JP2012199311A - Photocoupler - Google Patents

Abstract

Provided is a photocoupler which can be reduced in height and can reduce the number of parts.
A wiring board, an IR light-emitting device bonded to the surface of the wiring board, and an IR light receiving bonded to a position away from the IR light-emitting device on the surface of the wiring board. The light emitting surface 61a of the light emitting unit 61 included in the IR light emitting device 60 and the light receiving surface 20a of the optical filter 20 included in the IR light receiving device 50 face each other on the surface 1a of the wiring board 1. . Since the IR light emitting device 60 and the light receiving device 50 are not in the vertical direction but in the horizontal positional relationship, the height of the photocoupler can be reduced. Further, since the light output from the light emitting surface 61a is directly incident on the light receiving surface 20a without passing through the concave reflecting surface or the like, the concave reflecting surface or the like is unnecessary, and the number of components can be reduced. .
[Selection] Figure 1

Description

  The present invention relates to a photocoupler.

As this type of prior art, for example, there is one disclosed in Patent Document 1. In this document, as shown in FIG. 5, a photocoupler having a structure in which a light emitting surface of a light emitting element and a light receiving surface of a light receiving element are vertically opposed in a light shielding resin (hereinafter, a conventional example). 1)).
FIG. 1 of Patent Document 1 has a structure in which the light emitting surface of the light emitting element and the light receiving surface of the light receiving element are directed upward, and a concave reflecting surface is disposed above the light emitting element and the light receiving element. A photocoupler (hereinafter referred to as Conventional Example 2) is disclosed. In Conventional Example 2, the lower surface of the light-shielding resin is a concave reflecting surface, and the light emitted from the light emitting surface of the light emitting element undergoes two reflections on the concave reflecting surface and the light receiving surface of the light receiving element. To come to reach.

JP 2001-358361 A

By the way, in the above-mentioned conventional example 1, the positional relationship between the light emitting element and the light receiving element in the light shielding resin is in the vertical direction, so that there is a problem that the height of the photocoupler increases. On the other hand, in Conventional Example 2, since the light emitting element and the light receiving element are disposed on one surface of the insulating substrate, the height of the package may be reduced as compared with Conventional Example 1.
However, Conventional Example 2 has a problem that a concave reflecting surface is required to secure an optical path from the light emitting surface of the light emitting element to the light receiving surface of the light receiving element, and the number of components is increased accordingly. As described above, in the conventional examples 1 and 2, there are problems with respect to the height of the photocoupler and the number of parts, and the system tends to be large overall.
Accordingly, the present invention has been made in view of such circumstances, and an object of the present invention is to provide a photocoupler that can be reduced in height and can reduce the number of components.

  In order to solve the above problems, a photocoupler according to an aspect of the present invention includes a wiring board, a light-emitting device bonded to one surface of the wiring board, and one surface of the wiring board. A light receiving device bonded to a position away from the light emitting device, and the light emitting surface of the light emitting device and the light receiving surface of the light receiving device face each other on one surface of the wiring board. And

  With such a configuration, the height of the photocoupler can be reduced because the light emitting device and the light receiving device are not in the vertical direction but in the horizontal positional relationship as compared with the conventional example 1. Further, compared with the conventional example 2, the light output from the light emitting surface of the light emitting device is directly incident on the light receiving surface of the light receiving device without passing through the concave reflecting surface or the like. It is not necessary to arrange etc. For this reason, the number of parts can be reduced. Furthermore, the optical path does not spread due to light scattering on the concave reflecting surface. The “one surface of the wiring board” of the present invention corresponds to, for example, the surface 1a of the wiring board 1 described later.

  Further, in the above-described photocoupler, the light receiving device includes a light receiving element that detects light, a lead frame having a through portion, a wire, and a sealing portion, and the light receiving device is received in the through portion of the lead frame. An element is disposed, the photoelectric conversion part of the light receiving element and the lead frame are electrically connected by the wire, and the sealing part has a light receiving surface of the light receiving element on a surface facing the light emitting device. In addition, the side surface of the lead frame is exposed as a plurality of terminal portions electrically connected to the wiring substrate in a vertical manner on a surface to be bonded to one surface of the wiring substrate. It is good also as a feature.

  With such a configuration, the arrangement position of the light receiving element is not on the lead frame but in the through portion of the lead frame. Thereby, since the mounting position of the light receiving element can be lowered, a thinner light receiving device can be realized. This can contribute to miniaturization of the photocoupler. The “sealing portion” of the present invention corresponds to, for example, a mold resin 45 described later. As the “photoelectric conversion unit”, for example, a photoelectric conversion element 13 described later corresponds.

Further, in the above-described photocoupler, each of the plurality of terminal portions is, in plan view, one side of the joined surface and the other side on the opposite side of the one across the center of the joined surface It is good also as the characteristic that it arrange | positions so that it may become symmetrical, respectively.
With such a configuration, since a plurality of terminal portions are arranged in a balanced manner on the surfaces to be joined, even when soldering the plurality of terminal portions through, for example, a reflow furnace, the physical properties of the solder in the soldering process, etc. The resulting moment balance can be maintained. Thereby, it is possible to suppress the occurrence of so-called Manhattan phenomenon. As the “plurality of terminal portions” of the present invention, for example, a side surface (external connection terminal portion) 31c of the first lead frame 31 described later and a side surface (external connection terminal portion) of the second lead frame 36 are used. ) 36c is applicable.

  In the photocoupler, the light receiving device further includes a lid attached to the sealing portion, and an optical filter that covers a light receiving surface of the light receiving element, and an opening penetrating the lid. A portion may be provided, and the optical filter may be housed in the opening. Here, the optical filter has a function of selectively transmitting light in a desired wavelength range (that is, having high transmittance). With such a configuration, only light in a desired wavelength range can reach the light receiving surface of the light receiving element, and light outside the wavelength range can be blocked by the optical filter. For this reason, it is possible to improve the S / N ratio for an electrical signal (that is, a light detection signal) output from the light receiving element by photoelectric conversion.

  In the above-described photocoupler, the lead frame includes a first lead frame having a first penetrating portion and a second lead frame having a second penetrating portion, and the second lead frame. The first lead frame is disposed above the first penetrating portion and the second penetrating portion in plan view, and the first penetrating portion and the second penetrating portion serve as the penetrating portion. The sealing portion is molded in a state where the light receiving element is disposed in a region overlapping with the portion in plan view, and the first lead frame of the first lead frame is formed from the bonded surface of the molded sealing portion. One side surface and the second side surface of the second lead frame may be exposed as the plurality of terminal portions, respectively.

  With such a configuration, one lead frame is configured by a combination of the first lead frame and the second lead frame. Further, the width of the penetrating portion of this one lead frame (that is, the region where the first penetrating portion and the second penetrating portion overlap in plan view) is the first penetrating portion (or the second penetrating portion). ) And the depth is the sum of the depths of the first and second penetrating portions. For this reason, it is possible to easily realize a through-hole that is narrow and deep (that is, has a large aspect ratio).

  In the photocoupler, the light receiving element includes a first light receiving element and a second light receiving element, and the optical filter has characteristics different from those of the first optical filter and the first optical filter. A second optical filter, wherein the penetrating portion includes a first region and a second region having a position different from the first region, and the opening includes the first opening, A second opening having a position different from that of the first opening, wherein the first light receiving element is disposed in the first region, and the second light receiving element is disposed in the second region, The first optical filter may be housed in the first opening, and the second optical filter may be housed in the second opening. Here, examples of the “characteristic” include a light transmittance characteristic depending on the wavelength. For example, the first optical filter has a function of selectively transmitting only light in the first wavelength range (that is, high transmittance) as its characteristics. The second optical filter has a function of selectively transmitting only light in a second wavelength range different from the first wavelength range as its characteristics.

