JPH11248960A - Connecting method for optical circuit and manufacture of optical circuit board using the method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide the connecting method for an optical circuit which can connect the optical circuit precisely without requiring any large space and the method for manufacturing an optical circuit board by using the method. SOLUTION: A rigid substrate and a flexible base material are put one over the other to cross the optical fiber fixed to the rigid substrate and the optical fiber provided extending to outside the flexible base material, and both the optical fibers 1 are fixed by adding a resin-based adhesive to the crossing point by a dispenser 4 while pressing the crossing point by a press-contacting tool 2 which has a groove 21 and vibrates an ultraviolet wave and then sending a hot blast 5 by a fan after moving the dispenser 4 so that its tip will not be clogged with the hot blast. Photosensitive resin which becomes flexible after setting is applied over this fiber laid surface and made to set with ultraviolet rays after vacuum defoaming. This photosensitive resin layer formation is repeated twice to form a protection and fixation layer for the fiber, thereby manufacturing the optical circuit board having a fiber extension part of the flexible base material.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a method for connecting an optical circuit and a method for manufacturing an optical circuit board using the method.

[0002]

2. Description of the Related Art An optical fiber is used for communication using light having a very high frequency as a carrier wave, and has been developed as a communication medium capable of performing high-quality transmission over a long distance with little loss. In recent years, it has been proposed and developed to use an optical fiber developed for use in long-distance communication for short-distance communication or transmission in a device instead of an electric wire having a small amount of information. I have.

For example, Japanese Patent Application Laid-Open No. 61-186908 discloses an optically active element, an optically passive element, and a drive circuit for an optically active element in a communication system or a measurement system which performs mutual conversion between light and electrons. Provide three or more layers of substrates,
An arrangement in which an optical circuit is provided between the substrates is disclosed.
Here, as for the optical fiber, it is described that an optical branching / coupling device having a length of 60 mm is provided at a distance of 2 mm between two optical fibers on a UV resin substrate.

Japanese Patent Application Laid-Open No. 1-180505 discloses an optical circuit forming method in which an optical fiber is laid on a substrate via an adhesive layer. Here, it is described that the optical fiber was laid on an ABS resin substrate on which an acrylic adhesive layer was formed using a tool for laying.

Further, Japanese Patent Application Laid-Open No. 4-31905 discloses that a flexible substrate having an optical fiber sandwiched between a rigid substrate and the flexible substrate is floated from the middle of the rigid substrate to form an optical fiber. There is disclosed a circuit board whose tip can be connected to a connector.

Further, as disclosed in Japanese Patent Application Laid-Open No. 1-183605, there is known an optical circuit board having a condensing lens which receives light from an optical fiber at an angle on an end face of the board.

[0007]

SUMMARY OF THE INVENTION Incidentally, Japanese Patent Application Laid-open No. Sho 61
As disclosed in JP-A-186908, in a communication system or a measurement system that performs mutual conversion between light and electrons, a substrate provided with an optically active element, an optically passive element, and a drive circuit for the optically active element has three layers. Providing the above, arranging the optical circuit between the substrates increases the thickness of the substrate, and if there is a failure in the optical circuit, all the substrate parts including the electronic circuit must be replaced, which is not economical There was a problem that. In addition, in such a method, there is a large gap between the alignment accuracy required for optical interconnection and the accuracy with which optical elements are electrically mounted. There is also a problem that a margin for absorption is required, and the size of the substrate becomes large, which is not practical.

In that sense, Japanese Patent Laid-Open Publication No. 1-18050
As disclosed in Japanese Unexamined Patent Application Publication No. 5 (1993) -195, and Japanese Unexamined Patent Application Publication No. 4-31905, it is more economical to make only the optical circuit independent.

However, as disclosed in JP-A-1-180505, when a tool is laid on the adhesive layer, all parts of the optical fiber are fixed to the adhesive, and signals are taken out from the optical circuit. To peel off that part,
Alternatively, there is a problem that the portion must not be fixed, and the unfixed optical fiber is easily damaged.

