JP2013092685A - Flexible photoelectric wiring module - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enable electromagnetic noise emission to be suppressed.SOLUTION: A flexible photoelectric wiring module comprises: a flexible photoelectric wiring plate 10 with an optical wiring path 12, first electrical wiring 11i, second electrical wiring 11a and third electrical wiring 11c, 11e; an optical semiconductor element 13a mounted on the flexible photoelectric wiring plate, electrically connected to the first electrical wiring and optically coupled to the optical wiring path; a drive IC 14a mounted on the flexible photoelectric wiring plate, electrically connected to the first electrical wiring, the second electrical wiring and the third electrical wiring for driving the optical semiconductor element via the first electrical wiring, inputting/outputting an electric signal via the second electrical wiring and receiving supply of a power source potential and a ground potential via the third electrical wiring; and a capacitor 16a electrically connected to the third electrical wiring. The module has a circuit region 15a where the optical semiconductor element, the drive IC and the capacitor are mounted.

Description

  Embodiments described herein relate generally to a flexible photoelectric wiring module on which a capacitor is mounted.

  A flexible wiring board having flexibility is used as wiring disposed on a mechanically movable part or a curved surface part of an electronic device. In addition, by improving the performance of electronic devices such as bipolar transistors and field effect transistors, the operating speed of large-scale integrated circuits (LSIs) has been dramatically improved. It has become a problem. In order to cope with such a problem, a flexible photoelectric wiring module for wiring a high-speed signal with light has been proposed.

JP 2009-80451 A

  A flexible photoelectric wiring module capable of suppressing electromagnetic noise radiation is provided.

  A flexible photoelectric wiring module according to an embodiment is mounted on a flexible flexible photoelectric wiring board having an optical wiring path, a first electric wiring, a second electric wiring, and a third electric wiring, and the flexible photoelectric wiring board. An optical semiconductor element electrically connected to the first electrical wiring and optically coupled to the optical wiring path; and mounted on the flexible photoelectric wiring board; and the first electrical wiring and the second electrical wiring Electrically connected to the wiring and the third electrical wiring, drive the optical semiconductor element via the first electrical wiring, input and output electrical signals via the second electrical wiring, A driving IC to which a power supply potential and a ground potential are supplied via a third electric wiring; and a capacitor electrically connected to the third electric wiring; and the optical semiconductor element and the driving IC, The capacitor and Having mounted circuit region.

The schematic block diagram of the flexible photoelectric wiring module concerning 1st Embodiment. The schematic block diagram of the flexible photoelectric wiring module concerning 2nd Embodiment. The schematic block diagram of the flexible photoelectric wiring module concerning 3rd Embodiment. The schematic block diagram of the flexible photoelectric wiring module concerning 3rd Embodiment. The schematic block diagram of the flexible photoelectric wiring module concerning 4th Embodiment. The schematic block diagram of the flexible photoelectric wiring module concerning 5th Embodiment.

  The flexible photoelectric wiring module according to the embodiment can be used as a wiring module for transmitting a video signal output from an information processor to a display in an electronic device such as a mobile phone or a notebook PC.

  In the flexible photoelectric wiring module according to the embodiment, an optical semiconductor element and a driving IC for driving the optical semiconductor element are mounted on a flexible photoelectric wiring board having an optical wiring path and an electrical wiring. The flexible photoelectric wiring module converts an electrical signal input from one end (for example, the application processor side) into an optical signal and transmits the optical signal, and converts the optical signal into an electrical signal at the other end (for example, the display side) and outputs it. Optical signals do not emit electromagnetic noise. For this reason, a flexible photoelectric wiring module that optically transmits a signal can reduce electromagnetic noise emission compared to a flexible wiring module that electrically transmits a signal.

  While optical signal transmission is possible in this way, the flexible photoelectric wiring module still requires electrical wiring (power wiring) for supplying power from one end to the other. Therefore, when electromagnetic noise is radiated from the optical semiconductor element, the driving IC, the electric wiring for inputting / outputting signals, and the electric wiring for supplying power to the driving IC and coupled to the above power wiring, this power wiring becomes a noise source. Electromagnetic noise is radiated from the entire flexible photoelectric wiring module.

  Therefore, in the flexible photoelectric wiring module according to the embodiment, by mounting a capacitor, electromagnetic noise radiation from the electric wiring that supplies power to the driving IC and electromagnetic noise coupling to the electric wiring such as the power supply wiring are suppressed. ing. Thereby, electromagnetic noise radiation from the flexible photoelectric wiring module can be suppressed, and the merit of optical wiring that does not radiate electromagnetic noise can be enjoyed to the maximum.

  Hereinafter, the present embodiment will be described with reference to the drawings. Here, some specific materials and configurations will be described as examples, but any material or configuration having a similar function can be implemented. Therefore, it is not limited to the following embodiment.

[1] First Embodiment A schematic configuration of a flexible photoelectric wiring module according to the first embodiment will be described with reference to FIG. 1A is a top view of the flexible photoelectric wiring module, FIG. 1B is a cross-sectional view in the wiring length direction along the line IB-IB in FIG. 1A (near the circuit region), and FIG. c) is an enlarged view of the vicinity of the chip capacitor.

[1-1] Flexible Photoelectric Wiring Module As shown in FIG. 1A, the flexible photoelectric wiring module of this embodiment is a flexible having an electric wiring 11 (11 a to 11 j) and an optical wiring path (optical waveguide core) 12. An optical semiconductor element 13 (light emitting element 13a, light receiving element 13b), driving IC 14 (14a, 14b), and chip capacitor 16 (16a, 16b) are mounted on the photoelectric wiring board 10. The electrical wiring 11 includes a signal input wiring 11a, a signal output wiring 11b, a power supply wiring 11c and a ground wiring 11e of the driving IC 14a, a power supply wiring 11d and a ground wiring 11f of the driving IC 14b, a wiring 11i connecting the light emitting element 13a and the driving IC 14a, and light reception. A wiring 11j connecting the element 13b and the driving IC 14b, and other electrical wirings 11g and 11h are provided. The circuit region 15 (15a, 15b) on which the optical semiconductor element 13, the driving IC 14, and the chip capacitor 16 are mounted is located in the end region of the flexible photoelectric wiring board 10.

