JP6940373B2 - Receiver - Google Patents

Description

The present invention relates to a light receiving device including a light receiving element such as a photodiode, a line sensor, and an image sensor.

As a small light receiving device, there is a device in which a light receiving element such as a photodiode, a line sensor, or an image sensor is mounted on the bottom surface of a concave portion of a wiring board, and the concave portion is closed with a translucent lid. The light receiving element is sealed by electrically connecting the connection pad provided in the recess of the wiring board and the electrode of the light receiving element with a bonding wire and adhering the translucent lid with a sealing resin. .. In addition, some such light receiving devices are provided with a light shielding member for preventing unnecessary light from entering or flare. As the light-shielding member, a plate-shaped member having a window portion whose edge is bent to form a leg is arranged in a recess (see, for example, Patent Document 1), or a light-shielding film is formed on a translucent lid. (See, for example, Patent Document 2 and Patent Document 3) are used.

Japanese Unexamined Patent Publication No. 2004-363511 Japanese Unexamined Patent Publication No. 2006-41270 Japanese Unexamined Patent Publication No. 10-84509

In the conventional light receiving device in which the light-shielding member is arranged in the recess, the leg portion of the light-shielding member must be arranged outside the connection portion between the connection pad and the bonding wire, so that the recess must be enlarged accordingly. Therefore, it was difficult to miniaturize the wiring board and thus the light receiving device. On the other hand, when a translucent lid provided with a light-shielding film is used, the recess can be made smaller. However, if an attempt is made to reduce the outer shape of the wiring board in order to make it smaller, the width of the upper surface of the wiring board around the recess becomes small, and the width of the sealing resin also becomes small, so that the sealing property deteriorates. There was a risk that it would end up.

The light receiving device according to one aspect of the present invention has a rectangular recess on the upper surface in a plan view, and is a wiring conductor including a plurality of connection pads arranged in the recess along the side surface of the recess. A wiring board having a The recess and the opening are provided through a frame-shaped light-shielding plate having an opening above the light-receiving element and a sealing material provided from the upper surface of the wiring substrate to the upper surface of the light-shielding plate. A translucent lid body that is joined by closing the portions is provided, and the support member is a virtual wire that connects the connection portions between the connection pad and the bonding wire and extends in the arrangement direction of the connection pad. and Ri inside near from the position or the phantom line overlap in a plan view, the provided on the corner portion of the recess includes a stepped portion which is a part of the wiring board.

According to the light receiving device of one aspect of the present disclosure, since it has the above configuration, the size of the recess can be reduced and the width of the sealing material can be increased, so that the size and sealing property can be improved. Since it is excellent and it is easy to suppress the height variation of the support member, the thickness of the sealing material on the support member becomes uniform, the sealing property does not vary, and the sealing reliability is improved .

It is a perspective view which shows an example of a light receiving device. It is an exploded perspective view which shows an example of the light receiving device of FIG. (A) is a plan view (top view) of the light receiving device shown in FIG. 2, (b) is a cross-sectional view taken along the line BB of (a), and (c) is a line CC of (a). It is a cross-sectional view in. It is an exploded perspective view which shows the other example of the light receiving device of FIG. (A) is a plan view (top view) of the light receiving device shown in FIG. 4, (b) is a cross-sectional view taken along the line BB of (a), and (c) is a line CC of (a). It is a cross-sectional view in. (A) is a cross-sectional view showing an enlarged part A of FIG. 3 (b), and (b) and (c) are cross-sectional views of a main part of another example.

The light receiving device according to the embodiment of the present disclosure will be described with reference to the accompanying drawings. It should be noted that the distinction between the upper and lower parts in the following description is for convenience, and does not limit the upper and lower parts when the light receiving device is actually used. FIG. 1 is a perspective view showing an example of a light receiving device. FIG. 2 is an exploded perspective view showing an example of the light receiving device of FIG. FIG. 3A is a plan view (top view) showing the translucent lid and the sealing material of the light receiving device shown in FIG. 2 omitted, and FIG. 3B is B- of FIG. 3A. FIG. 3C is a cross-sectional view taken along the line B, and FIG. 3C is a cross-sectional view taken along the line CC of FIG. 3A. FIG. 4 is an exploded perspective view showing another example of the light receiving device of FIG. 5 (a) is a plan view (top view) showing the translucent lid and the sealing material of the light receiving device shown in FIG. 4 omitted, and FIG. 5 (b) is a plan view (top view) of FIG. 5 (a). FIG. 5C is a cross-sectional view taken along the line B, and FIG. 5C is a cross-sectional view taken along the line CC of FIG. 5A. 6 (a) is a cross-sectional view showing an enlarged portion A of FIG. 3 (b), and FIGS. 6 (b) and 6 (c) are cross-sectional views of similar parts of other examples. In FIGS. 1 to 5, the light-shielding plate is hatched (dot-shaped shading) so as to be easily distinguished from the others.

