JP2008182155A - Optical-coupling semiconductor relay - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an optical-coupling semiconductor relay with an easy manufacturing method, an excellent accuracy in size between elements, and a small and thin configuration. <P>SOLUTION: The optical-coupling semiconductor relay 1 has a light emitter 3, a light receiver 4 oppositely disposed to the light emitter 3, and a switching element 5 receiving an output from the light receiver 4. These elements are mounted in the inner space of a housing 2 having an opening 2c. The housing 2 has a recess 2b formed in an inner bottom 2a, the light emitter 3 is mounted in the recess 2b in a flip-chip structure, and the light receiver 4 is in the flip-chip structure across the recess 2b with its light receiving side inclined downward. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to an improvement in an optically coupled semiconductor relay configured by mounting a light emitting element and a light receiving element in a housing.

Conventionally, various optically coupled semiconductor relays excellent in electrical isolation have been proposed and employed in various applications.
FIG. 7 is a longitudinal sectional view showing an example of a conventional optically coupled semiconductor relay using a lead frame.

  In this semiconductor relay 100, a light emitting element 103 and a light receiving element 104 provided on each of the lead frames 101 and 102 are arranged to face each other, and a light transmitting space is formed by filling a translucent resin 106 so that external light enters. In order to prevent this, it is sealed with a light shielding resin 107 such as black. In order to form an energization path, the light emitting element 103, the light receiving element 104, and the switching element 105 are die-bonded on the lead frames 101 and 102 and further bonded by a wire 109.

Further, the semiconductor relay shown in the following Patent Document 1 has a light emitting element and a light receiving element mounted on a substrate instead of a lead frame. The substrate is provided with a recess, and the light emitting element is mounted in the recess. Is arranged so as to face the light emitting element so as to straddle the concave portion, and the light receiving element is flip-chip mounted, thereby reducing the size and thickness and improving the dimensional accuracy between the elements.
JP 2001-326381 A

  However, the conventional device has a problem that it takes time to manufacture because at least the light emitting element is configured to be wired with a metal wire.

  The present invention has been proposed to solve such problems, and an object thereof is to provide an optically coupled semiconductor relay that is easy to manufacture, has good dimensional accuracy between elements, and can be reduced in size and thickness. It is said.

  In order to achieve the above object, an optically coupled semiconductor relay according to claim 1 includes a light emitting element, a light receiving element disposed in a state facing the light emitting element, and a switching element that receives an output from the light receiving element. Is mounted in the inner space of the housing having an opening, the housing has a recess formed in the inner bottom, and the light emitting element is flip-chip mounted in the recess to receive light. The element is characterized in that it is flip-chip mounted so as to straddle the recess with its light receiving surface facing downward.

  In the optically coupled semiconductor relay according to claim 2, a light transmitting space including a concave portion between the light emitting element and the light receiving element is filled with a translucent resin layer.

  In the optically coupled semiconductor relay according to the third aspect, the light shielding resin is sealed so as to include a light transmitting resin layer in the opening of the housing.

  The optically coupled semiconductor relay according to claim 4 has a structure in which a light-shielding lid is covered on the opening of the housing.

  In the optically coupled semiconductor relay according to claim 5, a conductive shield film is formed on the outer peripheral surface of the casing.

  The optically coupled semiconductor relay of the present invention has the following effects.

  In other words, a concave portion is provided inside the housing, and the light receiving element and the light emitting element are mounted vertically opposite to each other so that the dimensional accuracy is very good. Further, since both the light receiving element and the light emitting element are flip-chip mounted, the metal wire Wiring by is unnecessary.

  Since flip-chip mounting is used, each element does not require a wiring space for inputting and outputting with a wire, so that a smaller element can be used, and the relay itself can be reduced in size and thickness. Furthermore, since both the light receiving element and the light emitting element are configured to be flip-chip mounted, the mounting process can be greatly simplified. In addition, the wiring can be shortened by flip chip mounting, and the electrical characteristics can be improved.

  In addition, since the light emitting element and the light receiving element are surrounded by a casing on the side, if sealed with a light shielding resin layer or a light shielding lid, the light emitting element and the light receiving element can be protected in a state of being almost sealed in the internal space. Very low risk of damage.

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

  FIG. 1 is a schematic longitudinal sectional view of an optically coupled semiconductor relay showing an example of the present invention.

  In the semiconductor relay 1, a light emitting element 3, a light receiving element 4, and a switching element 5 are mounted on the inner side of a housing 2 that constitutes a three-dimensional circuit board 2.

  That is, the three-dimensional circuit board 2 is made of a printed board, a ceramic board, or the like, and is formed as a hollow casing 2 having an opening 2c, and has a peripheral wall 2d and a bottom 2e. Is formed with one recess 2b. The light emitting element 3 is mounted in the recess 2b (lower stage), and the light receiving element 4 is mounted on the inner bottom 2a (upper stage) facing the light emitting element 3 with the light receiving surface facing downward and straddling the recess 2b. The switching element 5 that operates in response to an electrical output from the light receiving element 4 is mounted at another location on the inner bottom 2a (upper stage).