  In the flexible photoelectric wiring module of the present embodiment, the driving IC 14a drives the light emitting element 13a in accordance with the electric signal input from the electric wiring 11a, and the driving IC 14b amplifies the light receiving current generated by the light receiving element 13b, thereby causing the electric wiring 11b. High-speed signal transmission (for example, 3 Gbps) is possible by outputting an electrical signal. In addition, using the other electrical wirings 11g and 11h, power supply from one end of the flexible photoelectric wiring module to the other end, and low-speed signal transmission such as I2C (Inter-Integrated Circuit) or SPI (Serial Peripheral Interface) (for example, 10 kbps) is possible.

[1-2] Chip Capacitor As shown in FIG. 1A, in the flexible photoelectric wiring module of this embodiment, a chip capacitor 16a (for example, a capacitance of 100 pF) is provided between the power supply wiring 11c and the ground wiring 11e of the drive IC 14a. A chip capacitor 16b (for example, a capacitance of 100 pF) is provided between the power supply wiring 11d and the ground wiring 11f of the driving IC 14b. The chip capacitors 16a and 16b function as bypass capacitors, preventing potential fluctuations in the power supply wirings 11c and 11d and the ground wirings 11e and 11f when the driving ICs 14a and 14b operate, thereby preventing the electric wirings 11c, 11d, 11e, and 11f. It is possible to suppress the electromagnetic noise radiation from. Thereby, it is possible to suppress electromagnetic noise coupling to the other electrical wirings 11g and 11h that connect one end and the other end of the flexible photoelectric wiring module, and to greatly suppress electromagnetic noise radiation from the flexible photoelectric wiring module. .

  The chip capacitor 16 can also be mounted on an external printed wiring board connected to the flexible photoelectric wiring module. In this case, the parasitic impedance of the electric wiring between the chip capacitor 16 and the driving IC 14, the flexible photoelectric circuit, and the like. The function as a bypass capacitor is significantly reduced by the parasitic impedance of a connecting member (for example, wire bonding, FPC (Flexible Printed Circuit) connector, ACF (Anisotropic Conductive Film)) that electrically connects the wiring module and the printed wiring board. Therefore, by mounting the chip capacitor 16 on the flexible photoelectric wiring board 10, it is possible to receive the maximum effect of suppressing electromagnetic noise radiation.

  The chip capacitor 16 is mounted on the side opposite to the driving IC 14 with respect to the optical semiconductor element 13. Here, the optical semiconductor element 13, the driving IC 14, and the chip capacitor 16 are arranged so as to be aligned in the longitudinal direction (X direction) of the flexible photoelectric wiring board 10. That is, the width in the Y direction (width in the direction perpendicular to the wiring length direction of the flexible photoelectric wiring module) of the circuit region 15 in which the optical semiconductor element 13, the driving IC 14, and the chip capacitor 16 are mounted is minimized. Thereby, for example, when a flexible photoelectric wiring module is disposed in a through hole of a movable part such as a hinge often used in an electronic device such as a mobile phone or a notebook PC, the flexible photoelectric wiring board 10 is bent along the wiring length direction. Alternatively, by rounding, the width of the flexible photoelectric wiring module in the Y direction can be made the same as the width of the circuit region 15 at a minimum. For this reason, it becomes possible to arrange | position a flexible photoelectric wiring module to a smaller through-hole, and it can promote size reduction of an electronic device.

  It is also possible to mount a chip capacitor 16 between the optical semiconductor element 13 and the driving IC 14. However, in this case, the electrical wirings 11i and 11j that connect the optical semiconductor element 13 and the driving IC 14 become longer, the electrical signal that drives the optical semiconductor element 13 deteriorates, and the signal transmission quality deteriorates. There is a possibility that noise emission from 11j increases. It is also possible to mount a chip capacitor 16 on the signal input wiring 11a and the signal output wiring 11b. However, in this case, the characteristic impedance of the signal input wiring 11a and the signal output wiring 11b may change and the signal transmission quality may deteriorate.

  As shown in FIG. 1C, the chip capacitor 16a has electrical connection terminals 19 at both ends thereof. The electrical connection terminal 19 is mounted on the flexible photoelectric wiring board 10 so as not to overlap the optical wiring path 12 when viewed from above in a direction perpendicular to the surface of the flexible photoelectric wiring board 10. In this figure, in the area below the chip capacitor 16a, the electric wiring 11c and the electric wiring 11e are separated, and the optical wiring path 12 crosses below the gap between the electric wiring 11c and the electric wiring 11e. The electrical connection terminal 19 of the chip capacitor 16a is connected to the ends of the electrical wirings 11c and 11e, and the electrical connection terminal 19 and the optical wiring path 12 do not overlap. As a result, when the electrical connection terminal 19 of the chip capacitor 16a is solder-connected to the electrical wirings 11c and 11e, it is possible to prevent the optical wiring path 12 from being deformed or altered by heating and increasing optical loss. The chip capacitor 16b in the circuit region 15b has the same configuration as the chip capacitor 16a. The optical wiring path 12 does not have to overlap with the electrical connection terminal 19 of the chip capacitor 16a. For example, the optical wiring path 12 may cross above or below the chip capacitor 16 in FIG. Further, when there is no fear of deformation or alteration of the optical wiring path 12 due to heating, the optical wiring path 12 and the electrical connection terminal 19 may overlap.