The light receiving device of one aspect of the present disclosure includes a wiring board 1, a light receiving element 2, a light shielding plate 3, and a translucent lid 4. The wiring board 1 has a rectangular recess 1a on the upper surface in a plan view, and has a wiring conductor 1b in the recess 1a including a plurality of connection pads 1b1 arranged along the side surface of the recess 1a. ing. The light receiving element 2 is mounted on the bottom surface of the recess 1a of the wiring board 1, and the electrode 2a of the light receiving element 2 and the connection pad 1b1 of the wiring board 1 are electrically connected by a bonding wire 2c. The light-shielding plate 3 has a frame shape, is supported by a support member 1c arranged in the recess 1a, is arranged at the upper end of the recess 1a, and has an opening 3a above the light receiving element 2. The translucent lid 4 is joined by closing the recess 1a and the opening 3a via a sealing material 4a provided from the upper surface of the wiring board 1 to the upper surface of the light-shielding plate 3. The support member 1c is located at a position where the connection portion between the connection pad 1b1 and the bonding wire 2c is connected to each other and extends in the arrangement direction of the connection pad 1b1 and overlaps with the virtual line i in a plan view or inside the virtual line i. In other words, the support member 1c is not arranged outside the connection portion between the connection pad 1b1 and the bonding wire 2c. In the examples shown in FIGS. 1 to 5, the support member 1c is located at a position overlapping the virtual line i.

According to the light receiving device of one aspect of the present disclosure, since it has the above configuration, no leg portion or the like for supporting the light-shielding member is arranged outside the connection portion between the connection pad 1b1 and the bonding wire 2c. Since it is not necessary to increase the size of the recess 1a in order to arrange the light-shielding plate 3 and the support member 1c, the size of the recess 1a can be reduced. Further, since the sealing material 4a is provided from the upper surface of the wiring board 1 to the upper surface of the light-shielding plate 3, the width of the sealing material 4a is made larger than that of the upper surface of the wiring board 1 located around the recess 1a. Therefore, even the wiring board 1 which is small and has a small upper surface width can have high sealing performance. Therefore, the light receiving device 10 is compact and has excellent sealing properties.

In the examples shown in FIGS. 2 and 3, the recess 1a has two steps. The concave portion 1a, which is square in a plan view, is provided with a step portion in which a portion on the bottom surface side of each inner wall protrudes. The light receiving element 2 is mounted on the bottom surface of the recess 1a, and the connection pad 1b1 is provided on the upper surface (step surface) of the step portion. As a result, the height of the electrode 2a of the light receiving element 2 and the height of the connection pad 1b1 become close to each other, so that the connection by wire bonding is easy. The support member 1c that supports the light-shielding plate 3 is provided on the step portion. The step portion has a frame shape, and the support member 1c is arranged at the four corner portions of the step portion (frame-shaped stepped surface). A connection pad 1b1 is provided between the corners on the step portion. The connection pad 1b1 is a rectangle that is long in the direction from the inside to the outside of the recess 1a, and has a connection portion with the bonding wire 2c at the central portion in the length direction. The virtual lines i that connect the connection portions and extend in the arrangement direction of the connection pads 1b1 are shown at two locations above and to the right of the light receiving element 2 in FIG. 3A. In FIG. 3A, the support member 1c located at the upper left of the light receiving element 2 overlaps with the upper virtual line i. Similarly, the support member 1c located at the lower left overlaps with the virtual line i on the right. Further, the support member 1c also located on the upper right side overlaps with both the upper virtual line i and the right virtual line i. Further, as shown in FIG. 3B, the outer edge of the support member 1c is at the same position as the outer side of the connection pad 1b1 in the side perspective. The support member 1c is not located outside the connection pad 1b1.