  With such a configuration, for example, the intensity of incident light and its wavelength based on the electric signal output from the first light receiving element and the electric signal output from the second light receiving element. The range can be specified. For example, in the infrared rays irradiated in a specific gas atmosphere, a specific wavelength component is quantitatively absorbed according to the gas type and its concentration. For this reason, by specifying the intensity of light irradiated from the light emitting device and entering the light receiving device and its wavelength range, it is possible to detect the type of gas present in the optical path and its concentration. Therefore, it can be used very suitably for a gas detector or the like.

  In the above-described photocoupler, the light receiving device includes a light receiving element that detects light, an optical filter that covers a light receiving surface of the light receiving element, a first lead frame having a first penetrating portion, and a second lead frame. A second lead frame having a penetrating portion; a wire and a sealing portion; wherein the first lead frame is disposed on the second lead frame; The light receiving element and the optical filter are disposed in a region where the two through parts overlap in plan view, and the first through part and the second through part overlap in plan view. The sealing part is molded in a state where the photoelectric conversion part provided on the surface opposite to the light receiving surface and the lead frame are electrically connected by the wire, and the outside of the molded sealing part The surface exposed to The light receiving surface of the optical filter is exposed from the surface facing the optical device, and is further exposed to the outside of the molded sealing portion, and is one surface of the wiring board As a plurality of terminal portions to which the first side surface of the first lead frame and the second side surface of the second lead frame are electrically connected to the wiring board from the joined surfaces to be joined together Each may be characterized by being exposed.

  With such a configuration, the combination of the first lead frame and the second lead frame makes it possible to easily realize a through portion having a narrow width and a deep width (that is, a large aspect ratio). Thereby, it becomes easy to secure a space for storing the optical filter in the through portion of the lead frame. Since the mounting position of the light receiving element and the optical filter can be lowered, a thinner light receiving device can be realized.

  In the photocoupler, the light receiving element includes a first light receiving element and a second light receiving element, and the optical filter includes a first optical filter that covers a light receiving surface of the first light receiving element, and A second optical filter having characteristics different from those of the first optical filter and covering a light receiving surface of the second light receiving element, wherein the first penetrating portion and the second penetrating portion are in plan view. The overlapping region includes a first region and a second region having a position different from that of the first region, and the first light receiving element and the first optical filter are disposed in the first region, The second light receiving element and the second optical filter may be arranged in the second region. With such a configuration, for example, the intensity of incident light is changed for each wavelength range based on the electric signal output from the first light receiving element and the electric signal output from the second light receiving element. It becomes possible to specify. Therefore, for example, it can be used very suitably for a gas detector or the like.

  According to the present invention, it is possible to provide a photocoupler that can be reduced in height and can reduce the number of components.

1 is a diagram illustrating a configuration example of a photocoupler 100 according to a first embodiment. The figure which shows the structural example of IR light receiving apparatus 50 which concerns on 1st Embodiment. FIG. 3 is a diagram illustrating a configuration example of a light receiving element 10. FIG. 3 is a diagram illustrating a configuration example of a first lead frame 31 according to the first embodiment. FIG. 3 is a diagram illustrating a configuration example of a second lead frame 36 according to the first embodiment. The figure which shows the structural example of the cover body. The figure which shows the manufacturing method of the photocoupler. The figure which shows the manufacturing method of the photocoupler. The figure which shows the manufacturing method of the photocoupler. The figure which shows the manufacturing method of the photocoupler. The figure which shows the manufacturing method of the photocoupler. The figure which shows the manufacturing method of the photocoupler. The figure which shows the structural example of the photocoupler 200 which concerns on 2nd Embodiment. The figure which shows the manufacturing method of the photocoupler. The figure which shows the structural example of the photocoupler 300 which concerns on 3rd Embodiment. The figure which shows the structural example of the lead frame 130 which concerns on 3rd Embodiment. FIG. 5 is a view showing a method for manufacturing the photocoupler 300. The figure which shows the other structural example of IR light-receiving device 50. FIG. FIG. 6 is a diagram showing another configuration example of the first lead frame 31 and the second lead frame 36. FIG. 10 is a diagram illustrating another configuration example of the photocoupler 100.

Hereinafter, embodiments according to the present invention will be described with reference to the drawings. Note that, in each drawing described below, parts having the same configuration are denoted by the same reference numerals, and repeated description thereof may be omitted.
(1) First Embodiment (1.1) Overall Configuration of Photocoupler FIGS. 1A and 1B show a surface-facing surface mount type and vertical mount type photo according to a first embodiment of the present invention. It is the perspective view which shows the structural example of the coupler 100, and sectional drawing which cut | disconnected this perspective view by the Z1-Z'1 line | wire. In addition, illustration of a housing | casing is abbreviate | omitted in FIG.1 (b).

  As shown in FIGS. 1A and 1B, the photocoupler 100 includes, for example, a wiring board 1, an IR light emitting device 60 bonded on the surface 1 a of the wiring board 1, and the surface of the wiring board 1. An IR light receiving device 50 that is bonded to a position apart from the IR light emitting device 60 on 1a, and a casing 90 that surrounds the wiring substrate 1, the IR light emitting device 60, and the IR light receiving device 50 from the outside.

  Here, the IR light emitting device 60 emits infrared light (IR), and is, for example, an IR light emitting diode or a light bulb (that is, light emitting only infrared light, or light including infrared light and other wavelengths). May emit light.). The IR light receiving device 50 is a sensor device that receives IR, for example, and converts the received IR into an electrical signal and outputs the converted electrical signal. In this photocoupler 100, on the surface 1 a of the wiring substrate 1, the light emitting surface 61 a of the light emitting unit 61 of the IR light emitting device 60 and the light receiving surface of the IR light receiving device 50 (in this example, the optical housed in the lid 55. The light receiving surface 20a) of the filter 20 is opposed. That is, the photocoupler 100 is a surface-facing surface-mounting type in which the light-emitting surface 61a and the light-receiving surface 20a are mounted on the surface 1a in a state of facing each other. Thereby, the light output from the light emitting surface 61 a of the IR light emitting device 60 is directly incident on the light receiving surface 20 a of the optical filter 20.

The housing 90 is made of, for example, a light-shielding resin, and a gas inflow opening 91 is provided in a part thereof. By being surrounded by the light shielding case 90, only the light output from the light emitting surface 61a of the IR light emitting device 60 reaches the light receiving surface 20a of the optical filter 20, and other light (that is, the outside of the case). (Light from) is not reached.
In this photocoupler 100, the dimension of the IR light receiving device 50 in the Z direction (that is, the thickness direction, which is also the direction along the optical path) is L1, and the IR light receiving device 50 is dimensioned in the Y direction (that is, the height direction). When the length is H1, L1 <H1, and it is a vertical mounting type.

  In other words, the vertical mounting type means that the outer shape (package) is a rectangular parallelepiped, and the first surface having the largest area among the six surfaces of the rectangular parallelepiped is orthogonal to the surface of the wiring board, and the rectangular parallelepiped One of the six surfaces is a form in which a second surface having a smaller area than the first surface is bonded to the surface of the wiring board. In the embodiment of the present invention, the “second surface” is a bonded surface 49 (see, for example, FIG. 2C) described later, and the side surface 31 c of the lead frame 31 is exposed from the bonded surface 49. ing. The exposed side surface 31c is electrically connected to the wiring board 1 as a plurality of terminal portions (ie, vertical mounting connection). Thereby, on the surface 1a of the wiring board 1, the mounting area (footprint) of the IR light receiving device 50 is reduced.