Further, as disclosed in Japanese Patent Application Laid-Open No. 4-31905, a flexible substrate having an optical fiber interposed therebetween is attached to a rigid substrate, and the flexible substrate is lifted from the middle of the rigid substrate. Even if the tip of the optical fiber can be connected to the connector, the unfixed optical fiber is still susceptible to breakage, and the optical connector connected to the tip of the floating optical fiber has a large component area. In addition to the problem that the optical interconnection part becomes large, there is also a problem that the length of the unfixed fiber increases because the optical connection part needs to be moved during the operation of connecting the connector.

Further, as disclosed in Japanese Patent Application Laid-Open No. 1-183605, when a condensing lens for receiving light from an optical fiber while being inclined is provided on the end face of the substrate, when the inclination angle is reduced, the fixing position of the optical fiber is reduced. Has to be reduced, and when it is increased, the height of the substrate is increased.

The present invention relates to a method for connecting an optical circuit that can connect optical circuits accurately without taking up space, and a method for efficiently manufacturing an optical circuit board using the method.

[0013]

According to the method of connecting optical circuits of the present invention, two plastic optical fibers are crossed,
The method is characterized in that pressure is applied while applying energy by vibration to the intersection.

It is preferable that the pressure applied at this time be reduced from the time when the plastic optical fiber starts to deform, since the optical fiber will not be crushed.

In this method, it is preferable that the crossing point is the end of each plastic optical fiber.

In this method, the energy due to the vibration can be the energy due to the ultrasonic vibration or the energy due to the laser beam, and the energy due to the ultrasonic wave is converted into heat by applying the ultrasonic vibration to the optical fiber. Softening certain plastic materials
It will melt.

Using this method, an optical fiber is mounted and fixed on the surface of a flexible substrate in the form of a circuit, and the optical fiber is provided so as to extend outside the flexible substrate, and is fixed to another rigid substrate. An optical circuit board can be manufactured by intersecting an optical fiber provided outside the flexible base material and connecting the intersection by applying pressure while applying energy by vibration to the intersection.

Further, a flexible substrate is placed on a rigid substrate to which the optical fiber is fixed, and while the optical fiber is placed in a circuit on the surface of the flexible substrate, the optical fiber is extended to the outside of the flexible substrate. While fixing to the rigid substrate, the optical fiber originally fixed and the optical fiber extended beyond the flexible base material are crossed and connected by applying pressure while applying energy by vibration to the intersection. Thus, the optical circuit board can be manufactured.

Further, an optical fiber is mounted and fixed on the surface of the flexible base material in a circuit form, and the optical fiber fixed to another rigid substrate and the optical fiber provided on the flexible base material are connected so that the optical fibers are in direct contact with each other. The optical circuit board can also be manufactured by stacking, crossing the optical fibers of each other, and connecting the intersection by applying pressure while applying energy by vibration.

Further, an optical fiber is placed and fixed in a circuit shape on the surface of a flexible base material having a hole formed in advance at a place to be connected, and the flexible base material and a rigid board are stacked, and the optical fiber fixed to the rigid board is provided. An optical circuit board can also be manufactured by crossing an optical fiber provided on a flexible substrate and applying pressure while applying energy by vibration to the intersection.

Further, the optical fiber is mounted and fixed on the surface of the flexible base material in a circuit form, and the optical fiber is provided so as to extend outside the flexible base material.
An optical circuit can also be formed by intersecting an optical fiber fixed to another flexible substrate with an optical fiber extending outside the flexible substrate and applying pressure while applying energy by vibration to the intersection. A substrate can be manufactured.

Further, a flexible substrate is placed on a flexible substrate on which an optical fiber is fixed, and the optical fiber is placed on the surface of the flexible substrate in a circuit shape.
While extending the optical fiber to the outside of the flexible substrate and fixing it to the flexible substrate, the optical fiber originally fixed and the optical fiber extended outside the flexible substrate are crossed, and at the intersection, An optical circuit board can also be manufactured by connecting by applying pressure while applying energy by vibration.

Further, an optical fiber is mounted and fixed on the surface of the flexible base material in a circuit form, and the optical fiber fixed to another flexible substrate and the optical fiber provided on the flexible base material are arranged so that the optical fibers are in direct contact with each other. The optical circuit board can also be manufactured by stacking and crossing the optical fibers of each other and applying pressure while applying energy by vibration to the intersection.

