JP2010034103A - Optically coupled semiconductor relay - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an optically coupled semiconductor relay for mounting a photodetector and a switching element on the same substrate, which prevents the short circuit between the elements due to a spread conductive adhesive. <P>SOLUTION: The optically coupled semiconductor relay 10 has a structure in which the photodetector 12 and the switching elements 13, 13 are mounted using the conductive adhesive 1 on the conductive pattern 2 corresponding to each of the elements on the same substrate 21a, and the light-emitting element 11 is disposed oppositely to the photodetector 12. In the semiconductor relay, an insulative partitioning wall 31 is formed between the elements mounted on the substrate 21a. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to an improvement in an optically coupled semiconductor relay in which a light receiving element and a switching element are mounted on the same substrate.

  Conventional optically coupled semiconductor relays are known in which semiconductor elements are mounted on a substrate or a lead frame, and a conductive adhesive is used to bond the elements to them, and between elements, elements, It is customary to electrically connect between conductive patterns with wires.

  This type of optically coupled semiconductor relay is a device in which elements and the like are arranged in a minute space, and in order to maintain their insulation, it is sufficient for element arrangement and wire connection in design and manufacturing. Attention has been paid.

In general, an element mounted on a lead frame has a structure in which elements are arranged in isolation, so that there is almost no possibility that the elements are short-circuited when the conductive adhesive spreads more than necessary. Moreover, in the thing of patent document 1, the insulating property is further improved using the insulating film.
Japanese Utility Model Publication No. 5-28059

  However, in a semiconductor relay in which a plurality of elements are mounted on the same substrate, the conductive pattern is separated on the substrate, but the paste-like conductive adhesive for bonding the elements to the substrate spreads before curing. This may cause a short circuit between the elements.

  FIG. 5 is a longitudinal sectional view of a box-type semiconductor relay in which a light receiving element and a switching element are mounted on the same substrate. As shown in this figure, both conductive patterns 102 on the substrate 110 on which the light receiving element 112 and the switching element 113 are mounted are close to each other, and there is no barrier between them. If the agent 101 flows and spreads, it will contact easily and short-circuit. In the figure, 111 is a light emitting element, 103 is a bonding wire, 104 is a through hole, and 105 is a conductive pattern formed outside the box.

  Therefore, conventionally, in order to avoid such a situation, the elements are arranged at a safe distance so as not to contact each other even if the conductive adhesive spreads. In particular, the substrate-mounting type semiconductor relay has a problem of insulation regarding the light receiving element and the switching element mounted on the same substrate.

  The present invention has been proposed in view of such a problem, and the object thereof is to mount a light receiving element and a switching element on the same substrate, and the conductive adhesive spreads to cause a short circuit between the elements. An object of the present invention is to provide an optically coupled semiconductor relay that can prevent this.

  In order to achieve the above object, the optically coupled semiconductor relay according to claim 1, wherein the light receiving element and the switching element are mounted on a conductive pattern corresponding to each element on the same substrate using a conductive adhesive. In the optically coupled semiconductor relay in which the light emitting element is disposed facing the light receiving element, an insulating partition wall is formed between the elements mounted on the substrate.

  According to a second aspect of the present invention, there is provided the optical coupling type semiconductor relay according to the first aspect, wherein the partition wall is formed with a through-hole in the wall that vertically penetrates the wall and communicates with the conductive pattern on the substrate from the upper end portion. Has been.

  The optically coupled semiconductor relay according to claim 3, wherein the light receiving element and the switching element are mounted on a conductive pattern corresponding to each element on the same substrate using a conductive adhesive, and facing the light receiving element. In an optically coupled semiconductor relay in which a light emitting element is arranged, an insulating partition groove is formed between elements mounted on a substrate.