  In this example, the lid body 55 also functions as a support member for the IR light receiving device 50 mounted in the vertical direction. Further, the lid body 55 may be fixed to the surface 1a of the wiring board 1 with an adhesive or the like (not shown). In this case, the support function can be further strengthened. Next, each part which comprises the photocoupler 100 is demonstrated concretely.

(1.2) Configuration of IR Light-Receiving Device As shown in FIGS. 1A and 1B, the IR light-receiving device 50 includes, for example, a light-receiving element 10 that detects infrared rays (IR), a lead frame 30, and light reception. A wire 40 made of gold (Au) or the like for electrically connecting the element 10 and the lead frame 30 and a mold resin 45 covering the light receiving element 10 are provided. Further, the IR light receiving device 50 includes, for example, a lid 55 attached (fixed) to the mold resin 45 by an adhesive 46, an optical filter 20 housed in an opening through which the lid 55 passes, Is provided.

2A to 2C are a perspective view showing an example of an external appearance of the IR light receiving device 50 according to the first embodiment of the present invention with the lid removed, and this perspective view is shown as Z2-Z'2. It is sectional drawing cut | disconnected by the line | wire, and a top view which shows the to-be-joined surface 49 of IR light receiving device 50. FIG.
As shown in FIG. 2A, the package of the IR light receiving device 50 (that is, mold resin) is, for example, a rectangular parallelepiped. As shown in FIG. 2B, the IR light receiving device 50 includes, for example, two light receiving elements 10. The light receiving surface 16b of each of the two light receiving elements 10 is disposed so as to be flush with the upper surface of the package (that is, the back surface 36b side of the second lead frame 36). Further, in the IR light receiving device 50, the lead frame 30 includes a first lead frame 31 and a second lead frame 36, which are overlapped to form one lead frame 30.

  In the IR light receiving device 50, one of the four side surfaces is a surface to be bonded to the surface 1 a of the wiring substrate 1. Specifically, as shown in FIGS. 2A and 2C, side surfaces of the IR light receiving device 50, that is, a side surface 31 c of the first lead frame 31 and a side surface 36 c of the second lead frame 36. The exposed surface is the bonded surface 49. The side surface 31c of the first lead frame 31 exposed at the surface to be bonded 49 and the side surface 36c of the second lead frame 36 are bonded onto the surface 1a of the wiring board 1 through the solder 3, for example. This is a portion that functions as an external connection terminal portion of the IR light receiving device 50.

  By the way, in this IR light receiving device 50, each of the plurality of external connection terminal portions 31c and 36c has one side of the bonded surface 49 and one opposite side across the center of the bonded surface 49 in plan view. It arrange | positions so that it may become symmetrical with the other side in each. Specifically, as shown in FIG. 2 (c), the shape and size of the first external connection terminal portion 31c and the arrangement thereof, and the shape and size of the second external connection terminal portion 36c and the arrangement thereof. The arrangement is arranged symmetrically about the center line (virtual line) L of the bonded surface 49. As described above, each of the plurality of external connection terminal portions 31 c and 36 c is arranged in a well-balanced manner on the bonded surface 49. Thereby, the balance of the moment resulting from the physical property etc. of a solder can be maintained in the soldering process mentioned later, and generation | occurrence | production of what is called a Manhattan phenomenon can be suppressed.

(1.2.1) Configuration of Light Receiving Element FIGS. 3A and 3B are diagrams showing a configuration example of the light receiving element 10, and FIG. 3A is a diagram showing the surface 16 a side of the light receiving element 10. FIG. 3B is a view showing a cross section of the photoelectric conversion element 13. A light receiving element 10 shown in FIG. 3A is, for example, a sensor element that detects infrared rays (IR), and a light transmitting substrate 11 that transmits IR, and a light receiving unit formed on the surface 16a side of the light transmitting substrate 11. 12.

  Among these, a GaAs substrate is used as the light transmission substrate 11. In addition to the GaAs substrate, for example, a semiconductor substrate such as Si, InAs, InP, GaP, or Ge, or a substrate such as GaN, AlN, sapphire substrate, or glass substrate is used. According to such a board | substrate, the light of specific wavelengths, such as infrared rays, can be permeate | transmitted efficiently from the back surface 16b of the light transmissive board | substrate 11 to the surface 16a. In addition, the light receiving unit 12 includes a plurality of photoelectric conversion elements 13, a pad unit 14 for outputting an electrical signal photoelectrically converted by the photoelectric conversion element 13, and a wiring 15. Each of the photoelectric conversion elements 13 is a quantum photodiode, and is connected in series by a wiring 15. As the number of connected photoelectric conversion elements 13 increases, the generated electromotive force increases, and the sensitivity as a sensor increases.

  As shown in FIG. 3B, the photoelectric conversion element 13 includes, for example, an n-type compound semiconductor layer (n layer) such as InSb containing indium (ln) and antimony (Sb) formed on the light transmission substrate 11. ) 13a, a non-doped compound semiconductor layer (π layer) 13b formed on the n layer 13a, and AlInSb formed on the π layer 13b and having a band gap larger than that of the n layer 13a and the π layer 13b. And a p-type compound semiconductor layer (p layer) 13d formed on the compound semiconductor layer 13c and doped with p-type impurities at a high concentration. Thus, the photoelectric conversion element 13 in which the n layer 13a, the π layer 13b, the compound semiconductor layer 13c having a larger band gap than the n layer 13a and the π layer 13b, and the p layer 13d are sequentially stacked has a thickness of 2000 nm. Infrared light of ˜7400 nm can be detected.

  The pad portion 14 shown in FIG. 3A is provided for outputting an electrical signal obtained by photoelectric conversion of the light receiving portion 12. The pad portion 14 includes, for example, a pair of pad electrodes 14a and 14b that are disposed apart from each other. The wiring 15 is electrically connected between one pad electrode 14a and one end of the row of the plurality of photoelectric conversion elements 13, and between the other pad electrode 14b and the other end of the row. .

  By the way, in this light receiving element 10, the pad portion 14 is arranged in a partial range (center part) closer to the center of the surface of the light receiving element 10. A plurality of photoelectric conversion elements 13 are arranged around the pad portion 14. According to such an arrangement, there is an advantage that the light transmitting substrate 11 is not easily lost even when pressure or ultrasonic waves are applied when wire bonding is performed to the pad electrodes 14a and 14b. Further, since the light transmission substrate 11 is not easily damaged, a wire made of Au or the like can be bonded to the pad electrodes 14a and 14b with sufficient pressure or ultrasonic waves. For this reason, a wire can be reliably crimped | bonded by pad electrode 14a, 14b, and the reliability of wire bonding can be improved.

(1.2.2) Configuration of Lead Frame FIGS. 4A and 4B are plan views showing a configuration example of the first lead frame 31 according to the first embodiment of the present invention. FIG. 4A shows the front surface 31 a of the first lead frame 31, and FIG. 4B shows the back surface 31 b of the first lead frame 31. In the first lead frame 31 shown in FIGS. 4A and 4B, for example, a copper (Cu) plate is selectively etched from the front surface 31a side and the back surface 31b side by a photolithography technique. (Ni) -palladium (Pd) -gold (Au) or other plating (plating) treatment is performed.

  In FIG. 4A, the white region in the first lead frame 31 shows the first through portion 32 that penetrates between the front surface 31a and the back surface 31b, and the hatched region is from the front surface 31a side. A half-etched region (that is, a half-etched region) 33a is shown. A gray region indicates a region (that is, a non-etched region) 34a that is not etched by masking the surface 31a with a photoresist or the like during etching.