  The chip capacitor 16 is, for example, a multilayer ceramic capacitor, and includes an optical semiconductor element 13 (for example, 0.3 mm in length, 0603 (length: 0.6 mm, width: 0.3 mm), 0402 (length: 0.4 mm, width: 0.2 mm), or the like. It is desirable to have a small size as compared with 0.3 mm (width) or drive IC 14 (for example, height 0.7 mm, width 1 mm). For example, the width of the chip capacitor 16 in the Y direction is smaller than the width of the drive IC 14 in the Y direction, and it is desirable that both ends of the chip capacitor 16 in the Y direction are located inside the both ends of the drive IC 14 in the Y direction. .

  Note that a tantalum capacitor, an aluminum electrolytic capacitor, or a film capacitor may be used as the chip capacitor 16. The chip capacitor 16 may be two terminals or three terminals. One chip capacitor 16 is not limited to be mounted in one circuit region 15, and a plurality of chip capacitors 16 may be provided in one circuit region 15. The chip capacitors 16a and 16b have the same arrangement with respect to the optical semiconductor element 13 and the driving IC 14 in FIG. 1A, but may be arranged differently. Between the two circuit regions 15a and 15b, the number of chip capacitors 16 is not limited to be the same, and may be different. The capacities, areas, etc. of the chip capacitors 16a, 16b may be the same or different.

[1-3] Flexible photoelectric wiring board As shown in FIG. 1B, the flexible photoelectric wiring board 10 includes a base film 20 (for example, polyimide, thickness 25 μm), an electric wiring 11 (11a to 11j) (for example, rolled Cu). , Thickness 12 μm), optical wiring path (optical waveguide core) 12 (for example, thickness 30 μm), optical waveguide cladding 21 (21a, 21b) (for example, total thickness 50 μm), coverlay 22 (for example, polyimide, thickness 25 μm) Are laminated and bonded together. Moreover, the flexible photoelectric wiring board 10 has flexibility, for example, is 10 mm in width and 150 mm in length.

[1-4] Electric Wiring As shown in FIG. 1B, the Cu foil used as the electric wiring 11 is integrated with the base film 20 through an adhesive layer, or the surface of the Cu foil is roughened to form a base film. What was directly heat-pressed to 20 may be used. The electrical wiring 11 may be formed by patterning a Cu foil laminated on the base film 20, and a part thereof may be plated with, for example, Ni / Au (for example, 5 μm / 0.3 μm in thickness) and used as an electrical connection terminal. . A part of the electrical wiring 11 is connected to the optical semiconductor element 13 and the driving IC 14 and can transmit an optical signal by electrical input / output. Note that the patterning shape of the electrical wiring 11 can be changed as needed. Further, it is desirable that the surface of the electrical wiring 11 is insulated by laminating a cover lay or a photoresist, except for electrical connection terminals, heat dissipation lands and the like.

[1-5] Optical Wiring As shown in FIG. 1B, the optical waveguide core 12 and the optical waveguide cladding 21 are transparent materials (for example, acrylic resin and epoxy resin) with respect to the optical transmission wavelength. These constitute an optical wiring layer. In order to form this optical wiring layer, a first optical waveguide clad 21a (for example, thickness 10 μm) and an optical waveguide core 12 are laminated and bonded in order on the base film 20, and the above-described patterning pattern of the electric wiring 11 is formed. In addition, the optical waveguide core 12 is patterned. Subsequently, the second optical waveguide clad 21b (for example, 40 μm thick) is laminated on the patterned optical waveguide core 12 and bonded together. Since the optical waveguide core 12 has a higher refractive index than the optical waveguide cladding 21, the light incident on the optical waveguide core 12, which is an optical wiring path, is confined in the optical waveguide core 12 and propagates.

  By forming the optical wiring layer as described above, the alignment of the optical waveguide core 12 and the electric wiring 11 can be performed with very high accuracy. Thereby, in the flexible photoelectric wiring board 10, for example, compared with the composite type flexible photoelectric wiring board in which the optical flexible wiring board formed individually and the electric flexible wiring board are aligned and bonded together, the optical semiconductor element 13 and The alignment accuracy with the optical waveguide core 12 can be increased. Furthermore, the relative position fluctuation between the optical semiconductor element 13 and the optical waveguide core 12 due to temperature change can be reduced, and a flexible photoelectric wiring module with high productivity and reliability can be realized.

  The optical waveguide core 12 described above can also be formed by pattern exposure on an optical waveguide film using a resin whose refractive index changes when exposed to light as the optical waveguide film. In the optical wiring layer forming method described above, an example is shown in which the electrical wiring 11 is first formed and the optical waveguide core 12 is formed by patterning in alignment with the patterning shape of the electrical wiring 11. It is also possible to pattern the electrical wiring 11 by forming a wiring layer and aligning it with the patterning shape of the optical waveguide core 12. Note that the number of optical waveguide cores 12 and the patterning shape can be appropriately changed as necessary.

  At both ends of the optical waveguide core 12, 45 degree mirrors are provided. As a result, light propagating through the optical waveguide core 12 is taken out in a direction substantially perpendicular to the surface of the flexible photoelectric wiring board 10, and light incident from the direction substantially perpendicular to the surface of the flexible photoelectric wiring board 10 is taken as the optical waveguide. It can be coupled to the core 12. The 45-degree mirror can be formed by, for example, laser ablation, dicing, pressing, or the like, and metal (for example, Au) may be vapor-deposited on the mirror surface in order to improve reflectivity. The angle of the 45-degree mirror (the angle with respect to the light traveling direction) does not have to be exactly 45 degrees, but is preferably within the range of 30 to 60 degrees.

[1-6] Optical Semiconductor Element The optical semiconductor element 13 uses a light emitting element 13a or a light receiving element 13b fabricated on a GaAs substrate, for example, and has a light emission or light reception wavelength of, for example, 850 nm. As the light emitting element 13a, for example, a surface emitting laser (Vertical Cavity Surface Emitting LASER: VCSEL) can be used. For example, a PIN photodiode (PD) can be used as the light receiving element 13b.