The light receiving device 10 of the example shown in FIGS. 4 and 5 has a different form of the support member 1c from the light receiving device 10 of the example shown in FIGS. 2 and 3. The support member 1c includes a step portion 1c2 which is a part of the wiring board 1 provided at a corner of the recess 1a. In the examples shown in FIGS. 4 and 5, a step portion 1c2 is further provided on the four corner portions of the frame-shaped stepped surface. The step portions 1c2 are provided at the four corners of the recess 1a. The joining member 1c1 is arranged on the stepped portion 1c2, the supporting member 1c is formed by the stepped portion 1c2 and the joining member 1c1, and the light-shielding plate 3 is fixed and supported by the supporting member 1c. The support member 1c (joining member 1c1 and step portion 1c2) may not have four corners (corner portions) such as the central portion of the rectangular side of the recess 1a depending on the arrangement of the connection pad 1b1. This also applies when the support member 1c does not include the step portion 1c2 as in the examples shown in FIGS. 2 and 3.

When the support member 1c includes the step portion 1c2, it is easy to suppress the height variation of the support member 1c, so that the thickness of the sealing material 4a on the support member 1c becomes uniform, and the sealing property is not varied. The reliability of the stop is improved. Further, since the step portion 1c2 is formed at the same time as the wiring board 1, it is easy to form the support member 1c having a high height and no height variation.

The sealing material 4a is provided from the upper surface of the wiring board 1 to the upper surface of the light-shielding plate 3, and in this range, between the lower surface of the translucent lid 4 and the upper surface of the light-shielding plate 3 and the upper surface of the wiring board 1. It is filled. Since the lower surface of the translucent lid 4 is flat, the thickness of the sealing material 4a can be adjusted by the height of the upper surface of the light-shielding plate 3 and the height of the upper surface of the wiring board 1.

In the example shown in FIG. 6A, the height of the upper surface of the light-shielding plate 3 and the height of the upper surface of the wiring board 1 are the same. Therefore, the thickness of the sealing material 4a located on the light-shielding plate 3 and the sealing material 4a located on the wiring board 1 are the same. When the sealing material 4a is applied from the upper surface of the wiring board 1 to the upper surface of the light-shielding plate 3 and the translucent lid 4 is placed on the coating material 4a for joining, the coating material 4a is easy to apply and the width of the sealing material 4a. It is easy to suppress the variation of. Since the width of the sealing material 4a has a small variation in the circumferential direction, the sealing property also has a small variation in the circumferential direction, and the light receiving device 10 has an improved sealing property.

In the example shown in FIG. 6B, the height of the upper surface of the light-shielding plate 3 is higher than the height of the upper surface of the wiring board 1. As a result, the thickness of the sealing material 4a located on the upper surface of the wiring board 1 is thicker than the thickness of the sealing material 4a located on the light-shielding plate 3. The thermal stress due to the difference between the coefficient of thermal expansion of the translucent lid 4 and the coefficient of thermal expansion of the wiring substrate 1 (insulating substrate) becomes large at the outer peripheral portion of these joints.
When the height of the upper surface of the light-shielding plate 3 is higher than the height of the upper surface of the wiring board 1, the thickness of the outer peripheral portion of the sealing material 4a where the thermal stress increases can be easily increased. Then, with respect to the thermal stress acting in the surface direction of the translucent lid 4, the sealing material 4 is formed on the step between the upper surface of the light-shielding plate 3 and the upper surface of the wiring board 1.
Since a is caught, it is more effective against peeling between the translucent lid 4 and the wiring board 1 due to thermal stress. Further, since the sealing material 4a is also joined to the outer surface of the light-shielding plate 3, the joining area with the light-shielding plate 3 becomes large. From these facts, the light receiving device 10 has improved sealing reliability.

In the example shown in FIG. 6C, the height of the upper surface of the light-shielding plate 3 is lower than the height of the upper surface of the wiring board 1. As a result, the thickness of the sealing material 4a located on the light-shielding plate 3 is thicker than the thickness of the sealing material 4a located on the wiring board 1. It is possible to improve the sealing property by providing a thick portion without increasing the height of the sealing material 4a. Further, since the sealing material 4a is also joined to the inner side surface of the recess 1a of the wiring board 1, the joining area with the wiring board 1 becomes large. From these facts, the light receiving device 10 is advantageous in reducing the height while improving the sealing property.