  Similarly, in FIG. 4B, the white region in the first lead frame 31 indicates the first through portion 32, and the hatched region is a half-etched region 33b half-etched from the back surface 31b side. Indicates. A gray region indicates a non-etched region 34b that was not etched by masking the back surface 31b with a photoresist or the like during etching. The outer periphery of the first lead frame 31 shown in FIGS. 4A and 4B is a region (referred to as a kerf width) 35 that is cut by a dicing blade or the like in a dicing process described later.

  FIGS. 5A and 5B are plan views showing a configuration example of the second lead frame 36 according to the first embodiment of the present invention. FIG. 5A shows the front surface 36 a of the second lead frame 36, and FIG. 5B shows the back surface 36 b of the second lead frame 36. Like the first lead frame 31 shown in FIGS. 4A and 4B, the second lead frame 36 shown in FIGS. 5A and 5B is made of, for example, a Cu plate by photolithography technology. Thus, the surface 36a and the back surface 36b are selectively etched from each side and plated with Ni—Pd—Au or the like.

  In FIG. 5A, the white area in the second lead frame 36 indicates the second through portion 37 that penetrates between the front surface 36a and the back surface 36b, and the hatched area is from the front surface 36a side. A half-etched region 38a that has been half-etched is shown. A gray region indicates a non-etched region 39a that has not been etched by masking the surface 36a with a photoresist or the like during etching.

  Similarly, in FIG. 5B, the white area in the second lead frame 36 indicates the second through portion 37, and the hatched area is half-etched from the back surface 36b side. 38b is shown. A gray region indicates a non-etched region 39b that was not etched because the back surface 36b was masked with a photoresist or the like during etching. The outer periphery of the second lead frame 36 shown in FIGS. 5A and 5B has a kerf width 35 that is cut by a dicing blade or the like in a dicing process described later.

  As can be seen by comparing FIGS. 4A and 4B and FIGS. 5A and 5B, the first lead portion 32 of the first lead frame 31 and the second lead frame 36 The second penetrating portions 37 are formed so that the shapes in plan view (that is, the planar shape) are the same, and the lengths in plan view (ie, the length in the vertical and horizontal directions) are also the same. Therefore, when the first lead frame 31 and the second lead frame 36 are overlapped, the two through portions 32 and 37 are overlapped to form one continuous through portion 51 (for example, FIG. (B)) is configured.

  The shape and size (that is, vertical and horizontal dimensions) of the penetrating portion 51 in plan view are the same as those of the first and second penetrating portions 32 and 37, respectively. Further, the depth of the penetrating portion 51 is the sum of the depths of the first and second penetrating portions 32 and 37. That is, the combination of the first lead frame 31 and the second lead frame 36 forms a through-hole 51 that is narrow and deep (ie, has a large aspect ratio).

(1.2.3) Configuration of Lid FIGS. 6A and 6B are a plan view showing a configuration example of the lid 55 according to the first embodiment of the present invention, and this plan view is represented by Y6-Y. It is sectional drawing cut | disconnected by '6 line.
As shown in FIGS. 6A and 6B, the lid 55 has, for example, the same shape as that of the IR light receiving device 50 in a plan view and the same size (actually, the lid for the package). In order to facilitate the attachment of 55, the plate portion 56 having a size slightly larger than the package) and a guide portion 59 provided on the outer periphery of the plate portion 56 are provided. A penetrating opening 57 is provided in a portion of the plate portion 56 corresponding to the light receiving element (that is, a portion facing the light receiving surface of the light receiving element when the lid 55 is attached to the package).

  In this example, since two light receiving elements are prepared as described above, two corresponding openings 57 are also prepared. That is, as shown in FIG. 6A, the first opening 57 and the second opening 57. Each of these two openings 57 has a recess 58 for accommodating the optical filter. The lid 55 is, for example, a liquid crystal polymer used in injection molding and is made of a material having a thermal deformation temperature of 250 ° C. or higher. Thereby, it can endure the reflow conditions (for example, furnace temperature 260 degreeC, time 10 second) at the time of mounting.

  As shown in FIG. 1A, when the lid 55 is placed on the package, the guide portion 59 covers three side surfaces of the package except for the bonded surface 49. Thereby, it is possible to prevent light from leaking from the three side surfaces of the package to the light receiving surface side of the light receiving element 10. Further, since the mounting position of the lid body 55 with respect to the package is determined by the guide portion 59, the lid body 55 can be easily attached.

(1.2.4) Configuration of Optical Filter The optical filter 20 shown in FIGS. 1A and 1B has a function of selectively transmitting light in a desired wavelength range (that is, having high transmittance). Is. For example, the optical filter 20 has a function of transmitting only infrared rays.
Alternatively, the optical filter 20 may have a function of transmitting only infrared rays in a specific wavelength range among infrared rays. For example, the optical filter 20 has an optical member and a thin film formed in a multilayer on the optical member, and has a function of not transmitting infrared rays having a long wavelength, a short wavelength, or both, and these It may have a function of transmitting only infrared rays having a specific wavelength as a result of combining the transmission functions.

The optical filter 20 may perform a function of transmitting only infrared rays having a specific wavelength, or may use a plurality of sheets depending on circumstances. In addition, as a material of the optical member, a material that transmits predetermined infrared rays such as silicon (Si), glass (SiO ₂ ), sapphire (Al ₂ O ₃ ), Ge, ZnS, ZnSe, CaF ₂ , and BaF ₂ is used. The thin film materials used and deposited on this include silicon (Si), glass (SiO ₂ ), sapphire (Al ₂ O ₃ ), Ge, ZnS, TiO ₂ , MgF ₂ , SiO ₂ , ZrO ₂ , Ta ₂ O ₅ or the like is used. In addition, the dielectric multilayer filter in which dielectrics having different refractive indexes are laminated in layers on the optical member may be formed on both sides with a predetermined thickness configuration different on the front and back sides, or formed only on one side. May be. Further, for the purpose of preventing unnecessary reflection, an antireflection film may be formed on the front surface, both surfaces on the back surface, or the outermost layer on one surface.

  In this example, as shown in FIGS. 1A and 1B, two optical filters 20 are provided corresponding to the number of light receiving elements 10. Here, one of the two optical filters 20 (that is, the first optical filter) and the other (that is, the second optical filter) have different optical characteristics. For example, the first optical filter 20 selectively transmits infrared rays in a first wavelength range (long wavelength), and the second optical filter 20 selects infrared rays in a second wavelength range (short wavelength). Is transparent. Thereby, for example, an electric signal output from the first light receiving element 10 covered with the first optical filter 20 and an electric signal output from the second light receiving element 10 covered with the second optical filter 20 Based on the above, it is possible to specify the intensity of incident light and its wavelength range.

  According to the photocoupler 100 having the above configuration, since the positional relationship between the IR light emitting device 60 and the IR light receiving device 50 is in the horizontal direction, the height of the entire system can be reduced. The light output from the light emitting surface 61 a of the IR light emitting device 60 is directly incident on the light receiving surface 20 a of the optical filter 20. Since a concave reflecting surface that changes the traveling direction of light is not required between the IR light emitting device 60 and the IR light receiving device 50, the number of components can be reduced.

  Furthermore, according to this photocoupler 100, by specifying the intensity of IR that is irradiated from the IR light emitting device 60 and incident on the IR light receiving device 50, and its wavelength range, Its concentration can be detected. This is because IR irradiated in a specific gas atmosphere absorbs a specific wavelength component quantitatively according to the gas type and its concentration. Therefore, the above-described photocoupler 100 can be used very suitably for a gas detector or the like. Next, a method for manufacturing the photocoupler 100 according to the first embodiment will be described.

