook 81 is formed on the optical fiber attachment member 40. The latch-shaped hook 81 can be formed together with the optical fiber attachment member 40 by injection molding. The hook 82 of the hook 81 is hooked on the corner of the optical device 10 so that the optical fiber mounting member 40 is fitted to the optical path converter 30 and the optical wiring mounting structure 50 is fixed to the optical device 10. By using the hook 81, when fixing the optical fiber attachment member 40 with the adhesive 63, it is not necessary to hold the optical fiber attachment member 40 so that it does not fall out of the optical path changer 30 due to its own weight. This simplifies the assembly process. In the configuration of FIG. 13B, the adhesive 63 does not necessarily have to be used, so that the optical fiber attachment member 40 that holds the tape fiber 20 can be made detachable.

  FIG. 14 is a schematic diagram of the system board 1 in which the optical module 90 having the optical wiring mounting structure 50 is used. 14A is a top view of the system board 1, and FIG. 14B is a cross-sectional view taken along the line BB ′ of FIG. 14A.

  The system board 1 is an example of an electronic device, and is used for a large-sized computing device such as a supercomputer or a server. In this example, the optical module 90 is used on the system board 1 as an optical transceiver for connecting between packages on which LSI chips 5 are mounted.

  The LSI chip 5 is mounted on the package substrate 3 as an example of an electronic component, and a plurality of optical modules 90 are arranged in the vicinity of the LSI chip 5. A plurality of such package substrates 3 are mounted on the board substrate 2, and each package substrate 3 is connected to the board substrate 2 by a BGA 4. A high-speed electrical signal output from the LSI chip 5 of a certain package substrate 3 is output as an optical signal modulated at high speed by the optical module 90 on the same package substrate 3. The optical signal is connected to an optical module around the LSI mounted on another package substrate by a tape fiber 20 serving as an external optical wiring. The optical signal is converted again into an electrical signal by the counterpart optical transceiver and exchanged with other LSI chips.

  As shown in FIG. 14B, a heat sink 9 may be mounted on the upper surfaces of the LSI chip 5 and the optical module 90 to cool the system board 1 during operation. The cooling device is not limited to the heat sink 9, and a cooling plate for water cooling or the like may be used.

  In each optical module 90 mounted on the system board 1, each optical fiber 21 of the tape fiber 20 is easily and accurately positioned with respect to the optical interface (for example, the diffraction grating 15) on the optical device 10. The optical coupling efficiency in each optical module 90 is high, and the quality of optical transmission can be improved. Further, since the tape fiber 20 as the external optical wiring is mounted in the horizontal direction, the outer shape of the optical module 90 is simplified and the handling becomes easy. When mounted on the system board 1, the tape fiber 20 is configured to extend from each optical module 90 in a direction horizontal to the board substrate 2, and the system board 1 can be easily handled.

  As mentioned above, although this invention has been described based on embodiment, it is not limited to embodiment mentioned above. The optical wiring mounting structure of the embodiment can be applied not only to single mode but also to multimode propagation.

  The support plate 45 of the optical fiber attachment member 40 is not limited to the configuration shown in FIGS. 7, 10, and 11. Any configuration that holds the optical fiber by pressing it against the upper surface of the optical fiber guide 305 of the optical path converter 30 or the optical fiber guide 705 of the optical path converter 70, such as a bimetal or cantilever leaf spring, can be employed. Further, the protrusion 76 having the fiber abutting surface 706 of FIG. 12 may be applied to the optical path converter 30 of FIG.

  Even in these application examples, a compact and stable optical connection is realized. The optical waveguide 14 on the optical device 10 and the optical fiber 21 that is an external optical wiring can be optically connected easily and with high accuracy in terms of component fabrication accuracy and mounting accuracy.