Further, an optical fiber is placed and fixed in a circuit shape on the surface of a flexible base material having a hole at a place to be connected in advance, and the flexible base material and another flexible substrate are overlapped. ,
An optical circuit board can also be manufactured by crossing an optical fiber provided on the flexible base material and applying pressure while applying energy by vibration to the intersection.

[0025]

DESCRIPTION OF THE PREFERRED EMBODIMENTS In the present invention, there are ultrasonic vibration and laser light as a method of intersecting two plastic optical fibers and applying energy due to vibration to the intersection thereof. A method using a bonding apparatus used for wire bonding, particularly wedge bonding, can be used. In addition, when manufacturing a multi-wire wiring board, it is also used for fixing an insulated wire on an insulating base material surface coated with an adhesive. An ultrasonic vibrating needle used for a head portion of a wiring machine can be used.

As a second method of applying this energy, there is a laser, and an infrared laser and an excimer laser can be used. However, in order to reduce the thermal effect, a laser beam having a short pulse and a high energy density per time is used. Is suitable.

In order to apply the pressure while applying the energy, it is possible to simply perform the operation while holding down with a finger.
In order to fix the conditions or control the manufacturing time, it is necessary to make a special jig such as a spatula having a groove for fixing an optical fiber.

[0028]

Example 1 A polyimide film having a thickness of 70 μm was used as a base material, and an acrylic rubber-based adhesive film was adhered to one surface of the base material. The diameter was 125 μm using a pressing jig by ultrasonic vibration and an XY table driven by NC. The optical fiber made of plastic was laid in a circuit shape, and the optical fiber was extended to the outside of the outer shape of the substrate to obtain a flexible substrate. MC, a 0.8mm thick glass cloth / epoxy double-sided copper-clad laminate
After etching unnecessary portions of the surface copper foil of LE-679 (trade name, manufactured by Hitachi Chemical Co., Ltd.) to form a circuit, an IC chip, a chip resistor, a chip capacitor,
A chip transistor, etc. are mounted, and an acrylic rubber-based adhesive film with holes drilled on the mounted electronic parts is attached,
The optical fiber was placed and fixed there. Next, the signal extraction region of the optical fiber was cut from the surface to the bottom of the optical fiber by a dicing saw, and the optical fiber 4
Five cuts were obtained. Thereafter, an infrared laser was irradiated from the back surface of the substrate until a hole having a diameter of 0.3 mm reached the optical fiber. A laser light receiving element was attached to the side of the hole where the optical fiber was not fixed, and connected to a circuit on the surface. The rigid substrate thus fabricated and the flexible substrate are overlapped, and the optical fiber fixed to the rigid substrate and the optical fiber extending outward from the flexible substrate intersect with each other, as shown in FIG. To
After pressing the intersection by the pressure welding device 2 having the groove 21 and ultrasonically vibrating, a fluorinated polyimide resin adhesive is added to the intersection with the dispenser 4 so that the tip of the dispenser 4 moves so as not to be caught by hot air. A hot air 5 was sent by a fan to fix both optical fibers 1. After curing, the fiber laying surface was coated with a flexible amide epoxy photosensitive resin having a thickness of 100 μm, vacuum degassed, and then cured by ultraviolet rays. This formation of the photosensitive resin layer was repeated twice to form a protective fixing layer for the fiber, and an optical circuit board having a fiber extension portion made of a flexible substrate was manufactured.

