JP2006317598A - Electro-optical conversion module and method of manufacturing substrate therefor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an electro-optical conversion module capable of improving productivity and assembly properties and reducing manufacturing costs. <P>SOLUTION: A lower substrate 10, an intermediate substrate 20, and an upper substrate 30 are laminated in order from the lower side. The lower substrate 10 includes a light reception/emission element 50 mounted on the upper surface thereof, conductor patterns 41, 42 and so forth for conducting the light reception/emission element 50 to the outside, and insertion through-holes 12 which are formed in the direction of the substrate thickness and through which positioning pins 60 are inserted. The intermediate substrate 20 includes an accommodation hole 21 accommodating the light reception/emission element 50, and insertion through-holes 22 which are formed in the thickness direction of the substrate and through which the positioning pins 60 are inserted. The upper substrate 30 includes a through-hole 31 which is formed in the thickness direction of the substrate and through which an optical fiber 70 is inserted and insertion through-holes 32 which are formed in the thickness direction of the substrate and through which the positioning pins 60 are inserted. The front end face 71 of the optical fiber 70 is disposed opposite to the light reception/emission element 50. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to an electrical / optical conversion module for coupling an optical fiber and a light emitting / receiving element, and a substrate manufacturing method for the module.

  In optical communication, an electric / optical conversion module that converts electricity into light or light into electricity is used. It is extremely important to minimize the output loss in this electrical / optical conversion module. To that end, the optical axis between the optical fiber as the transmission medium and the light receiving / emitting element of the electrical / optical conversion medium is determined. It needs to be matched precisely.

  For example, two flat plates with insertion holes formed in the plate thickness direction are arranged in parallel, an optical fiber is inserted through the insertion holes to hold the optical fiber in a predetermined direction, and penetrates the flat plate. Electrical / optical conversion configured to match the tip surface of the optical fiber with the light emitting / receiving element by bonding the alignment pin provided to the light receiving / emitting element holding member on which the light receiving / emitting element is mounted. Modules have been proposed (see, for example, Patent Document 1).

  In the electrical / optical conversion module of Patent Document 1, an optical fiber insertion hole and an alignment pin penetration hole are formed with photolithography accuracy (about 0.1 μm), and the light receiving and emitting element holding In the member, a light receiving / emitting element and a recess for receiving the alignment pin are also formed with an accuracy of photolithography.

For this reason, in the electrical / optical conversion module of Patent Document 1, the two flat plates and the light emitting / receiving element holding member can be joined with sufficient accuracy, and the joining is a fitting type, so that the removal is easy. It has become.
JP 2000-266965 A

  However, in the conventional electrical / optical conversion module, a spacer is provided between two flat plates, and a semiconductor substrate is provided on the light receiving and emitting element holding member. Since the recess for receiving the alignment pin is formed, each part having many different shapes is required, and it is difficult to improve productivity and assembly.

  In addition, in the conventional electric / optical conversion module, each part is formed by making full use of the photolithography method, so that the accuracy can be extremely high, but the manufacturing cost of the module increases.

  An object of the present invention is to provide an electrical / optical conversion module capable of improving productivity and assembling performance and capable of reducing manufacturing costs, and a method of manufacturing a substrate for the module.

In order to solve the above-mentioned problem, the invention according to claim 1 is such that a lower substrate, a middle substrate, and an upper substrate are laminated in order from the bottom,
The lower substrate includes a light emitting / receiving element mounted on an upper surface thereof, a conductor pattern for electrically connecting the light emitting / receiving element and the outside, and an insertion hole formed in a plate thickness direction through which a positioning pin is inserted. ,
The intermediate substrate has a receiving hole in which the light emitting / receiving element is accommodated, and an insertion hole formed in the plate thickness direction through which the positioning pin is inserted,
The upper substrate has a through hole formed in the plate thickness direction through which an optical fiber is inserted, and an insertion hole formed in the plate thickness direction through which the positioning pin is inserted.
The tip surface of the optical fiber is arranged to face the light emitting / receiving element.