  The optical semiconductor element 13 is mounted by using, for example, an ultrasonic flip chip mounting method so that the light emitting portion or the light receiving portion faces the 45 degree mirror formed on the optical waveguide core 12. Thereby, the light emitting element 13a mounted on one end side of the optical waveguide core 12 and the light receiving element 13b mounted on the other end side are optically coupled through the optical waveguide core 12, and one end side and the other of the flexible photoelectric wiring module are connected. Optical signal transmission can be performed between the end sides. Further, the optical semiconductor element 13 is electrically connected to the electrical wiring 11 (11i, 11j) via the Au bumps 17 formed on the optical semiconductor element 13, thereby transmitting an optical signal by electrical input / output. Is possible. As an electrical connection method, for example, bump connection by solder bumps or wire bonding connection may be used.

  The optical semiconductor element 13 may be formed on a compound semiconductor (for example, GaAlAs / GaAs, InGaAs / InP, SiGe, etc.) or a substrate of Si, Ge, etc. It can be changed. Further, as the optical semiconductor element 13, an array chip in which a plurality of optical elements are formed in one chip may be used, or an optical semiconductor element in which both a light emitting element and a light receiving element are formed in one chip. It may be used. Furthermore, as the optical semiconductor element 13, an optical semiconductor element capable of emitting and receiving light with one element may be used.

  In FIG. 1A, one light emitting element 13a is mounted on one end side of the flexible photoelectric wiring board 10 and one light receiving element 13b is mounted on the other end side. However, another optical semiconductor element is mounted. May be. In FIG. 1 (a), the transmission direction of the optical signal is a single direction from one end side to the other end side of the flexible photoelectric wiring board 10, but a light receiving element is mounted on one end side and a light emitting element is mounted on the other end side. The optical signal transmission in the opposite direction to that shown in FIG. 1A may be performed, or a light emitting element and a light receiving element are mounted on one end side, and a light receiving element and a light emitting element are mounted on the other end side to perform bidirectional optical signal transmission. May be.

  Further, as the light emitting element 13a which is the optical semiconductor element 13, various light emitting elements such as a light emitting diode and a semiconductor laser can be used. As the light receiving element 13b which is the optical semiconductor element 13, various light receiving elements such as a PIN photodiode, an MSM photodiode, an avalanche photodiode, and a photoconductor can be used.

[1-7] Drive IC
The driving IC 14 is mounted on the flexible photoelectric wiring board 10 by using, for example, an ultrasonic flip chip mounting method, and is electrically connected to the electric wiring 11 (11a, 11b) through the Au bump 17 formed on the driving IC 14. Yes. The drive IC 14a supplies a bias current and a drive current to the light emitting element 13a in accordance with an electric signal input from the electric wiring 11a. The driving IC 14b applies a reverse bias voltage to the light receiving element 13b, amplifies the light receiving current generated by the light receiving element 13b, and outputs an electric signal to the electric wiring 11b. The drive IC 14 may be a drive IC having both functions of the drive ICs 14a and 14b. Further, for example, another circuit function such as a serialization function for converting a parallel electric signal into a serial electric signal and a deserialization function for converting a serial electric signal into a parallel electric signal may be provided. If the drive IC 14a for the light emitting element 13a is equipped with a serialization function and the drive IC 14b for the light receiving element 13b is equipped with a deserialization function, a plurality of electrical input signals are converted into a small number of optical signals and transmitted. can do.

[1-8] Others An underfill resin 18 is applied to the bottom and side surfaces of the optical semiconductor element 13 and the driving IC 14. The underfill resin 18 is, for example, an epoxy resin, and is solidified by, for example, heating or ultraviolet irradiation. With the underfill resin 18, the electrical connection between the electrical wiring 11, the optical semiconductor element 13, and the driving IC 14 can be held with high reliability. In addition, the gap formed between the optical semiconductor element 13 and the optical waveguide core 12 is filled to improve the optical coupling efficiency, and the reflection of light in the gap formed between the optical semiconductor element 13 and the optical waveguide core 12 is suppressed. It is possible to perform optical coupling with high efficiency and high reliability.

  The underfill resin used for filling the gap formed between the optical semiconductor element 13 and the optical waveguide core 12 and the underfill resin used for maintaining the electrical connection between the electrical wiring 11, the optical semiconductor element 13 and the driving IC 14 are as follows. Different resins may be used. In any case, it is desirable that the underfill resin used for filling the gap formed between the optical semiconductor element 13 and the optical waveguide core 12 is transparent to the optical transmission wavelength.

  A coverlay 22 is laminated on the second optical waveguide clad 21b via an adhesive layer made of, for example, an epoxy resin. As a result, the optical wiring layer can be protected.

  For example, a reinforcing plate made of polyimide having a thickness of 100 μm may be further laminated on the back surfaces of both ends of the flexible photoelectric wiring module including the circuit region 15. Thereby, the flexibility of the chip mounting portion is reduced, the mounting of the optical semiconductor element 13, the driving IC 14, and the chip capacitor 16 is facilitated, and the optical semiconductor element 13, the driving IC 14, and the chip are bent by bending the flexible photoelectric wiring board. It is possible to prevent the capacitor 16 from being damaged.

[1-9] Effect As described above, according to the first embodiment, the optical semiconductor elements 13 a and 13 b and the optical semiconductor elements 13 a and 13 b are added to the flexible photoelectric wiring board 10 having the optical wiring path 12 and the electric wiring 11. Drive ICs 14a and 14b are mounted, the chip capacitor 16a is electrically connected to the power supply wiring 11c and the ground wiring 11e of the drive IC 14a, and the chip capacitor 16b is electrically connected to the power supply wiring 11d and the ground wiring 11f of the drive IC 14b. Connecting. Since the chip capacitors 16a and 16b function as bypass capacitors when the driving ICs 14a and 14b operate, the potential fluctuations of the power supply wirings 11c and 11d and the ground wirings 11e and 11f are prevented, and the electric wirings 11c and 11d. , 11e, 11f to suppress electromagnetic noise radiation. Thereby, the electromagnetic noise coupling | bonding to the other electric wiring 11g, 11h which connects the other end of a flexible photoelectric wiring module can be suppressed, and the electromagnetic noise radiation from a flexible photoelectric wiring module can be suppressed.