In the optically coupled semiconductor relay in which the light receiving element and the switching element are mounted on a conductive pattern corresponding to each element on the same substrate using a conductive adhesive, and the light emitting element is disposed opposite to the light receiving element.
The optically coupled semiconductor relay according to claim 3, wherein the light receiving element and the switching element are mounted on a conductive pattern corresponding to each of the elements on the same substrate using a conductive adhesive, and are opposed to the light receiving element. In the optically coupled semiconductor relay in which the light emitting elements are arranged, the conductive pattern corresponding to each element on the same substrate is formed on an insulating base in which a through hole is formed so as to be conductive from the conductive pattern to the substrate side. It is characterized by being.

  According to the optically coupled semiconductor relay according to claim 1, since the partition wall is provided between the elements, even if the paste-like conductive adhesive flows, the adjacent element and its conductive pattern that crosses the partition wall. There is no risk of contact with the conductive adhesive, and a short circuit between the elements can be prevented.

  According to the optically coupled semiconductor relay of the second aspect, since the through-hole in the wall is formed in the partition wall, wire bonding can be performed on the upper end of the through-hole in the wall. In this way, wire bonding can be performed on the upper end of the partition wall located higher than the bottom, so that bonding work in a minute space can be easily performed without fear of a short circuit.

  According to the optically coupled semiconductor relay according to claim 3, since the partition groove is provided between the elements, the adhesive spreading through the partition groove can be dammed, and the element adjacent to the conductive adhesive or its There is no risk of contact with the conductive pattern and conductive adhesive, and short circuit can be prevented.

  According to the optically coupled semiconductor relay according to claim 4, since the conductive pattern is formed at a high position by the pedestal, the conductive adhesive may come into contact with the adjacent element, the conductive pattern, or the conductive adhesive. The short circuit between elements can be prevented.

  In addition, since these optically coupled semiconductor relays of the present invention have a structure that blocks the spread of the conductive adhesive by various partitions, it is considered that a plurality of elements mounted on the substrate are spread by the adhesive. Therefore, it is not necessary to arrange them separately, which can contribute to the miniaturization of the relay.

  Embodiments of the present invention will be described below with reference to the accompanying drawings. The substrate-type optically coupled semiconductor relay described below is a multilayer substrate made of ceramics or the like packaged in a box shape. However, the present invention is not limited to this, and a printed circuit board may be used. Further, a case-type optically coupled semiconductor relay (hereinafter, abbreviated as a semiconductor relay) shown in each figure has a bottomed box 21 in which a light receiving element 12 and a switching element 13 are mounted at the bottom, and a light emitting element 11. It consists of a lid 22.

  1A and 1B are explanatory views of the structure of a semiconductor relay according to a first embodiment of the present invention. FIG. 1A is a longitudinal sectional view, and FIG. 1B is a plan view of a box.

  The semiconductor relay 10 is configured by mounting a light emitting element 11, a light receiving element 12, and a switching element 13 on each substrate on which a conductive pattern is formed, and combining them. The light emitting side substrate 22a is formed on the lid body 22, and the light receiving side substrate 21a is formed on the bottom portion 21a of the box body 21 opened upward. The box body 21 is covered with a lid 22 to form a sealed casing 20, and an optical coupling space 23 is formed inside the casing 20. Note that the light coupling space 23 in the housing 20 may be filled with a translucent resin having a low impurity content.

  The conductive patterns 2 and 4 are formed on the inner side and the outer side of the substrate 21a constituting the bottom portion of the box body 21, and are connected so as to be conductive through a through hole 21c in which the inner surface of the hole is plated. ing. In FIG. 1, the conductive patterns and through holes connected to the light emitting element 11 are not shown (the same applies to FIGS. 2 to 4 described later).

  The light emitting element 11 is made of a light emitting diode or the like, and the light receiving element 12 is made of a photodiode or the like. The switching element 13 is a semiconductor element such as a MOSFET that is turned on and off based on an output signal of the light receiving element 12. In the illustrated example, two switching elements 13 are mounted.