The wiring board 1 is an insulating board having a recess 1a provided with a wiring conductor 1b.

The insulating substrate is a basic structural part of the wiring board 1, and has functions such as ensuring mechanical strength as the wiring board 1 and ensuring insulation between a plurality of wiring conductors 1b. The insulating substrate has a rectangular shape including, for example, a square shape and a rectangular shape when viewed from above (in a plan view). The square shape and the rectangular shape do not have to be a strict square shape and a rectangle shape, and include, for example, those having rounded corners, those having a so-called C-plane formed at the corners, and the like. It is set according to the shape of the light receiving element 2 mounted on the wiring board 1 in a plan view.

Regarding the light receiving device 10, if the external electrode 1b3 provided on the lower surface of the insulating substrate of the wiring conductor 1b is electrically connected to the external electric circuit, the mounted light receiving element 2 is electrically connected to the external electric circuit. Will be done. That is, the light receiving element 2 and the external electric circuit are electrically connected to each other via the bonding wire 2c and the wiring conductor 1b. For example, when the light receiving element 2 is an image sensor and the light receiving device 10 is an image pickup device, the external electric circuit is an electric circuit included in a circuit board mounted on a device such as a digital camera.

The insulating substrate has a shape in which a frame-shaped portion is laminated on a flat plate portion and integrated, and has a shape having a recess 1a for accommodating the light receiving element 2 on the upper surface. The shape of the recess 1a in a plan view is also rectangular. As described above, the recess 1a has two steps in the examples shown in FIGS. 2 and 3, and in the examples shown in FIGS. 4 and 5, the entire recess 1a has two steps and further steps at the four corners. A portion 1c2 is provided to form three stages. It is not necessary to provide the step portion, but as described above, the step portion makes it easier to connect by wire bonding. Therefore, the step portion is provided according to the light receiving element 2 (electrode 2a). In the examples shown in FIGS. 1 to 5, the electrodes 2a of the light receiving element 2 are arranged along the four sides of the upper surface of the light receiving element 2. Is provided. When the electrodes 2a of the light receiving element 2 are arranged along the two opposite sides of the upper surface of the light receiving element 2, the step portion may be provided only on the two opposite inner surfaces of the recess 1a.

The dimensions of the insulating substrate are, for example, a rectangle having a side length of 5 mm to 10 mm and a thickness of 1 mm to 3 mm. The dimensions of the recess 1a depend on the size of the light receiving element 2 housed in the recess 1a and mounted on the bottom surface. For example, the length of one side of the rectangle is 3 mm to 9 mm and the depth is 0.5 mm to 2 mm. Therefore, the width of the outer portion of the recess 1a, which is the upper surface of the wiring board 1, is assumed to be as small as 1 mm or less, and the light receiving device 10 is made as small as possible. When the recess 1a has a step, the width of the step (the length from the inner surface of the recess 1a) is, for example, 0.5 mm to 1.5 mm, and the height of the recess 1a from the bottom surface is 0.2 mm to. It is 1.2 mm.

The insulating substrate is formed by laminating a plurality of insulating layers made of an insulating material including a ceramic material such as an aluminum oxide sintered body, a glass ceramic sintered body, a mullite sintered body, or an aluminum nitride material sintered body. ing. In the examples shown in FIGS. 3 and 5, the number of insulating layers is 6, but the number of layers of the insulating layer is not limited to these.

The insulating substrate can be manufactured as follows, for example, when it is made of an aluminum oxide sintered body. That is, first, a ceramic green sheet to be an insulating layer is produced. Raw material powders such as aluminum oxide and silicon oxide are formed into a sheet together with an appropriate organic binder and an organic solvent to prepare a plurality of square sheet-shaped ceramic green sheets. Next, these ceramic green sheets are laminated to prepare a laminated body. The recess 1a may be provided with a through hole in the ceramic green sheet using a mold or the like. When the connection pad 1b1 is provided on the upper surface (stepped surface) of the stepped portion, a through hole smaller than the through hole for the recess 1a may be provided on another ceramic green sheet. The step portion 1c2 that is a part of the support member 1c can also be formed by providing a through hole in the ceramic green sheet. After that, an insulating substrate can be manufactured by firing this laminate at a temperature of 1300 to 1600 ° C.