  Further, according to the first embodiment, the chip capacitor 16 is mounted on the side opposite to the driving IC 14 with respect to the optical semiconductor element 13 so that the chip capacitor 16, the optical semiconductor element 13 and the driving IC 14 are arranged in the X direction. Be placed. For this reason, it is possible to minimize the width in the Y direction of the circuit region 15 in which the optical semiconductor element 13, the driving IC 14, and the chip capacitor 16 are mounted, and promote downsizing of the electronic device.

[2] Second Embodiment The second embodiment is an example in which the length in the X direction of the circuit region 15 is minimized as compared with the first embodiment.

  Below, the schematic structure of the flexible photoelectric wiring module concerning 2nd Embodiment is demonstrated using FIG. In FIG. 2, the same components as those in FIG. 1 are denoted by the same reference numerals, and detailed description of the same components is omitted.

[2-1] Chip Capacitor As shown in FIG. 2, the chip capacitor 16 (16 a 1, 16 a 2, 16 b 1, 16 b 2) in the second embodiment is the Y-direction (flexible photoelectric wiring board 10) of the optical semiconductor element 13 or the drive IC 14. The circuit area 15 is mounted so as to be within the length of the circuit area 15 in the X direction. Specifically, the chip capacitors 16a1 and 16a2 are arranged on both sides in the Y direction of the drive IC 14a in the circuit region 15a, and the chip capacitors 16b1 and 16b2 are respectively arranged on both sides in the Y direction of the drive IC 14b in the circuit region 15b. Be placed.

  In this embodiment, the chip capacitor 16a1 is electrically connected to the power supply wiring 11c and the electric wiring 11k of the driving IC 14a, and the chip capacitor 16a2 is electrically connected to the ground wiring 11e and the electric wiring 11m of the driving IC 14a. The capacitor 16b1 is electrically connected to the power supply wiring 11d and the electric wiring 11l of the driving IC 14b, and the chip capacitor 16b2 is electrically connected to the ground wiring 11f and the electric wiring 11n of the driving IC 14b. Here, it is desirable to apply a ground potential to the electric wirings 11k and 11l from the outside, for example, and supply a power supply potential to the electric wirings 11m and 11n from the outside, for example. Thereby, like the first embodiment, it is possible to suppress electromagnetic noise radiation of the flexible photoelectric wiring module.

  The chip capacitor 16 may be disposed on both sides of the optical semiconductor element 13 in the Y direction. However, in order to minimize the influence of the parasitic impedance of the electric wiring connecting the drive IC 14 and the chip capacitor 16, the chip capacitor 16 is provided. It is desirable to be located in the vicinity. In this case, the width of the chip capacitor 16 in the X direction is smaller than the width of the drive IC 14 in the X direction, and the both ends of the chip capacitor 16 in the X direction may be located inside the both ends of the drive IC 14 in the X direction. desirable.

  Two chip capacitors 16 are not limited to being mounted in one circuit region 15, and one or more chip capacitors 16 may be provided in one circuit region 15. Between the two circuit regions 15a and 15b, the number of chip capacitors 16 is not limited to be the same, and may be different.

[2-2] Effects As described above, in the second embodiment, similarly to the first embodiment described above, the chip capacitor 16a1 is electrically connected to the power supply wiring 11c and the ground wiring 11k, and the ground wiring 11e The chip capacitor 16a2 is electrically connected to the power supply wiring 11m, the chip capacitor 16b1 is electrically connected to the power supply wiring 11d and the ground wiring 11l, and the chip capacitor 16b2 is electrically connected to the ground wiring 11f and the power supply wiring 11n. For this reason, it is possible to provide a flexible photoelectric wiring module capable of suppressing electromagnetic noise radiation.

  Further, according to the second embodiment, the chip capacitor 16 is arranged in the region of the side surface in the Y direction of the optical semiconductor element 13 or the driving IC 14 so as to be within the length of the circuit region 15 in the X direction. For this reason, the length of the circuit region 15 in the X direction can be minimized. Thereby, for example, when a flexible photoelectric wiring module is mounted on a circuit board in an electronic device such as a mobile phone or a notebook PC, the flexible photoelectric wiring module is arranged by folding the flexible photoelectric wiring module closer to the end. The required space can be reduced, and the electronic device can be reduced in size.

[3] Third Embodiment The third embodiment is an example in which the flexible electric wiring board is used and the cost of the flexible photoelectric wiring module is reduced as compared with the first and second embodiments.

  Below, the schematic structure of the flexible photoelectric wiring module concerning 3rd Embodiment is demonstrated using FIG. 3A and FIG. 3B. 3A (a) and 3B (a) are top views of the flexible photoelectric wiring module, and FIG. 3A (b) is a cross-sectional view in the wiring length direction along the line IIIAB-IIIAB in FIG. 3A (circuit area). FIG. 3B (b) is a cross-sectional view (around the circuit region) in the wiring length direction along the line IIIBB-IIIBB in FIG. 3B (a). 3A and 3B, the same parts as those in FIGS. 1 and 2 are denoted by the same reference numerals, and detailed description of the same configuration is omitted.

[3-1] Flexible Photoelectric Wiring Module As shown in FIGS. 3A and 3B, in the flexible photoelectric wiring module of the third embodiment, the flexible photoelectric wiring board 10 (for example, 1 mm in width and 10 mm in length) attaches the adhesive sheet 40. Are mounted on a flexible electrical wiring board 30 (for example, a width of 10 mm and a length of 150 mm), and the electrical wiring 11 (11a to 11f, 11k to 11n) of the flexible photoelectric wiring board 10 and the electrical wiring 31 (31a of the flexible electrical wiring board 30). To 31f and 31k to 31n) are electrically connected by wire bonding 41, respectively.