(1.3) Photocoupler Manufacturing Method FIGS. 7 to 12B are process diagrams showing a method of manufacturing the photocoupler 100 according to the first embodiment of the present invention. FIG. 7 is a perspective view. 8A to 12A are plan views viewed from the front surface side of the lead frame 30 (more specifically, from the front surface 31a side of the first lead frame 31). (B) is sectional drawing when (a) is each cut | disconnected by X8-X'8-X12-X'12 line | wire.

  As shown in FIG. 7, first, a first lead frame 31 'and a second lead frame 36' are prepared. Here, the first lead frame 31 shown in FIGS. 4A and 4B is used as one unit pattern, and the unit patterns are arranged so as to be continuously arranged in the vertical direction and the horizontal direction in plan view. A lead frame 31 'is prepared. Similarly, the second lead frame 36 shown in FIGS. 5A and 5B is used as one unit pattern, and the unit patterns are arranged so as to be continuously arranged in the vertical direction and the horizontal direction in plan view. A lead frame 36 'is prepared.

Next, the adhesive tape 71 is affixed to the back surface 36b of the second lead frame 36 '. By sticking the adhesive tape 71 to the back surface 36b side of the second lead frame 36 ', the adhesive tape 71 is adhered to the bottom surface of the second penetrating portion 37 (see, for example, FIGS. 5A and 5B). The layer is exposed.
As the adhesive tape 71, a resin tape having adhesiveness and heat resistance is used. About adhesiveness, the one where the paste thickness of the adhesion layer is thinner is preferable. Moreover, about heat resistance, it is required to endure the temperature of about 150 to 200 degreeC. As such an adhesive tape 71, for example, a polyimide tape can be used. The polyimide tape has heat resistance that can withstand about 280 ° C. Such a polyimide tape having high heat resistance can withstand high heat applied during subsequent molding or wire bonding. In addition to the polyimide tape, the following tape can also be used as the adhesive tape 71.

-Polyester tape Heat-resistant temperature, about 130 ° C (however, the heat-resistant temperature reaches about 200 ° C depending on use conditions).
・ Teflon (registered trademark) tape Heat-resistant temperature: about 180 ℃
・ PPS (polyphenylene sulfide) Heat-resistant temperature: about 160 ℃
・ Glass cloth heat resistant temperature: about 200 ℃
・ Nomek Paper Heat-resistant temperature: about 150-200 ℃
In addition, aramid and crepe paper can be used as the adhesive tape 71.

  Next, the first lead frame 31 ′ is disposed on the surface 36 a of the second lead frame 36 ′. Here, the front surface 36a of the second lead frame 36 'and the back surface 31b of the first lead frame 31' face each other, and in this state, refer to the first through portion 32 (see FIGS. 4A and 4B). ) Align the first lead frame 31 ′ and the second lead frame 36 ′ so that the second lead frame 37 (see FIGS. 5A and 5B) is directly above. Then, the first lead frame 31 ′ is arranged and fixed on the surface 36 a of the second lead frame 36 ′ in the aligned state. Thereby, as shown in FIGS. 8A and 8B, a lead frame 30 ′ is formed.

  Here, it is not necessary to bond the first lead frame 31 ′ and the second lead frame 36 ′ with an adhesive or the like. It is sufficient to temporarily fix the first lead frame 31 ′ and the second lead frame 36 ′ so that they are not relatively displaced. The reason is that the first lead frame 31 ′ and the second lead frame 36 ′ are fixed by the mold resin 45 in the resin sealing step described later. As a temporary fixing method, for example, there are the following methods.

  That is, as shown in FIG. 7, through holes 73 and 74 are provided in the outer periphery of the first lead frame 31 ′ and the outer periphery of the second lead frame 36 ′, respectively. By aligning the first lead frame 31 ′ and the second lead frame 36 ′, the through holes 73 and 74 overlap with each other in plan view. Two or more such through holes 73 and 74 are provided in each of the first lead frame 31 ′ and the second lead frame 36 ′. Here, the first lead frame 31 ′ and the second lead frame 36 ′ are connected by fitting the pins 75 into the through holes 73 and 74 that overlap each other at a plurality of locations (for example, two locations). It can be temporarily fixed so as not to be displaced. Further, after the alignment, the four corners may be arc-welded, or only the four corners may be bonded with an adhesive.

  Next, as shown in FIGS. 9A and 9B, for example, two light receiving elements 10 are respectively disposed in the through portions 51 of the lead frame 30 ′. Here, the 1st light receiving element 10 is arrange | positioned in the 1st area | region of the penetration part 51, The light-receiving surface 16b is affixed on the adhesion layer of the adhesive tape 71 used as the bottom face of the penetration part 51. FIG. Further, the second light receiving element 10 is disposed in the second region of the penetrating portion 51, and the light receiving surface 16 b is attached to the adhesive layer of the adhesive tape 71 serving as the bottom surface of the penetrating portion 51.

Note that a protective film (not shown) may be formed in advance on the light receiving surface 16b of the light receiving element 10 at the time of sticking. As the protective film, for example, a photoresist can be used. Such a protective film can be formed, for example, before dicing a GaAs substrate that is a base material of the light receiving element 10.
Next, as shown in FIGS. 10A and 10B, the light receiving element 10 and the lead frame 30 ′ are electrically connected using a wire 40. Here, at least a part of the half-etched region 33a of the lead frame 30 ′ becomes a bonding terminal portion. The bonding terminal portion 33a is electrically connected to the pad electrodes 14a and 14b of the light receiving element 10 shown in FIG. 3A by using a wire 40 made of Au or the like.

  The light receiving element 10 and the lead frame 30 ′ are connected by extending a wire from the bonding terminal portion 33 a of the lead frame 30 ′ toward the pad electrodes 14 a and 14 b of the light receiving element 10 (that is, viewed from the light receiving element 10). And reverse bonding). That is, first, stud bumps (not shown) are formed on the pad electrodes 14 a and 14 b of the light receiving element 10 before performing the first bond accompanied by the formation of the ball. Next, the 1st bond accompanied with the formation of the ball is performed on the bonding terminal portion 33a of the lead frame 30 ', and the 2nd bond is performed on the stud bumps of the pad electrodes 14a and 14b of the light receiving element 10. With such a method, since the bonding terminal portion 33a of the lead frame 30 'is lower in the sectional view than the pad electrodes 14a and 14b of the light receiving element 10, the height of the wire after bonding is lowered. can do.

  Next, as shown in FIGS. 11A and 11B, the upper mold 77 is disposed on the upper surface side of the lead frame 30 ′, and the lower mold 78 is disposed on the lower surface side of the lead frame 30 ′. Then, the lead frame 30 ′ is sandwiched between the upper mold 77 and the lower mold 78, and the mold resin 45 is injected from the side into the space between the upper mold 77 and the lower mold 78 and filled. Thereby, the light receiving element 10 and the wire 40 are resin-sealed.

  As the mold resin 45, for example, an epoxy resin can be used. In this resin sealing step, the upper mold 77 and the non-etched region 34a on the upper surface side of the first lead frame 31 ′ are in contact with each other without any gap, and the lower mold 78 and the adhesive tape 71 are not spaced from each other. With no contact, the mold resin 45 is supplied from the side of the space formed by the overlapping of both molds. For this reason, after resin sealing, the non-etched region 34a of the lead frame 30 'and the adhesive tape 71 are exposed from the mold resin 45, respectively.