  According to the above configuration, the lower substrate, the middle substrate, and the upper substrate can be manufactured from one base substrate. For example, the lower substrate, the middle substrate, and the upper substrate are set in advance on the base substrate, the positioning pin insertion holes are provided in the lower substrate portion, and the light receiving and emitting elements are accommodated in the middle substrate portion. And a hole for inserting a positioning pin, and a portion for forming a lower substrate, in which a through hole for inserting an optical fiber and a through hole for inserting a positioning pin are formed in the plate thickness direction in a portion to be an upper substrate, respectively. The lower substrate, the middle substrate, and the upper substrate can be manufactured by dividing the portion to be the middle substrate and the portion to be the upper substrate from the base substrate. As a result, it becomes possible to improve the productivity and assembly of the electrical / optical conversion module.

  According to a second aspect of the present invention, in the first aspect, the lower substrate, the middle substrate, and the upper substrate have the same thickness.

  According to a third aspect of the present invention, in the second aspect, the plate thickness is such that a light emitting / receiving element mounted on the lower substrate and a wire thereof do not interfere with the upper substrate, and a space is formed in the middle substrate. It is characterized by being set to the minimum thickness of the intermediate substrate to be obtained.

  According to a fourth aspect of the present invention, in the first aspect, the lower substrate is formed with a through hole in a plate thickness direction, and an inner surface of the through hole is plated, and is formed on the upper surface of the lower substrate. The conductor pattern and the conductor pattern formed on the lower surface of the lower substrate are electrically connected through a plated portion on the inner surface of the through hole.

  According to a fifth aspect of the present invention, in the fourth aspect, the lower substrate protrudes outward from the middle substrate, an outer through hole is formed in the protruding portion, and an outer conductor pattern is formed on the upper surface of the protruding portion. The outer conductor pattern is electrically connected to the conductor pattern formed on the lower surface of the lower substrate through the plated portion on the inner surface of the outer through hole.

  A sixth aspect of the invention is characterized in that in any one of the first to fifth aspects, a plurality of the upper substrates are laminated.

  The invention according to claim 7 is an invention of a substrate manufacturing method for an electrical / optical conversion module, wherein a lower substrate, a middle substrate, and respective portions to be an upper substrate are set in advance on a base substrate to form a lower substrate. Positioning holes for positioning pins in the part, receiving holes for receiving light emitting and receiving elements and insertion holes for positioning pins in the part to be the middle substrate, positioning through holes for inserting optical fibers in the part to be the upper substrate The through holes for pin insertion are collectively formed in the plate thickness direction, and the lower substrate, the portion serving as the middle substrate, and the portion serving as the upper substrate are allocated from the base substrate, A middle substrate and an upper substrate are manufactured, respectively.

  According to the present invention, it is possible to improve the productivity and assembly of the electric / optical conversion module, and as a result, it is possible to reduce the manufacturing cost of the electric / optical conversion module.

  Embodiments of the present invention will be described below with reference to the drawings.

  FIG. 1 is a longitudinal sectional view of an electrical / optical conversion module according to the present invention. In this electrical / optical conversion module 1, a lower substrate 10, a middle substrate 20, and an upper substrate 30 are laminated in order from the bottom.

  The lower substrate 10 is formed with a conductor pattern 40 (see FIG. 3, which is usually shaped to match the shape of the light emitting / receiving element 50) in the center of the upper surface. A light emitting element 50 is mounted. In the lower substrate 10, through holes 11 and 11 are formed on both sides of the conductor pattern 40 along the thickness direction of the lower substrate 10. Then, ring-shaped conductor patterns 41 and 41 (see FIG. 3) are formed around the upper opening ends of the through holes 11 and 11 on the upper surface of the lower substrate 10, and one of the conductor patterns 41 and the light emitting and receiving element 50. Are connected by a wire 51. The other conductor pattern 41 is connected to the conductor pattern 40 via the connection pattern 40A.

  On the lower surface of the lower substrate 10, ring-shaped conductor patterns 42 and 42 are formed around the lower opening end of the through hole 11, and the conductor patterns 42 and 42 and the conductor patterns 41 and 41 correspond to the through holes 11 and 11. It is electrically connected through plated portions 43, 43 provided on the inner surfaces.

