JP2010098376A - Solid-state imaging device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a solid-state imaging device picking up an excellent image by preventing a hot state of a solid-state imaging element caused by heat generation of a signal reading circuit of the solid-state imaging element. <P>SOLUTION: This solid-state imaging device is provided with: a semiconductor substrate 20 having signal reading circuits 7-11 for reading signals of a plurality of light reception pixels; a wiring board 50 having a wiring pattern 59 in a position facing the signal reading circuits 7-11; and intermediate wiring layers 22, 23, intermediate wiring contacts 29, a surface wiring layer 3, metal bumps 40, a spreader 59, and wiring board contacts 52, which are used as connection members for thermally connecting the signal reading circuits 7-11 to the wiring board 50 at least in the above position. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a solid-state imaging device.

  Conventionally, solid-state imaging devices represented by CCD image sensors and CMOS image sensors have been widely used in imaging devices such as video cameras and digital cameras. The solid-state image sensor includes a light-receiving pixel section in which a plurality of light-receiving pixels that photoelectrically convert an optical image of a subject formed through an imaging lens into an electric signal for each light-receiving pixel on the same semiconductor substrate, and each light-receiving pixel And a signal readout circuit portion that outputs the electrical signal to the outside of the semiconductor substrate after performing predetermined signal processing.

As an example of a solid-state imaging device using such a solid-state imaging device, Patent Document 1 describes a solid-state imaging device and a manufacturing method thereof. The solid-state imaging device described in Patent Document 1 includes a solid-state imaging device provided with a connection portion at a peripheral portion of an imaging region that is a light-receiving pixel unit, and a transparent cap for protecting the individual imaging device, A lead formed on the surface of the first flexible substrate is connected to a part of the connection part, and a lead formed on the surface of the second flexible substrate is connected to another part of the connection part, The gap between the periphery of the imaging region and the cap is sealed so that an airtight space is formed near the imaging region.
According to the solid-state imaging device described in Patent Document 1, by sealing the periphery of the imaging region and the cap so that an airtight space is formed near the imaging region of the solid-state imaging element, Reliability can be ensured by preventing condensation on the imaging area and deterioration of imaging characteristics.
Japanese Patent No. 3355881

In recent years, in order to reduce the size of a solid-state imaging device, there has been a demand for higher functionality of a signal readout circuit disposed on the same semiconductor substrate as the light receiving pixel portion of the solid-state imaging device. In addition, in order to increase the definition of the captured image, it is required to increase the number of light receiving pixels of the solid-state image sensor. It is known that the amount of heat generated by the signal readout circuit increases due to the increase in the scale of the circuit accompanying the increase in the functionality of the signal readout circuit of the solid-state imaging device and the increase in the driving frequency of the signal readout circuit accompanying the increase in the number of pixels. It has been.
However, in the solid-state imaging device described in Patent Document 1 and the manufacturing method thereof, the heat generated by the signal readout circuit of the solid-state imaging device is diffused inside the solid-state imaging device, and is transmitted through the connection portion provided in the solid-state imaging device. 1, 2 The heat was radiated to the flexible substrate. In the heat radiation by such a heat transfer path, since the heat radiation efficiency is low, a large amount of heat diffuses inside the solid-state image sensor, and the solid-state image sensor is in a high temperature state. In addition, since the structure is hermetically sealed with a cap having low heat transfer efficiency, the heat radiated from the surface of the solid-state image sensor is trapped in this air-tight space, and the high-temperature state of the solid-state image sensor is maintained. . The high-temperature state of the solid-state imaging device as described above has a problem in that the unexpected thermal noise and dark current of the light-receiving pixels are increased, which deteriorates the performance of the solid-state imaging device and causes deterioration of the captured image. .

  The present invention has been made in view of the above-described circumstances, and an object thereof is solid-state imaging capable of capturing a good image by preventing a high-temperature state of the solid-state imaging element due to heat generation of a signal readout circuit of the solid-state imaging element. To provide an apparatus.