  Next, the adhesive tape 71 is removed from the lower surface side of the lead frame 30 '. After removing the adhesive tape 71, post-cure and wet blasting are performed as necessary. Further, when a protective film (not shown) is formed on the light receiving surface 16b of the light receiving element 10, the protective film is removed. Then, the mold resin 45 and the lead frame 30 ′ are diced by a dicing device, and the kerf width 35 is cut. As a result, as shown in FIGS. 12A and 12B, the mold resin 45 and the lead frame 30 ′ are separated into individual products and packaged. Thereafter, a lid containing the optical filter is attached to each of the packages using an adhesive. Thereby, the light receiving surface of the light receiving element is covered with the optical filter, and the IR light receiving device 50 shown in FIG. 2 is completed.

  Next, the IR light receiving device 50 and the IR light emitting device 60 manufactured as described above are mounted on the surface 1 a of the wiring board 1. This mounting process is performed by, for example, reflow soldering. For example, a solder paste is printed on the surface 1a of the wiring board 1 in a region where the IR light receiving device 50 is to be mounted. Similarly, a solder paste is printed also on a region where the IR light emitting device 60 is to be mounted. Next, the IR light-receiving device 50 and the IR light-emitting device 60 are respectively arranged on the surface 1a of the wiring board 1 and in each predetermined area where the solder paste is printed. Then, in a state where the IR light receiving device 50 and the IR light emitting device 60 are respectively arranged, heat is applied to the wiring board 1 to melt the solder. Thereby, the IR light receiving device 50 and the IR light emitting device 60 are mounted on the surface 1a of the wiring board 1 via the solder. Through these steps, the photocoupler 100 shown in FIGS. 1A and 1B is completed.

  As described above, according to the first embodiment of the present invention, the positional relationship between the IR light-emitting device 60 and the IR light-receiving device 50 is not in the vertical direction but in the horizontal direction, so the overall system height is reduced. be able to. Further, since the IR light receiving device 50 and the IR light emitting device 60 are mounted on the surface 1a of the common wiring board 1, the IR light receiving device 50 and the IR light emitting device 60 can be easily aligned.

  Further, the light output from the light emitting surface 61 a of the IR light emitting device 60 is directly incident on the light receiving surface of the optical filter 20. Since a concave reflecting surface that changes the traveling direction of light is not required between the IR light emitting device 60 and the IR light receiving device 50, the number of components can be reduced. Furthermore, since a concave reflecting surface is unnecessary, light is not scattered on this reflecting surface. Therefore, the light path from the light emitting surface to the light receiving surface does not spread due to light scattering on the reflecting surface.

  Further, as shown in FIG. 2C, on the bonded surface 49 of the photocoupler 100, the plurality of external connection terminal portions 31c and 36c are arranged in a balanced manner on the left and right in a plan view. Thereby, in the soldering process for mounting the IR light receiving device 50 on the surface 1a of the wiring board 1, a balance of moments due to the physical properties of the solder can be maintained, and so-called Manhattan phenomenon is suppressed. be able to.

(2) Second Embodiment In the first embodiment described above, for example, as shown in FIG. 6B, the IR light receiving device 50 includes a lid 55, and the opening 55 penetrates the lid 55. The case where the optical filter is accommodated has been described. However, in the present invention, the IR light receiving device 50 does not necessarily need to include the lid 55. Further, the optical filter is not necessarily stored in the lid 55.

  FIGS. 13A and 13B are a perspective view showing a configuration example of a surface-facing surface-mount type and vertical-mount type photocoupler 200 according to the second embodiment of the present invention, and FIG. It is sectional drawing cut | disconnected by Z'13 line. As shown in FIGS. 13A and 13B, the photocoupler 200 includes a wiring board 1, an IR light emitting device 60 bonded to the surface 1 a of the wiring board 1, and the surface 1 a of the wiring board 1. In addition, an IR light receiving device 150 bonded to a position away from the IR light emitting device 60 and a light shielding housing (not shown) (see, for example, FIG. 1A) are provided. Here, the IR light receiving device 150 is, for example, a sensor device, similar to the IR light receiving device 50 described in the first embodiment, and converts the received IR into an electric signal and outputs the converted electric signal.

  This photocoupler 200 is different from the photocoupler 100 described in the first embodiment in the structure of the IR light receiving device. That is, as shown in FIGS. 13A and 13B, the IR light receiving device 150 is not attached with a lid. The optical filter 20 is attached (stacked) to the light receiving surface 16 b so as to cover the light receiving surface 16 b of the light receiving element 10, and is covered with the mold resin 45 together with the light receiving element 10. Further, the light receiving surface 20 a of the optical filter 20 is exposed from the mold resin 45 and is flush with the back surface 36 b of the second lead frame 36 (ie, flush).

In this photocoupler 200, on the surface 1a of the wiring substrate 1, the light emitting surface 61a of the light emitting unit 61 of the IR light emitting device 60 and the light receiving surface of the IR light receiving device 150 (in this example, the mold resin 45 of the optical filter 20). The light receiving surface 20a) exposed from the surface.
Even in such a configuration, as in the first embodiment, the positional relationship between the IR light-emitting device 60 and the IR light-receiving device 150 is in the horizontal direction, so that the height of the entire system can be reduced. . Further, the light output from the light emitting surface 61 a of the IR light emitting device 60 is directly incident on the light receiving surface of the optical filter 20. The photocoupler 200 is a surface-facing surface mount type, and does not require a concave reflecting surface that changes the traveling direction of light between the IR light-emitting device 60 and the IR light-receiving device 50, and further does not require a lid. . For this reason, the number of parts constituting the photocoupler can be further reduced.

Also in the second embodiment, the IR light receiving device 150 is a vertically mounted type in which the size relationship between the dimension length L2 in the thickness direction and the dimension length H2 in the height direction is L2 <H2. ing. This reduces the mounting area. Next, a method for manufacturing the photocoupler 200 according to the second embodiment will be described.
14A to 14E are cross-sectional views showing a method for manufacturing a photocoupler 200 according to the second embodiment of the present invention. In the second embodiment, the process up to the construction of one lead frame 30 'by superposing the first lead frame 31' and the second lead frame 36 'is the same as that of the first embodiment. As shown in FIG. 14A, after the lead frame 30 ′ is configured, as shown in FIG. 14B, the light receiving element 10 and the optical filter 20 are stacked in the penetrating portion 51 of the lead frame 30 ′. Place the body.

  Here, the light receiving surface 20 a of the optical filter 20 is affixed to a region having the adhesiveness of the adhesive tape 71 and serving as the bottom surface of the penetrating portion 51. Note that a protective film (not shown) may be formed in advance on the light receiving surface 20a of the optical filter 20 at the time of attachment. As the protective film, for example, a photoresist can be used. Such a protective film can be formed, for example, before dicing the optical member that is the base material of the optical filter 20.

  The subsequent steps are the same as those in the first embodiment except for the lid attaching step. That is, as shown in FIG. 14C, the light receiving element 10 and the lead frame 30 ′ are electrically connected using the wire 40. Here, at least a part of the half-etched region 33a of the lead frame 30 ′ becomes a bonding terminal portion. The bonding terminal portion 33a is electrically connected to the pad electrodes 14a and 14b of the light receiving element 10 shown in FIG.

Next, as shown in FIG. 14D, the lead frame 30 ′ is sandwiched between the upper mold 77 and the lower mold 78, and the space between the upper mold 77 and the lower mold 78 is inserted from the side. Mold resin 45 is injected and filled. Thereby, the light receiving element 10, the optical filter 20, and the wire 40 are resin-sealed. Next, the adhesive tape 71 is removed from the lower surface side of the lead frame 30 ′, and the same processing as in the first embodiment is performed as necessary. Thereafter, the mold resin 45 and the lead frame 30 ′ are diced by a dicing device, and the kerf width 35 is cut. As a result, as shown in FIG. 14E, the mold resin 45 and the lead frame 30 'are cut into individual products and packaged, and the IR light receiving device 150 is completed.
Next, the IR light receiving device 150 and the IR light emitting device 60 manufactured as described above are mounted on the surface 1 a of the wiring board 1. This mounting process is the same as that in the first embodiment, and is performed, for example, by reflow soldering. Through these steps, the photocoupler 200 shown in FIGS. 13A and 13B is completed.