  A predetermined wiring pattern (not shown) is formed on the inner bottom surface of the mounting inside the housing 2, and each element 3, 4, 5 is flip-chip mounted on the wiring pattern via bumps 6 such as solder. Various through holes (not shown) for electrically connecting the inner bottom 2a surface and the outer bottom 2f surface of the housing 2 are also formed.

  In addition, a translucent resin (JCR: junction coating resin) made of transparent silicone or the like is provided in the housing 2 to secure the light transmission space 9 with these three elements 3, 4 and 5 mounted. A layer 7 is formed, and the upper portion thereof is further sealed with an epoxy-based light shielding resin layer 8 such as black so as to close the opening 2c.

  FIG. 2 is a diagram showing a schematic manufacturing procedure of the semiconductor relay 1. 2A to 2E show a plan view and a cross-sectional view corresponding to each other vertically.

  The recessed part 2b provided in the housing | casing 2 is formed so that a part of inner bottom 2a may be hollowed out. In this example, the groove is formed as a concave groove connecting opposite ends, but may be formed in an isolated hole. The recess 2b is formed by overlapping a plurality of substrates, partially cutting off the bottom 2e, or the like.

  The light-emitting element 3 is flip-chip mounted so as to be accommodated in the recess 2b, and the light-receiving element 4 is flip-chip mounted above the light-receiving element 4 so as to straddle the recess 2b. The switching element 5 is flip-chip mounted on the surface (as described above, FIGS. 2A to 2C). In this state, the light emitting element 3 and the light receiving element 4 are arranged to face each other, and a light transmission space 9 is secured between them.

  Next, transparent silicone is injected into the internal space of the housing 2 on which the three elements 3, 4, and 5 are mounted in a liquefied state having a low viscosity, and the light transmission space 9 is reliably filled. Then, the switching element 5 is filled in the middle of the height, and thereafter, heat, ultraviolet rays, etc. are applied and cured to the extent that it has a shape-retaining property to form the translucent resin layer 7 (see FIG. 2D). ).

  Then, an epoxy-based light shielding resin is sealed in the upper space to seal the space including the light receiving element 4 and the switching element 5 with the top surface exposed, and close the opening 2c of the housing 2 (above). FIG. 2 (e)). In this way, two layers of the light transmitting resin layer 7 and the light shielding resin layer 8 are formed.

  As described above, since the light emitting element 3 and the light receiving element 4 are mounted on the substrate in the internal space of the housing 2, the dimensional accuracy of the light transmission space 9 is improved. Can also contribute to downsizing.

  Further, by performing flip chip mounting, it is not necessary to use a metal wire for wiring in the internal space of the housing 2, and the manufacturing process can be shortened. In addition, the wiring can be shortened by flip chip mounting, and the electrical characteristics can be improved. Furthermore, since no metal wire is used, wire breakage due to expansion and contraction of the transparent silicone due to heat cycle or the like does not naturally occur.

  Further, since the light emitting element 3, the light receiving element 4, and the switching element 5 are surrounded on all sides by the peripheral wall 2d of the casing 2, if the light shielding resin is sealed to close the opening 2c, The inner space can be protected in an almost sealed state, and the risk of deformation or damage is extremely low.

  FIG. 3 is a diagram showing another example of the optically coupled semiconductor relay using the casing used in the above example. A plan view is omitted.

  3 (a) and 3 (b) show the case where the opening 2c is covered with a light shielding lid 10 capable of closing the opening 2c instead of the light shielding resin. In FIG. 3 (a), the transparent resin made of transparent silicone is used. The layer 7 is filled and formed. In (b), the translucent resin layer 7 is not formed.

  Thus, in the case where the light-shielding lid 10 is provided, the light-transmitting resin layer 7 made of transparent silicone may be formed so as not to enter the light transmission space such as dust, dust, and the optical coupling accuracy may be improved. In order to shorten the process, the light transmission space 9 may be secured without filling with transparent silicone.

  Further, in the optically coupled semiconductor relay 1 shown in FIGS. 1 to 3, the outer peripheral surface 2 g of the housing 2 may be formed with a skin made of a conductive shield film such as a copper foil to block electromagnetic waves. Good.

  FIGS. 4A to 4C are still other examples, and these are different from the above three examples in the internal shape of the housing 2.

  That is, in these optically coupled semiconductor relays 1, as shown in the figure, a recess 2 b that accommodates the light emitting element 3 is formed by two mounting tables 11. In other words, the inner bottom 2a is formed so as to be alternately uneven. The light receiving element 3 is mounted on the two mounting bases 11 and 11 by flip chip mounting on both ends thereof, and the switching element 5 is formed in the recess 2b in which the light emitting element 4 is flip chip mounted using the central mounting base 11 as a partition. Flip chip mounted on the opposite side. That is, the light emitting element 3 is mounted on the lower stage, the light receiving element 4 is mounted on the upper stage, and the switching element 5 is mounted on the lower stage.