  These semiconductor elements have electrodes (not shown) on the upper surface and the back surface, and the electrodes on the back surface are bonded to the conductive pattern 2 on the substrate 21a with a conductive adhesive 1 such as a silver paste. The conductive adhesive 1 is not shown in FIG. 1 (a). The upper electrode is connected to the upper electrode of another element and the conductive pattern 2 on the substrate 21a through the bonding wire 3.

  A partition wall 31 that partitions the light receiving element 12 and the two switching elements 13 and 13 individually is formed on the bottom substrate 21a of the box 21 of the semiconductor relay 10. The partition wall 31 is made of an insulating material such as resin.

  Thus, since each element 12,13,13 is partitioned off by the insulating partition wall 31, even if it is the paste state before hardening, the conductive adhesive 1 flows over the partition wall 31. Therefore, there is no possibility that the conductive adhesive 1 is in contact with the adjacent element, its conductive pattern 2, or the conductive adhesive 1, and a short circuit between the elements can be prevented.

  2A and 2B are explanatory views of the structure of the semiconductor relay according to the second embodiment of the present invention. FIG. 2A is a longitudinal sectional view and FIG. 2B is a plan view of a box.

  Also in the semiconductor relay 10 of this embodiment, an insulating partition wall 31 is formed at a position in the same manner as in the first embodiment. Among these partition walls 31, those for partitioning the light receiving element 12 and the switching element 13 are formed with in-wall through holes 31 a penetrating vertically through the walls.

  The upper end portion of the in-wall through hole 31a is connected to the upper surface electrode of the switching element 13 by the wire 3, and is formed on the switching element 13 and the bottom substrate 21a on the light receiving element 12 side through the in-wall through hole 31a. The conductive pattern 2 is connected to be conductive.

  As described above, in this embodiment, the wire 3 may be bonded to the upper end portion of the partition wall 31 at a position higher than the conductive pattern 2 formed on the bottom portion 21a. Therefore, the bonding work using a capillary (capillary tube) or the like can be performed with high accuracy and efficiency without being disturbed by the peripheral wall 21b or the like as compared with bonding to the bottom 21a.

  In order to facilitate bonding, it is desirable to form a conductive pattern on the upper end surface of the partition wall 31 so as to communicate with the through-hole 31a in the wall. Moreover, it is better to form the partition wall 31 as high as possible.

  Since other configurations in the second embodiment are the same as those in the first embodiment, the same reference numerals are given and description thereof is omitted.

  3A and 3B are explanatory views of the structure of a semiconductor relay according to a third embodiment of the present invention. FIG. 3A is a longitudinal sectional view, and FIG. 3B is a plan view of a box.

  In the semiconductor relay 10 of this embodiment, a partition groove 32 is formed at the same position as the partition wall shown in the first embodiment. The inner surface of the partition groove 32 is insulated. If the substrate 21a is made of an insulating material, the inner surface of the groove may not be insulated if the substrate 21a is scraped to form the partition groove 32.

  In this way, since each element is partitioned by the insulating partition groove 32, the conductive adhesive 1 flowing through the partition groove 32 can be dammed up, and the conductive adhesive 1 can be connected to the adjacent element or its element. The possibility of contact with the conductive pattern 2 and the conductive adhesive 1 is low, and a short circuit between elements can be prevented. Further, the partition grooves may be doubled so that the conductive adhesive 1 of both elements does not contact within the partition groove 32. Moreover, you may provide a partition in a partition groove.

  Since other configurations in the third embodiment are the same as those in the first embodiment, the same reference numerals are given and description thereof is omitted.

  4A and 4B are explanatory views of the structure of a semiconductor relay according to a fourth embodiment of the present invention. FIG. 4A is a longitudinal sectional view and FIG. 4B is a plan view of a box.

  In the present embodiment, two switching elements 13 are mounted on the bottom substrate 21a via an insulating pedestal 33. The pedestal 33 has a conductive pattern 2 formed on its upper surface and a through hole 33a that communicates with the conductive pattern 2. The through hole 33a communicates with the through hole 21c of the substrate 21a. That is, the back electrode of the switching element 13 is electrically connected to the external conductive pattern 4 through the through holes 33a and 21c of the base 33 and the substrate 21a.