(3) Third Embodiment In the first embodiment described above, for example, as shown in FIG. 1B, the lead frame 30 is formed by overlapping the first lead frame 31 and the second lead frame 36. The case where it is configured has been described. However, in the present invention, the lead frame is not necessarily composed of a plurality of sheets. A single lead frame may be used instead of a plurality of sheets.

  FIG. 15 is a cross-sectional view showing a configuration example of a surface-facing surface-mounting type and vertical-mounting type photocoupler 300 according to the third embodiment of the present invention. As shown in FIG. 15, the photocoupler 300 includes a wiring board 1, an IR light emitting device 60 bonded onto the surface 1 a of the wiring board 1, and the IR light emitting device 60 on the surface 1 a of the wiring board 1. IR light receiving device 250 joined to a position away from the light source, and a light shielding housing (not shown) (see, for example, FIG. 1A). Here, the IR light receiving device 250 is, for example, a sensor device like the IR light receiving device 50 described in the first embodiment, and converts the received IR into an electric signal and outputs the converted electric signal.

  This photocoupler 300 is different from the photocoupler 100 described in the first embodiment in the structure of the IR light receiving device. That is, as shown in FIG. 15, the lead frame 130 of the IR light receiving device 250 is composed of one sheet instead of a plurality of sheets. Even in such a configuration, as in the first embodiment, the positional relationship between the IR light-emitting device 60 and the IR light-receiving device 150 is in the horizontal direction, so that the height of the entire system can be reduced. . Further, the light output from the light emitting surface 61 a of the IR light emitting device 60 is directly incident on the light receiving surface of the optical filter 20. The photocoupler 300 is a surface-facing surface-mount type, and does not require a concave reflecting surface that changes the traveling direction of light between the IR light-emitting device 60 and the IR light-receiving device 50, so that the number of components can be reduced. it can.

Also in the third embodiment, the IR light receiving device 250 is a vertical mounting type because the size relationship between the dimension length L3 in the thickness direction and the dimension length H3 in the height direction is L3 <H3. ing. This reduces the mounting area.
FIGS. 16A and 16B are plan views showing a configuration example of the lead frame 130 according to the third embodiment of the present invention. 16A shows the front surface 130a of the lead frame 130, and FIG. 16B shows the back surface 130b of the lead frame 130. In the lead frame 130 shown in FIGS. 16A and 16B, for example, a copper (Cu) plate is selectively etched from the front surface 130a side and the back surface 130b side by a photolithography technique, and nickel (Ni) is obtained. -It is formed by performing plating (plating) treatment of palladium (Pd) -gold (Au) or the like.

  In FIG. 16A, a white region in the lead frame 130 indicates a through portion 151 that penetrates between the front surface 130a and the back surface 130b, and a hatched region is a region that is half-etched from the front surface 130a side ( That is, a half-etched region) 133a is shown. A gray region indicates a region (that is, a non-etched region) 134a that was not etched by masking the surface 130a with a photoresist or the like during etching.

  Similarly, in FIG. 16B, the white region in the lead frame 130 indicates the through portion 151, and the gray region is non-etched because the back surface 130b is masked with a photoresist or the like during etching. Region 134b is shown. Further, the back surface 130b of the lead frame 130 has no half-etched region and is flat. 16A and 16B is an area (namely, kerf width) 135 that is cut by a dicing blade or the like in a dicing process described later.

17A to 17E are cross-sectional views illustrating a method for manufacturing a photocoupler 300 according to the third embodiment of the present invention. As shown in FIG. 17A, first, the lead frame 130 '
Adhesive tape 71 is affixed to the back surface 130b of. Next, as illustrated in FIG. 17B, the light receiving element 10 is disposed in the through portion 151 of the lead frame 130 ′. Here, the light receiving surface 16b of the light receiving element 10 is attached to the surface of the adhesive tape 71 having the adhesive property and the bottom surface of the penetrating portion 51. As in the first embodiment, a protective film (not shown) may be formed in advance on the light receiving surface 16b of the light receiving element 10 at the time of sticking.

  Next, as shown in FIG. 17C, the light receiving element 10 and the lead frame 130 ′ are electrically connected using a wire 40. Here, at least a part of the half-etched region 133a of the lead frame 130 ′ serves as a bonding terminal portion. The bonding terminal portion 133a is electrically connected to the pad electrodes 14a and 14b of the light receiving element 10 shown in FIG. Next, as shown in FIG. 17 (d), the lead frame 130 ′ is sandwiched between the upper mold 77 and the lower mold 78, and the space between the upper mold 77 and the lower mold 78 is inserted from the side. Mold resin 45 is injected and filled. Thereby, the light receiving element 10 and the wire 40 are resin-sealed.

Next, the adhesive tape 71 is removed from the lower surface side of the lead frame 130 ′, and the same processing as in the first embodiment is performed as necessary. Thereafter, the mold resin 45 and the lead frame 130 ′ are diced by a dicing device, and the kerf width 135 is cut. As a result, as shown in FIG. 17E, the mold resin 45 and the lead frame 130 'are separated into individual products and packaged, and the IR light receiving device 250 is completed.
Next, the IR light receiving device 250 manufactured as described above and the IR light emitting device 60 are mounted on the surface 1 a of the wiring board 1. This mounting process is the same as that in the first embodiment, and is performed, for example, by reflow soldering. Through such steps, the photocoupler 300 shown in FIG. 15 is completed.

(4) Other Embodiments (4.1) In the first embodiment described above, the exposed side surface 31c of the first lead frame 31 and the second lead frame on the bonded surface 49 of the IR light receiving device 50 are used. It has been described that the side surfaces 36c of 36 function as external connection terminal portions. Here, FIGS. 2A and 2C show a case where the external connection terminal portions 31 c and 36 c are separated from each other on the bonded surface 49. However, in the present invention, these may be connected.

  That is, as shown in FIG. 18, on the bonded surface 49, one adjacent external connection terminal portion 31 c and the other external connection terminal portion 36 c may be connected. With such a configuration, the area to be soldered (that is, the total area of the external connection terminal portion) is increased, so that the bonding of the IR light receiving device 50 to the wiring board 1 can be made stronger.

In the form shown in FIG. 18, for example, the back surface 31b of the first lead frame 31 and the front surface 36a of the second lead frame are changed from the form shown in FIGS. 4B and 5A to FIG. It can implement | achieve by changing to the form shown to a) and (b), respectively. On the other hand, the front surface 31a of the first lead frame 31 and the back surface 36b of the second lead frame are not changed and are as shown in FIGS. 4B and 5A.
(4.2) In the first embodiment, for example, in FIG. 1B, the back surface 36 b of the second lead frame and the lid 55 are in contact with each other near the front surface 1 a of the wiring board 1. showed that. However, in the present invention, for example, as shown in FIG. 20A, the back surface 36 b of the second lead frame 36 and the lid 55 may be separated near the front surface 1 a of the wiring board 1.