The wiring board 1 including the insulating board can also be manufactured as a multi-layer board in which a plurality of board regions serving as such a wiring board 1 are arranged on the mother board. It is also possible to more efficiently manufacture the plurality of wiring boards 1 by dividing the mother substrate including the plurality of substrate regions into each substrate region. In this case, a groove for division may be provided along the boundary of the substrate region of the mother substrate. Further, after mounting the light receiving element 2 on each substrate region of the multi-layer board, the light receiving element 2 may be divided to obtain a plurality of light receiving devices 10.

Wiring conductors 1b are provided on the surface and inside of the insulating substrate. For example, in the examples shown in FIGS. 1 to 6, a connection pad 1b1 for connecting to the light receiving element 2 is provided in the recess 1a. Further, an external electrode 1b3 for connecting to an external electric circuit is provided on the lower surface of the insulating substrate. The connection pad 1b1 and the external electrode 1b3 are electrically connected by an internal wiring 1b2 including a through conductor provided inside the insulating substrate and an internal wiring layer. The penetrating conductor penetrates the insulating layer, and the internal wiring layer is arranged between the insulating layers. The external electrode 1b3 may be provided from the lower surface to the side surface or on the side surface instead of the lower surface of the insulating substrate.

The wiring conductor 1b includes, for example, tungsten (W), molybdenum (Mo), manganese (Mn), copper (Cu), silver (Ag), palladium (Pd), gold (Au), platinum (Pt), and nickel (Ni). ) Or a metal such as cobalt (Co), or a metal material of an alloy containing these metals is mainly contained as a conductor material. Such a metal material is provided on the surface of the insulating substrate as a metal layer such as a metallized layer or a plating layer. The metal layer may be one layer or a plurality of layers. In addition, it is provided inside the insulating substrate by metallizing.

When the connection pad 1b1, the internal wiring 1b2, and the external electrode 1b3 of the wiring conductor 1b are, for example, a metallized layer of tungsten, a metal paste prepared by mixing tungsten powder with an organic solvent and an organic binder is used as an insulating substrate. The ceramic green sheet can be formed by printing at a predetermined position by a method such as a screen printing method and firing. Further, among these, even if a plating layer such as nickel and gold is further adhered to the exposed surface of the metallized layer serving as the connection pad 1b1 and the external electrode 1b3 by a plating method such as an electrolytic plating method or an electroless plating method. good. In this case, when the wiring board 1 or the light receiving device 10 is manufactured in the form of a large number of boards as described above, if the wiring conductors in the plurality of board regions are electrically connected to each other, the plurality of wiring boards 1 It is also possible to collectively coat the wiring conductors of the above with a plating layer. Further, the through conductor of the internal wiring 1b2 is formed by providing a through hole at a predetermined position on the ceramic green sheet prior to printing the above metal paste and filling the through hole with the same metal paste as above. can do.

The insulating substrate of the wiring board 1 may have an insulating layer made of resin. Even in this case, the light receiving device 10 having the same effect as described above can be obtained. It can be manufactured by using a conventionally known method for manufacturing a resin wiring board.

Examples of the light receiving element 2 include a photodiode, a line sensor, an image sensor, and the like. These light receiving elements 2 are elements that convert an optical signal into an electric signal. For example, in a photodiode, the storage capacity changes according to the input of light. In the examples shown in FIGS. 1 to 5, a light receiving region 2b (a region surrounded by a two-dot chain line in each figure) is provided in the central portion on the upper surface of the light receiving element 2, and electrodes 2a are arranged on the outer peripheral portion. ..

The light receiving element 2 is placed on the bottom surface of the recess 1a, for example, and is joined by a joining material (not shown). The electrode 2a on the outer peripheral portion of the upper surface and the connection pad 1b1 portion provided on the stepped surface are electrically connected by a bonding wire 2c made of Au, aluminum (Al), or the like. The electric signal detected and converted by the light receiving element 2 is electrically led out to an outer surface such as the lower surface of the insulating substrate via the bonding wire 2c and the wiring conductor 1b.