  The lower substrate 10 is formed with insertion holes 12 and 12 outside the through holes 11 and 11, and positioning pins 60 and 60 are inserted into the insertion holes 12 and 12, respectively.

  For example, a circular accommodation hole 21 is formed in the middle portion of the middle substrate 20. In addition, insertion holes 22 and 22 are formed on the outer side of the accommodation hole 21 in the middle substrate 20, and positioning pins 60 and 60 are inserted into the insertion holes 22 and 22, respectively. The inner diameters of the insertion holes 22 and 22 are set to be slightly larger than the inner diameters of the insertion holes 12 and 12 of the lower substrate 10, and the positioning pins 60 and 60 are inserted into the insertion holes 22 and 22 in a loosely fitted state. .

  The upper substrate 30 is formed with a through hole 31 at the center thereof, and an optical fiber 70 is inserted into the through hole 31 from above. The tip surface 71 of the optical fiber 70 is adjusted to be flush with the lower surface of the upper substrate 30. Further, the upper substrate 30 is formed with insertion holes 32 and 32 outside the through-hole 31, and the positioning pins 60 and 60 are inserted into the insertion holes 32 and 32, respectively. The inner diameters of the insertion holes 32 and 32 are set to be the same as the insertion holes 12 and 12 of the lower substrate 10.

  By stacking the lower substrate 10, the middle substrate 20, and the upper substrate 30, the upper and lower sides of the accommodation hole 21 of the middle substrate 20 are closed, and a space 23 is formed inside the accommodation hole 21. The wire 51 is disposed in the space 23.

  Here, the lower substrate 10, the middle substrate 20, and the upper substrate 30 are manufactured as follows. First, as shown in FIG. 2, a vertically long rectangular base substrate 80 made of glass epoxy resin is prepared, and a portion that becomes a lower substrate 10 is considered on this base substrate 80 by dividing into three equal areas as indicated by broken lines. 10 ′, a portion 20 ′ to be the middle substrate 20, and a portion 30 ′ to be the upper substrate 30 are set. Then, with respect to the portion 10 ′ to be the lower substrate 10, copper foil conductive patterns 40, 41, and the same pattern on the lower surface are matched to a reference mark (not shown) by a known printed wiring board manufacturing method or the like. 42 is formed accurately.

  Next, the through holes 11, 11, the insertion holes 12, 12, the accommodation holes 21, the insertion holes 22, 22, the through holes 31, and the insertion holes 32, 32 are applied to the base substrate 80 by a press die (not shown). Is formed at once. Also in this case, of course, the holes are accurately processed according to a reference mark (not shown), and the relative positional relationship between the conductor patterns 40, 41, and 42 and the holes is maintained with extremely high accuracy. Moreover, since each said hole is formed at once, the relative positional relationship of each hole will not go out of order.

  Subsequently, a known plating process is performed on the base substrate 80 in order to form the plated portion 43 on the inner surface of the through hole 11. Finally, the lower substrate 10, the middle substrate 20, and the upper substrate 30 can be obtained by cutting the base substrate 80 that has been subjected to these processes with a cut line indicated by a broken line in FIG. 2.

  After the lower substrate 10, the middle substrate 20, and the upper substrate 30 are obtained, the light emitting / receiving element 50 is accurately positioned and mounted in a predetermined position on the conductor pattern 40 of the lower substrate 10 by a known means in advance. The wire 51 is connected on the conductor pattern 41. In addition, the optical fiber 70 is fitted into the through hole 31 of the upper substrate 30, and the distal end surface 71 thereof is matched with the lower surface of the upper substrate 30, and then the optical fiber 70 is fixed to the lower substrate 30 using an adhesive. deep.

  Then, the positioning pin 60 is fitted into the insertion hole 32 of the upper substrate 30, the middle substrate 20 is arranged below the upper substrate 30, the positioning pin 60 is inserted into the insertion hole 22, and then the middle The lower substrate 10 is disposed under the substrate 20 and the positioning pins 60 are fitted into the insertion holes 12.

  Finally, the lower substrate 10 and the middle substrate 20 are bonded with an adhesive, and the middle substrate 20 and the upper substrate 30 are bonded with an adhesive. Thus, the electrical / optical conversion module 1 with the exact matching is completed.