That is, a concave portion (slit) 56 may be provided in a portion of the lid 55 near the surface 1 a of the wiring substrate 1 and facing the lead frame 30. With such a configuration, in the soldering process, the solder 3 can easily wrap around from the side surface (that is, the external connection terminal portion) 36c of the second lead frame 36 toward the back surface 36b. Since the joint portion by the solder 3 spreads, the joint of the IR light receiving device 50 to the wiring board 1 can be made stronger.
In addition, as shown in FIG. 20B, the recess 56 extends in the X direction and may be provided so as to reach the guide portion 59. If it is such a structure, as shown, for example with the arrow of FIG.20 (b), the joining state by the solder 3 can be confirmed visually.

(4.3) Further, in each of the above-described embodiments, the case where the IR light receiving devices 50, 150, and 250 each include two light receiving elements 10 of the same type has been described. However, in the present invention, the number of light receiving elements included in one IR light receiving device is not limited to two. The number of light receiving elements included in one IR light receiving device may be three or more, or may be one. The number of light receiving elements included in one IR light receiving device can be arbitrarily set in accordance with a desired function.

(4.4) Further, in each of the above embodiments, the light receiving element capable of detecting infrared rays of 2000 nm to 7400 nm is exemplified. However, in the present invention, the light receiving element is not limited to IR detection. In the present invention, the light receiving element may be, for example, an element that detects only ultraviolet rays, or may be an element that detects both ultraviolet rays and infrared rays. Alternatively, it may be an element that detects light outside the ultraviolet or infrared wavelength range.

For example, in the photoelectric conversion element 13 in which an n layer, a π layer, a compound semiconductor layer having a larger band gap than the n layer and the π layer, and a p layer are sequentially stacked on a light transmitting substrate, n When other materials such as AlN, InGaP, InGaAsP, and InAsSb are used for the layer instead of InSb, it is possible to create a light receiving element capable of detecting from ultraviolet rays having a wavelength of about 250 nm to infrared rays having a wavelength of about 12 μm. . In such a case, a photocoupler provided with a light receiving device capable of detecting ultraviolet rays to infrared rays can be provided.
In this case, the optical filter may also have a function of transmitting only ultraviolet rays, for example, or may transmit both ultraviolet rays and infrared rays. The wavelength range in which the optical filter can be transmitted can be arbitrarily set according to the wavelength range in which the light receiving element can be detected.

DESCRIPTION OF SYMBOLS 1 Wiring board 1a Wiring board surface 10 Light receiving element (1st light receiving element, 2nd light receiving element)
DESCRIPTION OF SYMBOLS 11 Light transmissive substrate 12 Light-receiving part 13 Photoelectric conversion element 13a n layer 13b pi layer 13c compound semiconductor layer 13d p layer 14 pad part 14a, 14b pad electrode 15 wiring 16a surface 16b light-receiving surface (back surface)
20 Optical filter (first optical filter, second optical filter)
20a Light receiving surface 30 Lead frame (laminated structure)
31 1st lead frame 31a, 36a, 130a Front surface 31b, 36b, 130b Back surface 31c, 36c Side surface (external connection terminal portion)
32 1st penetration part 33a, 133a Half etching area | region (terminal part for bonding)
33b, 38a, 37b Half-etched regions 34a, 34b, 39a, 39b, 134a, 134b Non-etched regions 35, 135 Calf width 36 Second lead frame 37 Second through-hole 40 Wire 45 Mold resin (package)
46 Adhesive 49 Bonded surfaces 50, 150, 250 IR light receiving device 51, 151 penetrating part (including first region and second region)
55 Lid 56 Plate part 57 Opening (first opening, second opening)
58 concave portion 59 guide portion 60 light emitting device 61 light emitting portion 61a light emitting surface 71 adhesive tape 73, 74 through hole 75 pin 77 upper die 78 lower die 90 housing 91 opening 100, 200, 300 photocoupler

Claims (8)

A wiring board;
A light emitting device bonded on one surface of the wiring board;
A light receiving device bonded to a position away from the light emitting device on one surface of the wiring board,
A photocoupler, wherein a light emitting surface of the light emitting device and a light receiving surface of the light receiving device face each other on one surface of the wiring board. The light receiving device is:
A light receiving element for detecting light;
A lead frame having a penetrating portion;
It has a wire and a sealing part,
The light receiving element is disposed in the penetrating portion of the lead frame, the photoelectric conversion unit of the light receiving element and the lead frame are electrically connected by the wire,
The sealing portion has a light receiving surface of the light receiving element exposed on a surface facing the light emitting device, and
A side surface of the lead frame is exposed as a plurality of terminal portions electrically connected to the wiring substrate in a vertical manner on a surface to be bonded to one surface of the wiring substrate. The photocoupler according to claim 1.   Each of the plurality of terminal portions is symmetrical in plan view with one side of the joined surface and the other side opposite to the one side with the center of the joined surface interposed therebetween. The photocoupler according to claim 2, wherein the photocoupler is arranged. The light receiving device is:
A lid attached to the sealing portion;
An optical filter covering a light receiving surface of the light receiving element,
4. The photocoupler according to claim 2, wherein an opening that penetrates the lid is provided, and the optical filter is accommodated in the opening. 5. The lead frame is
A first lead frame having a first through portion;
A second lead frame having a second penetrating portion,
The first lead frame is disposed on the second lead frame, and the first penetrating portion and the second penetrating portion overlap in plan view,
As the penetrating part, the sealing part is molded in a state where the light receiving element is arranged in a region where the first penetrating part and the second penetrating part overlap in a plan view,
The first side surface of the first lead frame and the second side surface of the second lead frame are exposed as the plurality of terminal portions from the surface to be joined of the molded sealing portion. The photocoupler according to any one of claims 2 to 4, wherein the photocoupler is characterized in that: The light receiving element includes a first light receiving element and a second light receiving element,
The optical filter includes a first optical filter and a second optical filter having characteristics different from those of the first optical filter,
The penetrating portion includes a first region and a second region having a position different from that of the first region,
The opening includes a first opening and a second opening having a different position from the first opening,
The first light receiving element is disposed in the first region;
The second light receiving element is disposed in the second region;
The first optical filter is housed in the first opening;
The photocoupler according to claim 4 or 5, wherein the second optical filter is accommodated in the second opening. The light receiving device is:
A light receiving element for detecting light;
An optical filter covering a light receiving surface of the light receiving element;
A first lead frame having a first through portion;
A second lead frame having a second penetrating portion;
A wire and a sealing part,
The first lead frame is disposed on the second lead frame, and the first penetrating portion and the second penetrating portion overlap in plan view,
The light receiving element and the optical filter are disposed in a region where the first penetrating portion and the second penetrating portion overlap in plan view, and provided on a surface opposite to the light receiving surface of the light receiving element. The sealing portion is molded in a state where the photoelectric conversion portion and the lead frame are electrically connected by the wire,
The surface exposed to the outside of the molded sealing portion, the light receiving surface of the optical filter is exposed from the surface facing the light emitting device, and
A surface exposed to the outside of the molded sealing portion, and a first side surface of the first lead frame and the first surface from a surface to be bonded to one surface of the wiring board 2. The photocoupler according to claim 1, wherein a second side surface of each of the two lead frames is exposed as a plurality of terminal portions that are electrically connected to the wiring board. The light receiving element includes a first light receiving element and a second light receiving element,
The optical filter includes a first optical filter that covers a light receiving surface of the first light receiving element, and a second optical filter that has different characteristics from the first optical filter and covers the light receiving surface of the second light receiving element. Including
The region where the first penetrating portion and the second penetrating portion overlap in plan view includes the first region and the second region having a position different from the first region,
The first light receiving element and the first optical filter are disposed in the first region,
The photocoupler according to claim 7, wherein the second light receiving element and the second optical filter are arranged in the second region.

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