As the joining material for joining and fixing the light receiving element 2 to the wiring board 1 (the bottom surface of the recess 1a), a brazing material containing solder or a resin adhesive such as glass or epoxy resin can be used. When the bonding material is a resin adhesive, thermal stress or the like can be absorbed by the bonding material by using a more flexible material such as silicone rubber or urethane rubber. When the bonding material is a brazing material containing solder, a bonding metal layer formed of a metal film such as a plating film or a metallized layer is provided on the bottom surface of the recess 1a of the wiring board 1.

The light-shielding plate 3 is a plate-like material made of a material that does not transmit light received by the light-receiving element 2, for example, visible light when the light-receiving element 2 is an image sensor for a digital camera. Further, it has a frame shape having an opening 3a for transmitting light. The opening 3a is located above the light receiving element 2. More specifically, it is provided at a position corresponding to the light receiving region 2b of the light receiving element 2. In the examples shown in FIGS. 1 to 5, an electrode 2a is arranged on the outer peripheral portion of the upper surface of the light receiving element 2, and a light receiving region 2b is provided inside the electrode 2a. Therefore, the opening 3a of the light-shielding plate 3 is located above the central portion of the light-receiving element 2, and the outer peripheral portion of the light-receiving element 2 and the light-shielding plate 3 overlap each other in a plan view. In order to block unnecessary light as much as possible, the size of the opening 3a is set to be about the same size as the light receiving region 2b of the light receiving element 2. In addition to transmitting necessary light and receiving it by the light receiving element 2, it is possible to effectively prevent unnecessary external light from entering the light receiving element 2 and diffuse reflection of light in the recess 1a. It is possible to provide a light receiving device 10 having excellent light receiving characteristics.

As described above, the light-shielding plate 3 is made of a material that does not transmit the light received by the light-receiving element 2. For example, a metal, ceramics, or a resin can be used, and a composite material thereof, a plurality of types of resins, or the like may be used. Further, it is preferable that the light reflected on the surface of the light receiving element 2 is reflected on the lower surface of the light shielding plate 3 (the surface facing the light receiving element 2) so that it does not enter the light receiving element 2 again. For example, the light-shielding plate 3 may be provided with a resin film or the like that absorbs light on the lower surface of the metal plate. At this time, the light-shielding film is not provided on the lower surface of the light-shielding plate 3 in contact with the support member 1c, so that the bondability with the support member 1c described later can be improved. From the same viewpoint, when the light-shielding plate 3 is made of a resin that does not transmit light, a metal film can be partially provided in order to improve the bondability with the support member 1c and the bondability with the sealing material 4a. .. Further, a light-shielding film made of resin may be provided on the surface of the translucent resin. Alternatively, the light-shielding plate 3 may be provided with a light-shielding film of a metal thin film on the upper surface of the plate made of resin and a light-shielding film (or antireflection film or light absorption film) made of resin on the lower surface.

At least the lower surface of the light-shielding plate 3 can be made insulating. The light-shielding plate 3 may be formed of an insulating resin, or a film of an insulating resin may be provided on the lower surface of the metal plate. When such a light-shielding plate 3 is used, even if the light-shielding plate 3 comes into contact with the bonding wire 2c, there is no short circuit between the plurality of bonding wires 2c. Therefore, it is effective in reducing the height of the light receiving device 10.

Regarding the dimensions (outer dimensions) of the light-shielding plate 3, the size in a plan view is about the same as the size of the recess 1a of the wiring board 1. When arranging the light-shielding plate 3, the shape and size of the light-shielding plate 3 in a plan view are 0 from the opening size of the recess 1a so that the light-shielding plate 3 is not scraped due to contact with the wiring board 1 and dust is not generated. .It has a rectangular shape that is about 1 to 1 mm smaller. That is, a clearance of about 0.05 mm to 0.5 mm is provided between the light-shielding plate 3 and the inner surface of the recess 1a. By doing so, the possibility that the above-mentioned dust is generated is reduced, and the alignment of the light-shielding plate 3 becomes easy. Further, when the sealing material 4a is provided from the upper surface of the wiring board 1 to the upper surface of the light-shielding plate 3, for example, a liquid resin to be the sealing material 4a penetrates into the recess 1a through this clearance to receive light from the light receiving element 2. The possibility of covering the region 2b is reduced. The inner dimension (dimension of the opening 3a) of the light-shielding plate 3 is a dimension corresponding to the size of the light-receiving element 2 (the light-receiving region 2b) as described above, and is, for example, a rectangle having a side length of 1 mm to 7 mm. The shape. The thickness of the light-shielding plate 3 depends on the depth of the recess 1a, the thickness of the light receiving element 2, and the like, but is, for example, about 0.1 mm to 0.5 mm.