  In the present embodiment, the base substrate 80 has been described with an example in which each of the portion 10 ′ serving as the lower substrate 10, the portion 20 ′ serving as the middle substrate 20, and the portion 30 ′ serving as the upper substrate 30 is provided. However, each of these parts 10 ', 20', 30 'is large with several tens and hundreds, and each hole 10 is processed at once, so that each part 10', 20 ', 30' has a large amount. It is also possible to produce.

  In addition, the manufacturing procedure has been described as providing the holes 11, 12, 21, 22, 31, 32, etc. after the formation of the conductor patterns 40, 41, 42, but for the large base substrate as described above, Each of the holes is formed at once, and only the portion 20 ′ (the portion that becomes the middle substrate 20) and the portion 30 ′ (the portion that becomes the upper substrate 30) are allocated from the base substrate, that is, the portion 10 ′ ( The portions to be the lower substrate 10) are kept continuous, and the conductor patterns 40, 41, 42 and the plated portion 43 are formed on the continuous portion 10 ′ by a known means, and then the portion 10 ′ is formed. Each of the lower substrates 10 may be divided.

  Further, in this embodiment, the base substrate 80 is formed with the same number (one) of the portion 10 ′ serving as the lower substrate 10, the portion 20 ′ serving as the middle substrate 20, and the portion 30 ′ serving as the upper substrate 30. However, the present invention is not limited to this. For example, only the portion 30 ′ to be the upper substrate 30 may be prepared twice or five times as much as the other portions 10 ′ and 20 ′. Then, when the middle substrate 20 is laminated on the lower substrate 10, two or five layers of the upper substrate 30 are laminated on the middle substrate 20.

  In this way, the length of the through hole 31 can be substantially increased, and the attachment of the optical fiber 70 can be further stabilized.

  In addition, the thickness of the base substrate 80, in other words, the thickness T of the middle substrate 20 may be selected as follows. That is, as shown in FIG. 1, the clearance C between the top surface 52 of the light emitting / receiving element 50 mounted on the lower substrate 10 and the tip 71 of the optical fiber 70 set in the through hole 31 is used for light energy transfer. In order to be optimal, that is, after ensuring the height of the light emitting / receiving element 50 and the height required for the handling of the wire 51, the thickness C is selected so that the clearance C becomes the minimum.

  If it does so, the electrical / optical module 1 can be easily assembled only by laminating | stacking three board | substrates 10, 20, and 30 like FIG. 1, and adjustment of the said clearance C is not required.

  In the present embodiment, a known printed wiring board manufacturing technique is described as a means for forming the conductor patterns 40, 41, and 42, and a press die is used for drilling. This method is also possible.

  As described above, according to the present embodiment, the through hole 11 and the insertion hole 12 of the lower substrate 10, the accommodation hole 21 and the insertion hole 22 of the middle substrate 20, and the through hole 31 and the insertion hole 32 of the upper substrate 30 are formed. Since they are formed all at once, the relative positional relationship between the holes is strictly maintained. By inserting the positioning pin 60 into the insertion holes 12, 22, and 32, the deviation between the substrates 10, 20, and 30 is eliminated. It can be easily extinguished. At the same time, the conductor pattern 40 prepared on the lower substrate 10 is strictly positioned, and the substrate 10, 20, 30 is laminated because the light receiving / emitting element 50 is mounted accurately positioned there. Thus, the optical axis alignment between the light emitting / receiving element 50 and the optical fiber 70 can be strictly performed automatically. As a result, an electrical / optical conversion module with little output loss can be realized.

  Further, according to this embodiment, since the members constituting the electrical / optical conversion module are extremely few and simple, an inexpensive electrical / optical conversion module can be provided.

  Furthermore, since it is not necessary to use an advanced construction method for the conductor pattern and each hole processing, productivity and assemblability can be improved and manufacturing cost can be suppressed.