In order to solve the above problems, the present invention proposes the following means.
The solid-state imaging device of the present invention includes a semiconductor substrate having a signal readout circuit for reading out signals from a plurality of light receiving pixels, a wiring substrate having a wiring pattern at a position facing the signal readout circuit, and at least the signal at the position. And a connecting member thermally connected to the reading circuit and the wiring board.

According to the present invention, the signal readout circuit and the wiring board are connected by the thermally connected connecting member, and the heat generated by the signal readout circuit is transmitted to the wiring board through the connecting member.
Further, since the wiring board is disposed at a position facing the signal readout circuit, the connecting member can connect the heat transfer path between the signal readout circuit and the wiring board at the shortest distance. As a result, the heat generated by the signal readout circuit is quickly transmitted to the wiring board, preventing diffusion of heat to the light receiving pixels, and effectively preventing unexpected thermal noise and dark current.

In the solid-state imaging device of the present invention, it is desirable that the connection member further has an electrical connection function.
In this case, the operation of the solid-state imaging device can be stabilized by sharing the potentials of the signal read / read circuit on the semiconductor substrate and the wiring substrate.

In the solid-state imaging device of the present invention, it is desirable that a plurality of the connecting members are arranged.
In this case, since the heat transfer path for transferring the heat generated by the signal readout circuit to the wiring board increases, the heat dissipation efficiency can be improved.

In addition, it is desirable that a plurality of solid-state imaging devices of the present invention are arranged at predetermined intervals with respect to the signal readout circuit.
In this case, a plurality of connecting members are arranged at predetermined intervals with respect to the signal readout circuit, so that a heat transfer path can be individually provided for each of the signal readout circuits.
Further, the heat generated by the signal readout circuit is diffused to any one of the connection members arranged at predetermined intervals, is dispersed by each of the plurality of connection members, and is transmitted to the wiring board. As a result, the heat generated by the signal readout circuit is evenly transmitted, thereby reducing the heat bias in the signal readout circuit and suppressing the performance variation due to the temperature due to the arrangement position of the circuit.

Further, in the solid-state imaging device of the present invention, the connection member has a surface wiring layer disposed on the surface of the semiconductor substrate, and the wiring pattern disposed on the surface wiring layer and the surface of the wiring substrate; It is desirable to have metal bumps that are thermally connected to.
In this case, a connection member capable of simultaneously performing electrical connection and thermal connection can be formed by a general manufacturing process. Therefore, it is not necessary to provide an additional process for heat dissipation, and the time and cost for manufacturing the solid-state imaging device can be suppressed.

In the solid-state imaging device of the present invention, the connection member further includes an intermediate wiring layer and an intermediate wiring contact interposed between the readout circuit and the surface wiring layer inside the semiconductor substrate, It is desirable that the signal readout circuit, the intermediate wiring layer, and the surface wiring layer are connected through a wiring contact.
In this case, a connection member capable of simultaneously performing electrical connection and thermal connection can be formed by a general manufacturing process. Therefore, it is not necessary to provide an additional process for heat dissipation, and the time and cost for manufacturing the solid-state imaging device can be suppressed.
In addition, the intermediate wiring layer, the intermediate wiring contact, and the surface wiring layer have higher heat transfer efficiency than the insulating layer for electrically insulating the intermediate wiring layers, thereby preventing heat diffusion to the light receiving pixels. Unexpected thermal noise and dark current can be effectively suppressed.

In the solid-state imaging device of the present invention, it is desirable that the surface wiring layer is disposed so as to cover the signal readout circuit and has a light shielding function.
In this case, the surface wiring layer blocks light from entering the signal readout circuit, so that unnecessary light can be prevented from being mixed, and malfunction of each circuit due to this can be prevented.

In the solid-state imaging device of the present invention, it is preferable that the connection member further includes a wiring board contact connected to a wiring pattern of a front surface and a back surface so as to penetrate the wiring board.
In this case, the heat transferred to the back surface of the wiring board is transferred to the front surface of the wiring board by the wiring board contact. As a result, the heat generated by the signal readout circuit is diffused on both sides of the wiring board, so that the heat radiation area to the outside can be increased. For this reason, the heat transmitted to the wiring board can be efficiently radiated, and the diffusion of heat to the light receiving pixels can be prevented, and the occurrence of unexpected thermal noise and dark current can be effectively suppressed.