The light-shielding plate 3 is supported and fixed by a support member 1c provided at a corner of the recess 1a. As the support member 1c, for example, a gold bump can be used. The gold bump not only supports the light-shielding plate 3, but also functions as a joining member for joining the wiring board 1 and the light-shielding plate 3. For example, gold bumps are provided at the four corners of the step portion as in the examples shown in FIGS. 2 and 3, and a metal light-shielding plate 3 is placed on the gold bumps, and heating and pressurization or ultrasonic vibration are applied. By doing so, the light-shielding plate 3 can be fixed to the wiring board 1. At this time, the upper surface of the light-shielding plate 3 can be made parallel to the upper surface of the wiring board 1 and the height of the upper surface of the light-shielding plate 3 can be adjusted by pressing the light-shielding plate 3. In order to improve the bonding strength between the gold bump and the insulating substrate, it is preferable to provide a metal film similar to the wiring conductor 1b on the surface of the insulating substrate. Since it is advantageous in terms of cost and strength as a support member to reduce the size of the gold bump, the support member 1c includes the step portion 1c2 as in the examples shown in FIGS. 4 and 5. As such, the gold bump can be the joining member 1c1 on it. In the examples shown in FIGS. 4 and 5, the joining member 1c1 having a relatively large top view is provided one on each step 1c2, but is small on the step 1c2. May be provided one or more.

The support member 1c and the joining member 1c1 of the support member 1c may be bumps made of a metal other than gold, for example, solder, which is advantageous in terms of cost as compared with gold bumps. Further, as the support member 1c and the joining member 1c1 of the support member 1c, those made of resin can also be used. In this case, the resin support member main body may be adhered to the wiring board 1 and the light-shielding plate 3 with an adhesive, or for example, a pillar made of epoxy resin in a semi-effect state (B stage state) may be adhered to the wiring board 1. It may be joined by placing the light-shielding plate 3 on the mounting surface and heating the light-shielding plate 3. When the support member 1c includes the step portion 1c2, a liquid resin is applied or a semi-cured resin is placed on the step portion 1c2, and a light-shielding plate 3 is placed on the step portion 1c2 to cure the resin. By doing so, the light-shielding plate 3 can be fixed to the wiring board 1.

The relationship between the height of the upper surface of the light-shielding plate 3 and the height of the upper surface of the wiring board 1 can be set by the height of the support member 1c and the thickness of the light-shielding plate 3. As described above, the height of the support member 1c can also be adjusted by the pressing force when the light-shielding plate 3 is attached. The difference between the height of the upper surface of the light-shielding plate 3 and the height of the upper surface of the wiring board 1 can be, for example, about 0.05 mm to 0.5 mm.

The light receiving element 2 is sealed and protected by a translucent lid 4. The translucent lid 4 is joined to the wiring board 1 by closing the recess 1a and the opening 3a of the light-shielding plate 3 via a sealing material 4a provided from the upper surface of the wiring board 1 to the upper surface of the light-shielding plate 3. ing.

The translucent lid 4 is a plate-like material made of a material that transmits light received by the light receiving element 2 such as glass, sapphire, or resin. The dimensions of the translucent lid 4 in a plan view are about the same as the dimensions of the insulating substrate, and the thickness can be, for example, 0.2 mm to 1 mm.