Example 2 A polyimide film having a thickness of 70 μm was used as a base material, and an acrylic rubber-based adhesive film was adhered to one side of the base material. A plastic optical fiber was laid in a circuit shape, and the optical fiber was extended to the outside of the outer shape of the base material to obtain a flexible base material. After etching unnecessary parts of the surface copper foil of a double-sided copper-clad flexible film using a polyimide film with a thickness of 70 μm as a base material to form a circuit, the IC chip, chip resistor, chip capacitor, chip transistor, etc. are mounted, An acrylic rubber-based adhesive film with holes was applied to the mounted electronic components, and an optical fiber was placed and fixed there. Next, the signal extraction region of the optical fiber was cut from the surface to the bottom of the optical fiber by a dicing saw, and a 45-degree cut surface of the optical fiber was obtained. Thereafter, an infrared laser was irradiated from the back surface of the substrate until a hole having a diameter of 0.3 mm reached the optical fiber. A laser light receiving element was attached to the side of the hole where the optical fiber was not fixed, and connected to a circuit on the surface to form a flexible substrate. A flexible substrate is superimposed on the flexible substrate thus produced,
The optical fiber fixed to the flexible substrate and the optical fiber extended outward from the flexible base material are crossed, and as shown in FIG. While holding down the place,
A fluorinated polyimide resin adhesive was added to the intersection with a dispenser 4 and the tip of the dispenser 4 was moved so as not to be clogged with hot air, and then hot air 5 was sent by a fan to fix both optical fibers 1. An amide epoxy photosensitive resin having flexibility after curing is placed on the fiber laying surface.
After coating with a thickness of 00 μm and defoaming in a vacuum, it was cured by ultraviolet rays. This formation of the photosensitive resin layer was repeated twice to form a protective fixing layer for the fiber, and an optical circuit board having a fiber extension portion made of a flexible substrate was manufactured.

Example 3 A 70 μm-thick polyimide film was used as a substrate, and an acrylic rubber-based adhesive film was adhered to one side of the substrate, and was made of plastic having a diameter of 125 μm using a pressing jig by ultrasonic vibration and an NC driven XY table. The optical fiber was laid in a circuit shape, and the optical fiber was extended to the outside of the outer shape of the base material to obtain a flexible base material. MC, a 0.8mm thick glass cloth / epoxy double-sided copper-clad laminate
After etching unnecessary portions of the surface copper foil of LE-679 (trade name, manufactured by Hitachi Chemical Co., Ltd.) to form a circuit, an IC chip, a chip resistor, a chip capacitor,
A chip transistor, etc. are mounted, and an acrylic rubber-based adhesive film with holes drilled on the mounted electronic parts is attached,
The optical fiber was placed and fixed there. Next, the signal extraction region of the optical fiber was cut from the surface to the bottom of the optical fiber by a dicing saw, and the optical fiber 4
Five cuts were obtained. Thereafter, an infrared laser was irradiated from the back surface of the substrate until a hole having a diameter of 0.3 mm reached the optical fiber. A laser light receiving element was attached to the side of the hole where the optical fiber was not fixed, and connected to a circuit on the surface to form a rigid substrate. A flexible substrate is superimposed on the rigid substrate manufactured in this manner, and an optical fiber fixed to the rigid substrate and an optical fiber provided to extend outside the flexible substrate intersect with each other, as shown in FIG. After pressing the intersection by the pressure welding device 2 having the groove 21 and ultrasonically vibrating, a fluorinated polyimide resin adhesive is added to the intersection with the dispenser 4 so that the tip of the dispenser 4 moves so as not to be caught by hot air. A hot air 5 was sent by a fan to fix both optical fibers 1. Since a flexible base material overlaps with the fiber laying surface, an optical circuit board having a fiber extension part of the flexible base material was manufactured without forming a protective film.

Example 4 A polyimide film having a thickness of 70 μm was used as a substrate, and an acrylic rubber-based adhesive film was adhered to one side of the substrate, and a 125 μm-diameter plastic made by a pressing jig using ultrasonic vibration and an XY table driven by an NC. An optical fiber was laid in a circuit shape, and the optical fiber was extended to connect with a connector outside the outer shape of the base material, thereby forming a flexible base material. A circuit is formed by etching away unnecessary portions of the surface copper foil of MCL-E-679 (trade name, manufactured by Hitachi Chemical Co., Ltd.) which is a 0.8 mm thick glass cloth / epoxy resin double-sided copper-clad laminate. After that, an IC chip, a chip resistor, a chip capacitor, a chip transistor, and the like were mounted thereon, and an acrylic rubber-based adhesive film having holes was applied to the mounted electronic components, and an optical fiber was mounted and fixed thereon. Next, the signal extraction region of the optical fiber was cut from the surface to the bottom of the optical fiber by a dicing saw, and a 45-degree cut surface of the optical fiber was obtained. afterwards,
Irradiate an infrared laser from the back of the substrate to 0.3mm in diameter
Holes were drilled until they reached the optical fiber. A laser light receiving element was attached to the side of the hole where the optical fiber was not fixed, and connected to a circuit on the surface to form a rigid substrate. On the rigid substrate thus produced, a flexible base material is overlaid, via a fluorinated polyimide resin-based adhesive,
The optical fiber fixed to the rigid substrate and the optical fiber laid on the flexible base material are crossed and aligned so that the optical fibers are in direct contact with each other. ,
While holding the intersection, hot air 5 was sent by a fan to connect and fix both optical fibers 1 via a polyimide film. Since the flexible base material overlaps the fiber laying surface, a multilayer optical circuit board having a fiber extension part to the connector by the flexible base material was manufactured without forming a protective film.