  In the flexible photoelectric wiring module of this embodiment, high-speed signal transmission is performed by the optical wiring of the flexible photoelectric wiring board 10, and power supply and low-speed signal transmission are performed by the electric wiring 31 of the flexible electric wiring board 30. The area of 10 is minimized. Thereby, cost reduction is possible compared with the case where all the electrical wiring and optical signal transmission are performed only by the flexible photoelectric wiring board 10. FIG.

  In the flexible photoelectric wiring module of this embodiment, the back surface of the flexible photoelectric wiring board 10 is mounted on the surface of the flexible electric wiring board 30, but the surface of the flexible photoelectric wiring board 10 is mounted on the surface of the flexible electric wiring board 30. Alternatively, the front surface of the flexible photoelectric wiring board 10 may be mounted on the back surface of the flexible electrical wiring board 30, or the back surface of the flexible photoelectric wiring board 10 may be mounted on the back surface of the flexible electrical wiring board 30.

  Further, in the flexible photoelectric wiring module of this embodiment, the wire bonding 41 is used for the electrical connection between the electric wiring 11 of the flexible photoelectric wiring board 10 and the electric wiring 31 of the flexible electric wiring board 30. Alternatively, the electrical wiring 11 and the electrical wiring 31 may be connected using an anisotropic conductive film (ACF) or an anisotropic conductive paste (ACP).

[3-2] Chip Capacitor In the third embodiment, the chip capacitor 16 is mounted on the flexible photoelectric wiring board 10 as in the first and second embodiments.

  In the example shown in FIG. 3A (a), the chip capacitor 16 (16a, 16b) is mounted on the opposite side of the drive IC 14 with respect to the optical semiconductor element 13 as in the first embodiment, and the optical semiconductor element 13 and the drive are driven. The IC 14 and the chip capacitor 16 are arranged so as to be aligned in the longitudinal direction (X direction) of the flexible photoelectric wiring board 10. The chip capacitor 16a is disposed between the power supply wiring 11c and the ground wiring 11e of the drive IC 14a, and the chip capacitor 16b is disposed between the power supply wiring 11d and the ground wiring 11f of the drive IC 14b. Here, the power supply wirings 11c and 11d of the flexible photoelectric wiring board 10 are electrically connected to the electric wirings 31c and 31d of the flexible electric wiring board 30, respectively, and the ground wirings 11e and 11f of the flexible photoelectric wiring board 10 are flexible electric circuits. The wirings 30 are electrically connected to the electrical wirings 31e and 31f, respectively. Therefore, for example, a ground potential is applied to the electrical wirings 31e and 31f from the outside, and a power supply potential is applied to the electrical wirings 31c and 31d from the outside, for example. Function as.

  In the example shown in FIG. 3B (a), the chip capacitor 16 (16a1, 16a2, 16b1, 16b2) is formed in the circuit region in the region of the side surface in the Y direction of the optical semiconductor element 13 or the driving IC 14 as in the second embodiment. Each is mounted so as to be within the length of 15 in the X direction. The chip capacitor 16a1 is disposed between the power supply wiring 11c and the ground wiring 11k of the drive IC 14a, the chip capacitor 16a2 is disposed between the power supply wiring 11m of the drive IC 14a and the ground wiring 11e, and the chip capacitor 16b1 is driven. The chip capacitor 16b2 is arranged between the power supply wiring 11n of the driving IC 14b and the ground wiring 11f. The chip capacitor 16b2 is arranged between the power supply wiring 11d of the IC 14b and the ground wiring 11l. Here, the power supply wirings 11c, 11d, 11m, and 11n of the flexible photoelectric wiring board 10 are electrically connected to the electric wirings 31c, 31d, 31m, and 31n of the flexible electric wiring board 30, respectively, and the ground of the flexible photoelectric wiring board 10 is obtained. The wirings 11e, 11f, 11k, and 11l are electrically connected to the electrical wirings 31e, 31f, 31k, and 31l of the flexible electrical wiring board 30, respectively. Therefore, it is possible to supply power to the drive IC 14 by applying a ground potential from the outside to the electrical wirings 31e, 31f, 31k, 31l and applying a power supply potential from the outside to the electrical wirings 31c, 31d, 31m, 31n, for example. At the same time, the chip capacitor 16 functions as a bypass capacitor.

[3-3] Flexible Electric Wiring Board As shown in FIGS. 3A (b) and 3B (b), the flexible electric wiring board 30 has flexibility, and electric wiring 31 (for example, rolled Cu foil, 12 μm thick), a base film 32 (for example, polyimide, thickness 25 μm), a reinforcing plate 33 (for example, polyimide, thickness 100 μm), and the like. The flexible electrical wiring board 30 has a laminated structure in which an electrical wiring 31, a base film 32, and a reinforcing plate 33 are laminated and bonded, and has a width of 10 mm and a length of 150 mm, for example.

  The Cu foil used as the electrical wiring 31 may be one that is integrated with the base film 32 via an adhesive layer, or one that is surface-roughened and directly thermocompression bonded to the base film 32. The electrical wiring 31 may be formed by patterning a Cu foil laminated on the base film 32, and a part thereof may be plated with, for example, Ni / Au (for example, 5 μm / 0.3 μm in thickness) and used as an electrical connection terminal. . Note that the patterning shape of the electrical wiring 31 can be changed as needed. Further, it is desirable that the surface of the electrical wiring 31 is insulated by laminating a cover lay or a photoresist, except for the electrical connection terminals and the radiating land.

  The adhesive sheet 40 adheres and fixes the flexible photoelectric wiring board 10 and the flexible electric wiring board 30. As the adhesive sheet 40, for example, a pressure-sensitive adhesive made of an epoxy resin, an acrylic resin, a polyester resin, or the like, or a substrate made of a resin film such as polyimide or a metal foil such as Al or Cu is used. What formed the adhesive layer which consists of said adhesive on both surfaces etc. can be used. The thickness of the adhesive sheet 40 is 50 μm, for example. In FIGS. 3A (a) and 3B (b), the adhesive sheet 40 is provided in the vicinity of the mounting portion of the optical semiconductor element 13 and the driving IC 14 located at both ends of the flexible photoelectric wiring board 10, but the flexible photoelectric wiring board. One adhesive sheet from one end to the other may be provided. Further, instead of using the adhesive sheet 40, the flexible photoelectric wiring board 10 may be fixed to the flexible electric wiring board 30 with a mold resin, for example.