The following notes are presented for the above explanation.
(Appendix 1)
An optical path changer disposed in an optical device having a light input / output unit for entering and exiting light upward with respect to the substrate surface;
An optical fiber mounting member for holding an optical fiber and holding the optical fiber in the optical path converter;
Have
The optical path changer has an optical fiber guide for guiding the optical fiber, and a lens formed on an inner wall of the optical fiber guide,
At least a part of the support plate is inserted into the optical fiber guide, and the optical fiber is held at a position where an end surface of the optical fiber coincides with a focal point of the lens.
(Appendix 2)
2. The optical wiring mounting structure according to appendix 1, wherein a distal end portion in the insertion direction of the support plate faces upward from the surface when the support plate is placed on the surface of the optical device.
(Appendix 3)
The support plate has a fiber mounting surface for mounting the optical fiber, and a bottom surface opposite to the fiber mounting surface,
The optical wiring mounting structure according to appendix 1 or 2, wherein the bottom surface and the fiber mounting surface are inclined upward with respect to the surface of the optical device on the distal end side in the insertion direction.
(Appendix 4)
The optical fiber mounting structure according to appendix 3, wherein the fiber mounting surface has a guide groove for holding the optical fiber (appendix 5).
5. The optical wiring mounting structure according to any one of appendices 1 to 4, wherein the support plate is a plate-like plate.
(Appendix 6)
The optical wiring mounting structure according to any one of appendices 1 to 4, wherein the support plate has a two-layer structure of a base material and a shape memory alloy.
(Appendix 7)
5. The optical wiring mounting structure according to any one of appendices 1 to 4, wherein the support plate has a two-layer structure of a base material and a piezoelectric ceramic film.
(Appendix 8)
The optical wiring mounting structure according to any one of appendices 1 to 7, wherein the support plate has a taper at a corner portion on a distal end side in the insertion direction.
(Appendix 9)
9. The optical wiring mounting structure according to any one of appendices 1 to 8, wherein the optical fiber attachment member has a hook that fits with the optical device.
(Appendix 10)
10. The optical wiring mounting structure according to any one of appendices 1 to 9, wherein the optical fiber mounting member is fixed to the optical path converter with an adhesive.
(Appendix 11)
11. The optical wiring mounting structure according to any one of appendices 1 to 10, wherein the adhesive is transparent, and the adhesive is filled in a space between the light input / output unit and the optical fiber.
(Appendix 12)
The optical path changer has an inclined surface on an inner wall opposite to the opening of the optical fiber guide, and the lens is formed on the inclined surface. Optical wiring mounting structure.
(Appendix 13)
The optical path mounting structure according to any one of appendices 1 to 12, wherein the optical path changer has a fiber abutting surface for restricting insertion of the optical fiber at a position facing the lens.
(Appendix 14)
14. The optical wiring mounting structure according to any one of appendices 1 to 13, wherein the optical path changer has a guide groove for receiving the optical fiber on an upper surface inside the optical fiber guide.
(Appendix 15)
The optical path converter is
Two or more guide grooves formed on the upper surface inside the optical fiber guide;
A fiber abutting surface that is disposed between the adjacent guide groove and the guide groove at the end of the guide groove in the insertion direction of the optical fiber and restricts the insertion of the optical fiber;
The optical wiring mounting structure according to any one of appendices 1 to 12, characterized by comprising:
(Appendix 16)
A module board;
An optical device mounted on the module substrate;
An optical wiring mounting structure that is mounted on the optical device and connects an optical waveguide on the optical device and an external optical wiring;
Have
The optical wiring mounting structure is
An optical path changer disposed on the optical device;
A mounting member for holding the external optical wiring in the optical path converter with a support plate for mounting the external optical wiring;
Have
The optical path converter has a guide space for guiding the external optical wiring, and a lens formed on an inner wall of the guide space,
At least a part of the support plate is inserted into the guide space, and the external optical wiring is held at a position where the end surface of the external optical wiring coincides with the focal point of the lens.
(Appendix 17)
The optical module according to appendix 16,
Electronic components,
An electronic device having a package substrate on which is mounted.
(Appendix 18)
An optical path converter is disposed at a predetermined position on an optical device having an optical input / output unit that inputs and emits light upward with respect to the substrate surface,
An optical fiber is mounted on a support plate, and the optical fiber is inserted into the optical path converter while sliding the support plate on the surface of the optical device.
In the optical path converter, the optical fiber is held at a position where an end face of the optical fiber coincides with a focal point of a lens formed inside the optical path converter.
An optical wiring mounting method characterized by the above.
(Appendix 19)
Insert the support plate into the guide space of the optical path converter by tilting it forward to the tip side,
After inserting a certain amount of the optical fiber, raise the support plate, press and hold the optical fiber against the upper surface of the guide space at the tip of the support plate,
Item 18. The optical wiring mounting method according to appendix 18, wherein

1 System board (electronic equipment)
5 LSI chip (electronic component)
DESCRIPTION OF SYMBOLS 10 Optical device 12 Optical wiring board 14 Optical waveguide 15 Diffraction grating (Optical input / output part or optical interface)
20 Tape fiber 21 Optical fiber (external optical wiring)
23 Core 30, 70 Optical path changer 34, 74 Inclined surface 35, 75 Lens 40 Optical fiber mounting member 41 Fiber holder 45 Support plate 50 Optical wiring mounting structure 76 Projection 90 Optical module 305 Optical fiber guide 451 Guide groove 452 Taper (support plate) )
706 Fiber abutting surface

Claims (8)

An optical path changer disposed in an optical device having a light input / output unit for entering and exiting light upward with respect to the substrate surface;
An optical fiber mounting member for holding an optical fiber and holding the optical fiber in the optical path converter;
Have
The optical path changer has an optical fiber guide for guiding the optical fiber, and a lens formed on an inner wall of the optical fiber guide,
At least a part of the support plate is inserted into the optical fiber guide, and the optical fiber is held at a position where an end surface of the optical fiber coincides with a focal point of the lens.   2. The optical wiring mounting structure according to claim 1, wherein a distal end portion of the support plate in an insertion direction faces upward from the surface when the support plate is placed on the surface of the optical device.   The optical wiring mounting structure according to claim 1, wherein the support plate is a plate-like plate.   The optical wiring mounting structure according to claim 1, wherein the support plate has a two-layer structure of a base material and a shape memory alloy.   The optical wiring mounting structure according to claim 1, wherein the support plate has a two-layer structure of a base material and a piezoelectric ceramic film.   6. The optical wiring mounting structure according to claim 1, wherein the optical path changer has a fiber abutting surface for restricting insertion of the optical fiber at a position facing the lens. 7. . A module board;
An optical device mounted on the module substrate;
An optical wiring mounting structure that is mounted on the optical device and connects an optical waveguide on the optical device and an external optical wiring;
Have
The optical wiring mounting structure is
An optical path changer disposed on the optical device;
A mounting member for holding the external optical wiring in the optical path converter with a support plate for mounting the external optical wiring;
Have
The optical path converter has a guide space for guiding the external optical wiring, and a lens formed on an inner wall of the guide space,
At least a part of the support plate is inserted into the guide space, and the external optical wiring is held at a position where the end surface of the external optical wiring coincides with the focal point of the lens. An optical path converter is disposed at a predetermined position on an optical device having an optical input / output unit that inputs and emits light upward with respect to the substrate surface,
An optical fiber is mounted on a support plate, and the optical fiber is inserted into the optical path converter while sliding the support plate on the surface of the optical device.
In the optical path converter, the optical fiber is held at a position where an end face of the optical fiber coincides with a focal point of a lens formed inside the optical path converter.
An optical wiring mounting method characterized by the above.

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