Example 5 Unnecessary portions of the surface copper foil of MCL-E-679 (trade name, manufactured by Hitachi Chemical Co., Ltd.), which is a 0.8 mm thick glass cloth / epoxy resin double-sided copper-clad laminate, are etched. This was removed to form a circuit. An acrylic rubber-based adhesive film was attached to the substrate on which this circuit was formed, and an optical fiber was mounted and fixed thereon. Next, the signal extraction region of the optical fiber was cut from the surface to the bottom of the optical fiber by a dicing saw, and a 45-degree cut surface of the optical fiber was obtained. After that, irradiate an infrared laser from the back surface of the substrate and drill a hole with a diameter of 0.3 mm until it reaches the optical fiber,
A rigid substrate was used. An acrylic rubber-based pressure-sensitive adhesive film was adhered to one surface of the base material with a pressure-sensitive adhesive on the surface, and the pressure was 70 μm.
A polyimide film base material having a thickness of m is adhered, and while a plastic optical fiber having a diameter of 125 μm is laid in a circuit shape by a pressing jig by ultrasonic vibration and an XY table (hereinafter referred to as a wiring machine) driven by NC, it is flexible. While extending the optical fiber to the outside of the base material, while fixing to the rigid substrate, the originally fixed optical fiber,
As shown in FIG. 2, the optical fiber 1 supplied from the optical fiber supply guide 3 is interposed between the optical fiber 1 provided from the optical fiber supply guide 3 and a press fitting 2 having a groove 21. The laser beam 6 was irradiated while applying pressure to establish connection. After curing, the fiber laying surface was coated with a flexible amide epoxy photosensitive resin having a thickness of 100 μm, vacuum degassed, and then cured by ultraviolet rays. This photosensitive resin layer formation was repeated twice to form a protective fixing layer of the fiber. Thereafter, an IC chip, a chip resistor, a chip capacitor, a chip transistor, and the like were mounted, a light receiving element was attached to the hole drilled from the back side, and an optical circuit board having a fiber extension portion made of a flexible base material was manufactured.

Example 6 A flexible substrate is placed on a flexible substrate on which a plastic optical fiber is fixed, and while the plastic optical fiber is placed in a circuit on the surface of the flexible substrate, the optical fiber extends to the outside of the flexible substrate. The optical fiber originally fixed and the optical fiber extended beyond the flexible substrate are crossed while fixing to the flexible substrate, and the energy by ultrasonic vibration is applied to the intersection. An optical circuit board having a fiber extension portion made of a flexible substrate was manufactured in the same manner as in Example 5, except that connection was performed while applying pressure.

[0034]

As described above, according to the present invention,
An optical circuit connection method for optical interconnection with a small area for optical connection and easy alignment between optical elements and optical fibers, and efficient production of optical circuit boards using such an optical circuit connection method Can provide a way to

[Brief description of the drawings]

FIG. 1 is a cross-sectional view for explaining a jig used in one embodiment of the present invention.

FIG. 2 is a cross-sectional view for explaining a jig used in another embodiment of the present invention.