[3-4] Effect As described above, in the third embodiment, the chip capacitor 16 is mounted between the power supply wiring and the ground wiring of the drive IC 14 as in the first and second embodiments described above. For this reason, it is possible to suppress electromagnetic noise radiation of the flexible photoelectric wiring module.

  In the third embodiment, as in the first and second embodiments described above, the length in the X direction of the circuit region in which the optical semiconductor element 13, the drive IC 14, and the chip capacitor 16 are mounted (in the case of FIG. 3B). ) Or the width in the Y direction (in the case of FIG. 3A) can be minimized, and downsizing of the electronic device can be promoted.

  Further, in the third embodiment, high-speed signal transmission is performed by the optical wiring of the flexible photoelectric wiring board 10, and power supply and low-speed signal transmission are performed by the electric wiring 31 of the flexible electric wiring board 30. Thereby, since the area of the flexible photoelectric wiring board 10 can be suppressed to a necessary minimum, the cost can be reduced as compared with the case where all the electrical wiring and optical signal transmission are performed only by the flexible photoelectric wiring board 10.

[4] Fourth Embodiment In the fourth embodiment, the chip capacitor 16 is mounted on the flexible electrical wiring board 30, thereby avoiding damage to the optical wiring path due to the heating process as compared with the third embodiment. It is possible.

  Below, the schematic structure of the flexible photoelectric wiring module concerning 4th Embodiment is demonstrated using FIG. In FIG. 4, the same components as those in FIGS. 3A and 3B are denoted by the same reference numerals, and detailed description of the same components is omitted.

[4-1] Chip Capacitor As shown in FIG. 4, the flexible photoelectric wiring module of the fourth embodiment is different from the third embodiment in that the chip capacitor 16 is mounted on the flexible electric wiring board 30.

  The electric wiring 11 (11a to 11f) of the flexible photoelectric wiring board 10 and the electric wiring 31 (31a to 31f) of the flexible electric wiring board 30 are electrically connected, for example, by wire bonding. Accordingly, the power supply wiring 11c and the chip capacitor 16a1 of the driving IC 14a, the ground wiring 11e and the chip capacitor 16a2 of the driving IC 14a, the power supply wiring 11d and the chip capacitor 16b1 of the driving IC 14b, and the ground wiring 11f and the chip capacitor 16b2 of the driving IC 14b are electrically connected. It is connected. For this reason, it is desirable to apply, for example, a ground potential to the electrical wirings 31e, 31f, 31k, 31l from the outside, and to apply a power supply potential to the electrical wirings 31c, 31d, 31m, 31n from the outside, for example. As a result, power can be supplied to the drive IC 14, the chip capacitor 16a1 is disposed between the power supply wiring 31c and the ground wiring 31k, and the chip capacitor 16a2 is disposed between the power supply wiring 31m and the ground wiring 31e. The chip capacitor 16b1 is disposed between the power supply wiring 31d and the ground wiring 31l, the chip capacitor 16b2 is disposed between the power supply wiring 31n and the ground wiring 31f, and the chip capacitor 16 functions as a bypass capacitor. .

  In the present embodiment, the chip capacitor 16 is mounted on the flexible electrical wiring board 30, but it is desirable that the chip capacitor 16 be disposed near the drive IC 14 (for example, within 5 mm).

[4-2] Effects As described above, in the fourth embodiment, the chip capacitor 16 is mounted between the power supply wiring and the ground wiring, as in the first to third embodiments described above. For this reason, it is possible to suppress electromagnetic noise radiation of the flexible photoelectric wiring module.

  In the fourth embodiment, the chip capacitor 16 is mounted on the flexible electrical wiring board 30. For this reason, before mounting the flexible photoelectric wiring board 10 on the flexible electrical wiring board 30, it is possible to solder-connect the chip capacitor 16 to the flexible electrical wiring board 30 by a solder reflow process. Thereby, it is possible to prevent damage to the optical wiring path 12 such that the optical wiring path 12 is deformed or deteriorated due to heating in the solder reflow process and optical loss increases.

  In the fourth embodiment, since the chip capacitor 16 is mounted on the flexible electrical wiring board 30, the area of the flexible photoelectric wiring board 10 can be minimized and the cost can be reduced.

[5] Fifth Embodiment The fifth embodiment is an example in which the flexibility or twistability of the wiring region of the flexible photoelectric wiring module is improved.

  The schematic configuration of the flexible photoelectric wiring module according to the fifth embodiment will be described with reference to FIG. In FIG. 5, only the outer shapes of the flexible photoelectric wiring board 10 and the flexible electric wiring board 30 are shown, and the other parts are omitted. However, the specific configuration applies the configuration of the other embodiment described above. It is possible.

  As shown in FIG. 5A, in the flexible photoelectric wiring module of the fifth embodiment, a through slit 50 (for example, width 0.1 mm) parallel to the wiring direction of the flexible electric wiring board 30 is provided, and the flexible electric wiring board is provided. The 30 wiring regions are divided into a plurality of fine lines (for example, 1 mm in width), and the flexible photoelectric wiring board 10 is mounted on one divided thin line.

  As shown in FIG. 5B, in the flexible photoelectric wiring module shown in FIG. 5A, one end region, the wiring region, and the other end region of the flexible photoelectric wiring module have a crank shape. A plurality of fine lines are overlapped so that the front and back surfaces of adjacent fine lines are opposed to each other, and the plurality of fine lines are bundled using a bundle band 51. Thereby, a wiring area | region can be handled as a thin flexible wiring board of 1 bundle. For this reason, in addition to the bending operation, it is possible to cope with a rotation operation, a twisting operation, and the like.