As the sealing material 4a, a brazing material containing a resin adhesive, glass, and solder can be used. When the sealing material 4a is a brazing material, a bonded metal layer formed of a metal film such as a plating film or a metallized layer is provided on the upper surface of the wiring substrate 1 and the outer edge of the lower surface of the translucent lid 4. When the light-shielding plate 3 is made of a material having low wettability (bondability) of the brazing material such as resin or ceramics, a bonded metal layer is also provided on the outer edge of the upper surface of the light-shielding plate 3. When the sealing material 4a is a brazing material, the sealing material wets and spreads on the surface of the bonded metal layer, and does not wet and spread on the insulating layer, that is, on the inner surface of the recess 1a and the like. Therefore, as described above, the sealing material 4a does not invade the inside of the recess 1a from the clearance between the light-shielding plate 3 and the inner surface of the recess 1a. Further, since the brazing material itself has a light-shielding property, external light does not enter from the clearance. When the sealing material 4a is a glass or resin adhesive, a material having a reduced light transmittance can be used as a material containing a colorant such as a pigment. Further, when the sealing material 4a is a glass or resin adhesive, the penetration of the sealing material 4a into the clearance as described above can be suppressed by adjusting the viscosity thereof. The resin adhesive or glass can include a ceramic filler to reduce light transmission and adjust viscosity. When the sealing material 4a is a resin adhesive, an ultraviolet curable resin can be used. Since the light-shielding plate 3 is not on the sealing material 4a, it can be cured by irradiating the ultraviolet-curable resin through the translucent lid 4. Compared with the case of using a thermosetting resin, the influence of heat on the light receiving element 2 is small, and the thermal stress generated when the light receiving element 2 is heated and cured and then cooled is the residual stress inside the sealing material 4a or the like. Never exists as.

As for the dimensions of the sealing material 4a, the outer dimensions in a plan view are the same as those of the wiring board 1, and the inner dimensions are smaller than the recess 1a of the wiring board 1 and larger than the inner dimensions of the light-shielding plate 3 (the dimensions of the opening 3a). Just do it. Specifically, for example, the outer dimension may be a rectangle having a side length of 5 mm to 10 mm, and the inner dimension may be a rectangle having a side length of 1.5 mm to 8 mm. At this time, the width of the sealing material 4a is 1 mm to 3.5 mm, which is larger than the width of the upper surface of the wiring board 1 described above. The thickness of the sealing material 4a can be, for example, about 0.1 mm to 0.8 mm.

The wiring board 1 and the translucent lid 4 can be joined by the sealing material 4a, for example, as follows. A liquid resin adhesive or a precursor such as a glass paste or a brazing material paste to be a sealing material 4a is applied from the upper surface of the wiring board 1 to the outer edge of the upper surface of the light-shielding plate 3 by clean printing or a dispenser. A translucent lid 4 is placed on the transparent lid 4, and the precursor is cured by heating or curing by ultraviolet irradiation, or by cooling after melting by heating, so that the precursor is transparent to the wiring substrate 1 via the sealing material 4a. The optical lid 4 is joined to form a light receiving device 10. Instead of the liquid resin adhesive or the brazing paste, a semi-cured resin sheet or a plate (foil) -shaped brazing preform can also be used.

1 ... Wiring board 1a ... Recessed portion 1b ... Wiring conductor 1b1 ... Connection pad 1b2 ... Internal wiring 1b3 ... External electrode 1c ... Support member 1c1 ... Joining member 1c2 ... Step 2 ... Light receiving element 2a ... Electrode 2b ... Light receiving area 2c ... Bonding wire 3 ... Shading plate 3a ... Opening 4 ... Translucent lid 4a ...・ Encapsulant 10 ・ ・ ・ Light receiving device

Claims (4)

A wiring board having a rectangular recess on the upper surface in a plan view and having a wiring conductor including a plurality of connection pads arranged along the side surface of the recess in the recess.
A light receiving element mounted on the bottom surface of the recess and electrically connected to the connection pad by a bonding wire.
A frame-shaped light-shielding plate that is supported by a support member arranged in the recess and is arranged at the upper end of the recess and has an opening above the light receiving element.
A translucent lid bonded to the wiring board by closing the recess and the opening via a sealing material provided from the upper surface of the wiring board to the upper surface of the light-shielding plate.
Is equipped with
Wherein the support member, Ri inside near from the position or the virtual line overlap in phantom in plan view and extending in the direction of arrangement of the connection pads by connecting the connection portions between the bonding wire and the connecting pads, the recess A light receiving device including a step portion which is a part of the wiring board, which is provided at a corner portion of the wire. The light receiving device according to claim 1, wherein the height of the upper surface of the light-shielding plate and the height of the upper surface of the wiring board are the same. The light receiving device according to claim 1, wherein the height of the upper surface of the light-shielding plate is higher than the height of the upper surface of the wiring board. The light receiving device according to claim 1, wherein the height of the upper surface of the light-shielding plate is lower than the height of the upper surface of the wiring board.

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