In the solid-state imaging device of the present invention, the wiring board has a through hole formed so as to surround a peripheral portion of the light receiving pixel, and one surface of the wiring board faces the light receiving pixel. It is preferable to further include a flat cap that is disposed and seals the through hole.
In this case, since the airtight space is not included in the opposing position of the signal readout circuit because the through hole of the wiring board is formed so as to surround the light receiving pixels, the amount of heat trapped in the airtight space can be greatly reduced. Make it possible. Therefore, it is possible to effectively prevent the occurrence of unexpected thermal noise and dark current by preventing the light receiving pixel from being in a high temperature state.

  According to the solid-state imaging device of the present invention, the signal readout circuit and the wiring pattern are arranged to face each other, and the connection member that thermally connects the signal readout circuit and the wiring board at least at the position is provided. Thus, it is possible to provide a solid-state imaging device capable of capturing a good image by preventing the high-temperature state of the solid-state imaging device due to heat generation of the signal readout circuit by dissipating heat generated by the signal readout circuit to the wiring board. Can do.

(First embodiment)
The solid-state imaging device according to the first embodiment of the present invention will be described below with reference to FIGS.

  As shown in FIG. 1, the solid-state imaging device 100 includes a solid-state imaging device 1 having a light-receiving pixel unit 2 for capturing an image, a wiring board 50 that is thermally and electrically connected to the solid-state imaging device 1, And a cap 71 disposed at a position facing the light receiving pixel unit 2 with the wiring board 50 interposed therebetween. The solid-state imaging device 1 and the wiring board 50 are thermally and electrically connected by metal bumps 40 and fixed by an adhesive 41.

  In addition, a through hole 51 is formed between the light receiving pixel portion 2 and the cap 71 in the wiring substrate 50, and the cap 71 is fixed to the wiring substrate 50 with an adhesive 70 surrounding the periphery of the through hole 51. The cap 71 is made of transparent glass, resin, or the like, and transmits light and enters the light receiving pixel portion 2. The metal bump 40 of this embodiment is made of gold, but other metals, alloys, solders, or the like can be used.

  Further, a wiring pattern such as copper (not shown) is formed on both surfaces of the wiring board 50 on the wiring board 50, and is thermally and electrically connected by wiring board contacts 52. Here, the wiring board contact 52 may be a through hole, a stack via, or the like used for general board wiring layer connection, but is not limited thereto. Moreover, when it comprises with a through hole, it is also possible to fill the interior space with a metal solder.

  As shown in FIG. 2, the solid-state imaging device 1 includes a light receiving pixel unit 2 in which a plurality of light receiving pixels 2a are arranged in a matrix, signal readout circuits 5 to 11 electrically connected to the light receiving pixel unit 2, and an external And a plurality of electrode pads 4 for thermal and electrical connection. The signal readout circuits 5 to 11 are arranged on the same semiconductor substrate as the light receiving pixel unit 2. Among these, the signal readout circuits 6 to 11 are, for example, a TG (timing generator) circuit 6 that generates a control signal for driving the signal readout circuits 5 to 11 of the solid-state imaging device 1, and an analog output signal of the light receiving pixel 2 a. A CDS (correlated double sampling) circuit 7 that removes noise components mixed in the signal, an SR (shift register) circuit 8 that selectively reads the analog output signal obtained by CDS, and a PGA (program that amplifies the output signal of the SR circuit 8) (Gain amplifier) circuit 9, ADC (analog / digital converter) circuit 10 that converts an amplified analog signal output from the PGA circuit 9 into a digital signal, and an output circuit that outputs the digital signal output from the ADC 10 to the outside of the solid-state imaging device 1 11 consists of. Here, the CDS circuit 7 and the SR circuit 8 are each composed of a CDS unit circuit 7a and an SR unit circuit 8a, and the numbers corresponding to the light receiving pixels 2a are arranged. The signal readout circuit 5 performs a reset operation for resetting unnecessary charges accumulated in the light receiving element 2a, an accumulation operation for photoelectrically converting an optical signal into an electrical signal, and a readout operation for amplifying and converting the accumulated charge into a voltage for reading. Is a vertical scanning circuit that selectively performs the above. Since the signal readout circuits 6 to 11 operate at a drive frequency that is higher than that of the vertical scanning circuit, the signal readout circuits 6 to 11 are main heat sources of the solid-state imaging device 1.