  In this way, the conductive pattern 2 is formed on the pedestal 33, and the element 13 is stuck on the conductive adhesive 1 on the pedestal 33. The distance to the conductive pattern 2 and the conductive adhesive 1 is increased, and a short circuit between elements can be prevented.

  In the example of FIG. 4, the pedestal 33 is provided for the two switching elements 13 out of the three elements, but a pedestal may be provided for the light receiving element 12 in order to enhance the damming effect.

  Since the other configuration of the fourth embodiment is the same as that of the first embodiment, the same reference numerals are given and description thereof is omitted.

  The example in which the partition wall 31, the partition wall 31 with a through hole, the partition groove 32, and the pedestal 33 are used as means for preventing the spread of the conductive adhesive 1 has been shown above. Also good.

  In addition, since the semiconductor relay described above has a structure that blocks the spreading of the conductive adhesive 1 by various partitioning means, a plurality of elements mounted on the substrate are taken into consideration that the conductive adhesive 1 spreads. There is no need to arrange them apart, and the relay can be miniaturized.

BRIEF DESCRIPTION OF THE DRAWINGS It is structure explanatory drawing of the optical coupling type semiconductor relay which shows the 1st Embodiment of this invention, (a) is a longitudinal cross-sectional view, (b) is a top view of a box. It is structure explanatory drawing of the optical coupling type semiconductor relay which shows the 2nd Embodiment of this invention, (a) is a longitudinal cross-sectional view, (b) is a top view of a box. It is structure explanatory drawing of the optical coupling type semiconductor relay which shows the 3rd Embodiment of this invention, (a) is a longitudinal cross-sectional view, (b) is a top view of a box. It is structure explanatory drawing of the optical coupling type semiconductor relay which shows the 4th Embodiment of this invention, (a) is a longitudinal cross-sectional view, (b) is a top view of a box. It is structure explanatory drawing of the conventional optical coupling type semiconductor relay, (a) is a longitudinal cross-sectional view, (b) is a top view of a box.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Optical coupling type semiconductor relay 11 Light emitting element 12 Light receiving element 13 Switching element 20 Case 21 Box 21a Bottom part (light receiving side board | substrate)
21b Peripheral wall 21c Through hole 22 Lid 22a Light emission side substrate 23 Optical coupling space 31 Partition wall 31a Through hole 31b Upper end 32 Partition groove 33 Base 33a Through hole 1 Conductive adhesive 2 Conductive pattern (on substrate)
3 Bonding wire 4 Conductive pattern (outside)

Claims (4)

In an optically coupled semiconductor relay in which a light receiving element and a switching element are mounted on a conductive pattern corresponding to each element on the same substrate using a conductive adhesive, and a light emitting element is disposed opposite to the light receiving element. ,
An optically coupled semiconductor relay, wherein an insulating partition wall is formed between elements mounted on the substrate. In claim 1,
An optically coupled semiconductor relay, wherein the partition wall is formed with an in-wall through-hole penetrating up and down in the wall so as to be conductive from the upper end portion to the conductive pattern on the substrate. In an optically coupled semiconductor relay in which a light receiving element and a switching element are mounted on a conductive pattern corresponding to each element on the same substrate using a conductive adhesive, and a light emitting element is disposed opposite to the light receiving element. ,
An optically coupled semiconductor relay, wherein an insulating partition groove is formed between elements mounted on the substrate. In an optically coupled semiconductor relay in which a light receiving element and a switching element are mounted on a conductive pattern corresponding to each element on the same substrate using a conductive adhesive, and a light emitting element is disposed opposite to the light receiving element. ,
The conductive pattern corresponding to each element on the same substrate is formed on an insulating base in which a through hole is formed so as to be conductive from the conductive pattern to the substrate side. Semiconductor relay.

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