  Next, a second embodiment of the present invention will be described with reference to FIGS. In the present embodiment, one side of the lower substrate 10 protrudes to the side of the middle substrate 20, and the outer through hole 16 is formed in the protruding portion 15. A ring-shaped outer conductor pattern 45 is formed around the upper open end of the outer through-hole 16, and a ring-shaped outer conductor pattern 46 is formed around the lower open end of the through-hole 16. The outer conductor pattern 46 is electrically connected by a plated portion 47 provided on the inner surface of the outer through hole 16. The outer conductor pattern 46 is electrically connected to the conductor pattern 42 via a connection pattern 48 formed on the lower surface of the lower substrate 10.

  According to the present embodiment, an electrical signal can be taken out from the upper surface of the lower substrate 10 through the connection pattern 48, the outer conductor pattern 46, the plated portion 47, and the outer conductor pattern 45. Further, since the protruding portion 15 is provided on the lower substrate 10, an electronic component such as an IC can be mounted on the protruding portion 15.

It is a longitudinal cross-sectional view of the electrical / optical conversion module by Example 1 of this invention. It is a top view of the base substrate used for the electrical / optical conversion module of FIG. It is the A section enlarged view of FIG. It is a longitudinal cross-sectional view of the electrical / optical conversion module by Example 2 of this invention. It is a top view of the base substrate used for the electrical / optical conversion module of FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Electricity / optical conversion module 10 Lower board | substrate 11 Through-hole 12, 22, 32 Insertion hole 15 Protruding part 16 Outer through-hole 20 Middle board | substrate 21 Accommodating hole 30 Upper board | substrate 31 Through-hole 40, 41, 42 Conductor pattern 43, 47 Plating part 45, 46 Outer conductor pattern 48 Connection pattern 50 Light emitting / receiving element 60 Positioning pin 70 Optical fiber

Claims (7)

A lower substrate, a middle substrate and an upper substrate are laminated in order from the bottom,
The lower substrate includes a light emitting / receiving element mounted on an upper surface thereof, a conductor pattern for electrically connecting the light emitting / receiving element and the outside, and an insertion hole formed in a plate thickness direction through which a positioning pin is inserted. ,
The intermediate substrate has a receiving hole in which the light emitting / receiving element is accommodated, and an insertion hole formed in the plate thickness direction through which the positioning pin is inserted,
The upper substrate has a through hole formed in the plate thickness direction through which an optical fiber is inserted, and an insertion hole formed in the plate thickness direction through which the positioning pin is inserted.
An electrical / optical conversion module, wherein a front end surface of the optical fiber is arranged to face the light emitting / receiving element.   The electric / optical conversion module according to claim 1, wherein the lower substrate, the middle substrate, and the upper substrate have the same thickness.   The plate thickness is set to a minimum thickness of the middle substrate that can form a space on the middle substrate, in which the light emitting and receiving elements and the wires mounted on the lower substrate do not interfere with the upper substrate. The electrical / optical conversion module according to claim 2.   A through hole is formed in the lower substrate in the thickness direction, and an inner surface of the through hole is plated, and a conductor pattern formed on the upper surface of the lower substrate and a conductor pattern formed on the lower surface of the lower substrate The electrical / optical conversion module according to claim 1, wherein is electrically connected through a plated portion on the inner surface of the through hole.   The lower substrate protrudes outward from the middle substrate, an outer through hole is formed in the protruding portion, and an outer conductor pattern is formed on the upper surface of the protruding portion, and the outer conductor pattern is formed on the inner surface of the outer through hole. The electrical / optical conversion module according to claim 4, wherein the electrical / optical conversion module is electrically connected to a conductor pattern formed on a lower surface of the lower substrate through a plating portion.   The electrical / optical conversion module according to claim 1, wherein a plurality of the upper substrates are stacked. On the base substrate, each part to be the lower substrate, middle substrate and upper substrate is set in advance,
Positioning pin insertion holes in the lower substrate portion, receiving and emitting element accommodating holes and positioning pin insertion holes in the middle substrate portion, and optical fiber insertion holes in the upper substrate portion The through holes for inserting the through holes and the positioning pins are formed together in the thickness direction, respectively,
Electrical / optical conversion characterized in that a lower substrate, a middle substrate, and an upper substrate are manufactured by dividing a portion to be a lower substrate, a portion to be a middle substrate, and a portion to be an upper substrate from the base substrate, respectively. A substrate manufacturing method for modules.

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