  Note that it is desirable that the widths and intervals of all the thin lines are substantially equal. Thereby, when a flexible photoelectric wiring module is bundled as mentioned above, it can suppress that a tension | tensile_strength concentrates on one part thin wire. In addition, since all of the plurality of fine lines are pulled equally, the alignment of the plurality of fine lines is good in a region where the plurality of fine lines are bundled, and some of the fine lines are not scattered. In addition, you may use the other method (For example, a several thin wire | line is overlap | superposed so that the surface and surface of an adjacent fine wire, or a back surface and a back surface may oppose) how to overlap the thin line of a flexible photoelectric wiring module.

  For example, a fluororesin-based seal tape can be used for the bundle band 51. It is desirable to use a tape without an adhesive for the bundle band 51 so that each thin line can move inside the bundle band 51. Thereby, the slack and stress of a thin wire | line can be removed. Note that the number of the bundled wire bands 51 can be appropriately changed as necessary, and a bundled wire band that is continuous from one end to the other end of the bundled thin wires may be used instead of individual bundled wire bands. In addition, when there is no fear that a plurality of bundled thin lines may be separated or when it may be separated, the bundle band 51 may not be used. It is desirable that no electrical wiring be provided in the portion where the through slit 50 is formed.

  The entire surface of the flexible photoelectric wiring board 10 may be affixed to the flexible electric wiring board 30, or only the region near the end may be affixed to the flexible electric wiring board 30. Moreover, you may remove the thin wire | line of the flexible electrical wiring board 30 of the location which arrange | positions the flexible photoelectric wiring board 10. FIG. In this case, the flexible photoelectric wiring board 10 and the flexible electrical wiring board 30 are not overlapped in the wiring region, and the minimum bending radius when bending or sliding the wiring region of the flexible photoelectric wiring module can be reduced. Furthermore, the flexible photoelectric wiring board 10 and the flexible electric wiring board 30 are not rubbed, and durability against repeated bending and sliding can be improved.

  Each embodiment mentioned above can be variously changed. For example, FPC, FFC, or the like can be applied to the flexible electrical wiring board 30. In addition to polyimide, a liquid crystal polymer or another resin can be used for the base film of the flexible electrical wiring board 30 and the flexible photoelectric wiring board 10. The electrical wiring 31 of the flexible electrical wiring board 30 may be a single layer or multiple layers. The electrical wiring 11 and the optical wiring layer of the flexible photoelectric wiring board 10 may be a single layer or multiple layers.

  Although several embodiments of the present invention have been described, these embodiments are presented by way of example and are not intended to limit the scope of the invention. These novel embodiments can be implemented in various other forms, and various omissions, replacements, and changes can be made without departing from the scope of the invention. These embodiments and modifications thereof are included in the scope and gist of the invention, and are included in the invention described in the claims and the equivalents thereof.

  DESCRIPTION OF SYMBOLS 10 ... Flexible photoelectric wiring board, 11 ... Electric wiring, 12 ... Optical wiring path, 13 ... Optical semiconductor element, 14 ... Drive IC, 15 ... Circuit area | region, 16 ... Chip capacitor, 17 ... Bump, 18 ... Underfill resin, 19 DESCRIPTION OF SYMBOLS Electrical connection terminal, 20 ... Base film, 21 ... Cladding, 22 ... Cover film, 30 ... Flexible electrical wiring board, 31 ... Electrical wiring, 32 ... Base film, 33 ... Reinforcement plate, 40 ... Adhesive sheet, 41 ... Bonding wire ... 50 through-slit, 51.

Claims (5)

A flexible flexible photoelectric wiring board having an optical wiring path, a first electrical wiring, a second electrical wiring, and a third electrical wiring;
An optical semiconductor element mounted on the flexible photoelectric wiring board, electrically connected to the first electrical wiring, and optically coupled to the optical wiring path;
Mounted on the flexible photoelectric wiring board, electrically connected to the first electric wiring, the second electric wiring, and the third electric wiring, and the optical semiconductor element via the first electric wiring A drive IC that inputs / outputs electrical signals via the second electrical wiring and is supplied with a power supply potential and a ground potential via the third electrical wiring;
A capacitor electrically connected to the third electrical wiring;
Comprising
A flexible photoelectric wiring module having a circuit region in which the optical semiconductor element, the driving IC, and the capacitor are mounted. A flexible flexible electrical wiring board having a fourth electrical wiring and a fifth electrical wiring;
The capacitor is mounted on the flexible photoelectric wiring board,
The fourth electrical wiring is electrically connected to the second electrical wiring;
The flexible photoelectric wiring module according to claim 1, wherein the fifth electric wiring is electrically connected to the third electric wiring. The capacitor is mounted on the flexible photoelectric wiring board,
The optical semiconductor element, the driving IC and the capacitor are arranged in the longitudinal direction of the flexible photoelectric wiring board,
The capacitor is disposed on the opposite side of the driving IC with respect to the optical semiconductor element in the circuit region,
3. The flexible photoelectric wiring module according to claim 1, wherein an electrical connection terminal of the capacitor does not overlap the optical wiring path when viewed from above in a direction perpendicular to the surface of the flexible photoelectric wiring board. The capacitor is mounted on the flexible photoelectric wiring board,
The optical semiconductor element and the driving IC are arranged in the longitudinal direction of the flexible photoelectric wiring board,
3. The flexible photoelectric device according to claim 1, wherein the capacitor is disposed in a region in a direction perpendicular to the longitudinal direction of the flexible photoelectric wiring board with respect to the optical semiconductor element or the driving IC in the circuit region. Wiring module. A flexible flexible electrical wiring board having a fourth electrical wiring and a fifth electrical wiring;
The capacitor is mounted on the flexible electrical wiring board,
The fourth electrical wiring is electrically connected to the second electrical wiring;
The flexible photoelectric wiring module according to claim 1, wherein the fifth electric wiring is electrically connected to the third electric wiring.

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