[Explanation of symbols]

1. Optical fiber 2. Pressure welding tool 21. Groove 3. Optical fiber supply guide 4. Dispenser 5. Hot air 6. Laser light

Claims (17)

[Claims] 1. A method for connecting optical circuits, comprising: intersecting two plastic optical fibers, and applying pressure while applying energy by vibration to the intersection. 2. The method for connecting optical circuits according to claim 1, wherein the applied pressure is reduced from when the plastic optical fiber starts to deform. 3. The optical circuit connection method according to claim 1, wherein the crossing points are the ends of the respective plastic optical fibers. 4. The method for connecting optical circuits according to claim 1, wherein the energy due to the vibration is energy due to ultrasonic vibration. 5. The method according to claim 1, wherein the energy due to the vibration is energy due to a laser beam. 6. An optical fiber fixedly mounted on another rigid substrate, wherein the optical fiber is mounted and fixed on the surface of the flexible substrate in a circuit shape, and the optical fiber is provided so as to extend outside the flexible substrate. A method for manufacturing an optical circuit board, comprising intersecting an optical fiber provided to extend outside a base material and applying pressure while applying energy due to vibration to the intersection. 7. A flexible substrate is placed on a rigid substrate on which an optical fiber is fixed, and the optical fiber is extended to the outside of the flexible substrate while the optical fiber is placed in a circuit on the surface of the flexible substrate. While fixing to the rigid substrate, the optical fiber originally fixed and the optical fiber extended beyond the flexible base material are crossed and connected by applying pressure while applying energy by vibration to the intersection. A method for manufacturing an optical circuit board, comprising: 8. An optical fiber mounted and fixed on the surface of a flexible base material in a circuit form, and the optical fiber fixed to another rigid substrate and the optical fiber provided on the flexible base material are arranged so that the optical fibers are in direct contact with each other. A method of manufacturing an optical circuit board, comprising: overlapping, crossing optical fibers of each other, applying pressure while applying energy by vibration to the intersection, and connecting the optical fibers. 9. An optical fiber fixedly mounted on a surface of a flexible base material having a hole formed in advance at a place to be connected, the optical fiber being fixed in a circuit shape, the flexible base material and a rigid substrate being overlapped, and the optical fiber fixed to the rigid substrate; A method for manufacturing an optical circuit board, comprising intersecting an optical fiber provided on a flexible base material and applying pressure while applying energy due to vibration to an intersection thereof to connect the optical fiber. 10. An optical fiber fixedly mounted on another flexible substrate, wherein an optical fiber is mounted and fixed on the surface of a flexible substrate in a circuit form, and the optical fiber is provided so as to extend outside the flexible substrate. A method for manufacturing an optical circuit board, comprising intersecting an optical fiber provided to extend outside a base material and applying pressure while applying energy due to vibration to the intersection. 11. A flexible substrate is placed on a flexible substrate to which an optical fiber is fixed, and the optical fiber is extended to the outside of the flexible substrate while the optical fiber is placed in a circuit on the surface of the flexible substrate. While fixing to the flexible substrate, the optical fiber originally fixed and the optical fiber extended beyond the flexible base material are crossed, and pressure is applied while applying energy by vibration to the intersection to connect them. A method for manufacturing an optical circuit board, comprising: 12. An optical fiber mounted and fixed on the surface of a flexible substrate in a circuit form, and the optical fiber fixed to another flexible substrate and the optical fiber provided on the flexible substrate are so contacted that the optical fibers are in direct contact with each other. A method of manufacturing an optical circuit board, comprising: overlapping, crossing optical fibers of each other, applying pressure while applying energy by vibration to the intersection, and connecting the optical fibers. 13. An optical fiber is mounted and fixed in a circuit shape on a surface of a flexible base material in which holes are previously formed at connection points,
Overlay the flexible substrate and another flexible substrate, cross the optical fiber fixed to the flexible substrate and the optical fiber provided on the flexible substrate,
A method for manufacturing an optical circuit board, characterized in that a connection is made by applying pressure while applying energy by vibration to the intersection. 14. The method of manufacturing an optical circuit board according to claim 6, wherein the applied pressure is reduced from when the plastic optical fiber starts to deform. 15. The method of manufacturing an optical circuit board according to claim 6, wherein the crossing points are the ends of the respective plastic optical fibers. 16. The energy according to claim 6, wherein the energy due to vibration is energy due to ultrasonic vibration.
The method for manufacturing an optical circuit board according to any one of the above. 17. The method for manufacturing an optical circuit board according to claim 6, wherein the energy due to the vibration is energy due to a laser beam.