  The inner bottom 2a of the housing 2 having such a shape can be formed by overlapping the main substrate and the mounting tables 11 and 11, or by partially scraping the inner bottom side of the bottom 2e.

  The three examples shown in FIGS. 4 (a) to 4 (c) correspond to FIGS. 1, 3 (a), and (b), and (a) forms a translucent resin layer made of transparent silicone. Further, a light-shielding resin encapsulated, (b) a transparent resin layer formed of transparent silicone and closed with a light-shielding lid 10, (c) is a light-shielding lid 10 without being filled with transparent silicone. It is obstructed.

  4A and 4B, since the switching element 5 is mounted in the lower stage, the entire switching element 5 is included in the translucent resin layer 7.

  The three examples in FIG. 4 can be expected to have the same effect as the three examples shown in FIGS. 1, 3A, and 3B, and the switching element is mounted on a thinner bottom than the example in FIG. Therefore, the wiring pattern to the outer bottom surface 2f of the housing 2 can also be shortened, and the electrical characteristics can be further improved.

  Next, a reference invention example relating to the present invention will be described with reference to FIGS.

  In the three examples shown in FIG. 5, one recess 2 b is formed in the housing 2, the light emitting element 3 is mounted on the recess 2 b (lower stage) with the metal wire 12, and the light receiving element 4 is placed on the upper stage so as to straddle the recess 2 b. The switching element 5 is flip-chip mounted on the upper stage. FIG. 5 (a) is a transparent silicone filled and sealed with a light shielding resin, (b) is filled with transparent silicone and closed with a light shielding lid 10, and (c) is not filled with transparent silicone. The light shielding lid 10 is closed.

  Further, in the three examples shown in FIG. 6, the recess 2 b for mounting the light emitting element 3 is formed by the two mounting tables 11, 11. The light emitting element 3 is mounted with the metal wire 12 in the recess 2 b (lower stage). The light receiving element 4 is flip-chip mounted on the upper stage so as to straddle the recess 2b, and the switching element 5 is flip-chip mounted on the lower stage. FIG. 6 (a) shows a transparent silicone filled and sealed with a light-shielding resin, (b) is filled with transparent silicone and closed with a light-shielding lid 10, and (c) is not filled with transparent silicone. The light shielding lid 10 is closed.

  Similarly, these six examples can improve dimensional accuracy and electrical characteristics. Further, since the light emitting element 3, the light receiving element 4, and the switching element 5 are surrounded on the sides by the peripheral wall 2d of the housing 2, if sealed with the light shielding resin layer 8 or the light shielding lid 10, the inner space is almost completely filled. It can be protected in a sealed state and has a very low risk of deformation and damage.

  In addition, since it is the same as that of the thing of FIGS. 1-4 about the structure part other than the above in FIG. 5, FIG. 6, it attaches | subjects the same code | symbol about them, and abbreviate | omits the description.

It is a schematic longitudinal cross-sectional view of the optical coupling type semiconductor relay which shows an example of this invention. It is a figure which shows the manufacture procedure of the optical coupling type semiconductor relay. (A), (b) is a figure which shows the other example of the optical coupling type semiconductor relay of this invention. (A)-(c) is a figure which shows the further another example of the optical coupling type semiconductor relay of this invention. (A)-(c) is a figure which shows the reference invention example regarding this invention. (A)-(c) is a figure which shows the reference invention example regarding this invention. It is a longitudinal cross-sectional view which shows an example of the conventional optical coupling type semiconductor relay.

Explanation of symbols

1 Optical coupling type semiconductor relay 2 3D circuit board (housing)
2a inner bottom 2b recess 2c opening 2d peripheral wall 2e bottom 2f outer bottom 2g outer peripheral surface 3 light emitting element 4 light receiving element 5 switching element 6 bump 7 translucent resin layer 8 light shielding resin layer 9 light transmission space 10 light shielding lid 11 mounting base

Claims (5)

An optically coupled semiconductor relay in which a light emitting element, a light receiving element disposed opposite to the light emitting element, and a switching element that receives an output from the light receiving element are mounted in an inner space of a housing having an opening. ,
The casing has a recess in the inner bottom,
The light emitting element is flip-chip mounted in the recess,
The optically coupled semiconductor relay, wherein the light receiving element is flip-chip mounted so as to straddle the concave portion with the light receiving surface facing downward. In claim 1,
An optically coupled semiconductor relay, wherein a light transmitting space including the concave portion between the light emitting element and the light receiving element is filled with a translucent resin layer. In claim 2,
A light-coupled semiconductor relay, wherein a light-shielding resin is sealed in the opening of the housing so as to include the light-transmitting resin layer. In any one of Claims 1, 2,
An optically coupled semiconductor relay, wherein an opening of the housing is covered with a light shielding lid. In any one of Claims 1-4,
An optically coupled semiconductor relay, wherein the casing is formed with a conductive shield film on an outer peripheral surface.

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