As further shown in FIG. 2, a surface wiring layer 3 is provided on the surface layer of the solid-state imaging device 1 so as to cover the signal readout circuits 6 to 11 as heat generation sources. Bump positions 42 for arranging metal bumps 40 are defined on the surface wiring layer 3, and these positions are schematically indicated by white circles. A plurality of bump positions 42 are arranged so as to be separated on the surface of the surface wiring layer 3. Although the arrangement of the bump positions 42 can be set to an appropriate position, it is desirable that the number of bump positions 42 is large. This is because a large number of heat transfer paths to the wiring substrate 50 can be secured and the heat dissipation efficiency can be improved.
Here, the surface wiring layer 3 is made of a metal such as aluminum or copper, or an alloy, and can be formed by a general semiconductor manufacturing process.

  The signal readout circuits 6-11 and the surface wiring layer 3 are thermally and electrically connected by a plurality of intermediate wiring contacts 29 arranged at predetermined intervals in each of the signal readout circuits 6-11. For example, in the present embodiment, one intermediate wiring contact 29 is provided to each of the CDS unit circuit 7a and SR unit circuit 8a in the CDS circuit 7 and SR circuit 8, but a plurality of intermediate wiring contacts 29 are arranged. Also good. The intermediate wiring contact 29 may be a contact plug such as tungsten used for general semiconductor wiring interlayer connection, but is not limited thereto. Further, the arrangement of the intermediate wiring contacts 29 can be set to an appropriate position, but it is desirable that the number of arrangement is large. This is because a large number of heat transfer paths to the surface wiring layer 3 can be secured and the heat radiation efficiency can be improved.

  FIG. 3 is a view showing the surface of the wiring board 50. The wiring board 50 is a two-layer flexible board. In addition, the wiring substrate 50 is provided with a ground (GND) pattern 53 having a ground (GND) potential covered with, for example, copper foil on the surface. The edge portion 58 of the GND pattern 53 is formed so as to surround the periphery of the through hole 51, and has a predetermined adhesion region for placing a cap 71 (see FIG. 1) that seals the through hole 51. . Further, the wiring board 50 is provided with a wiring board contact 52 having one end exposed on the surface of the GND pattern 53 and thermally and electrically connected to the GND pattern 53.

  FIG. 4 is a view showing the back surface of the wiring board 50 shown in FIG. The other end of the wiring board contact 52 shown in FIG. The other end of the wiring board contact 52 is thermally and electrically connected to a spreader 59 made of, for example, copper foil as a board wiring pattern. The wiring substrate contacts 52 can be arranged at an appropriate position, but it is desirable that the number of the wiring board contacts 52 be large. This is because a large number of heat transfer paths from the spreader 52 to the GND pattern 53 can be secured and the heat dissipation efficiency can be improved.

  Further, a substrate wiring pattern 54 made of, for example, copper foil is formed at a position that surrounds the spreader 59 and the through-hole 51 and faces the electrode pad 4 (see FIG. 2) of the solid-state imaging device 1. The board wiring pattern 54 is arranged so as to extend from the center side of the wiring board 50 to the end of the wiring board 50 and can be connected to, for example, a connector (not shown).

  5 and 6 are cross-sectional views taken along line A-A 'of FIG. 3 and cross-sectional views taken along line B-B' of FIG. As shown in FIGS. 5 and 6, the wiring substrate 50 has a laminated structure including a wiring pattern (GND pattern 53, substrate wiring pattern 54 or spreader 59) and insulating layers 55 and 56.

  FIG. 7 is an enlarged view of a portion indicated by a two-dot chain line in FIG. The contact position 57 schematically shows a position where the bump 40 is arranged by a white circle. The contact position 57 on the spreader 59 is disposed at a position corresponding to the bump position 42 shown in FIG. Further, the contact position 57 on the wiring pattern 54 is arranged at a position corresponding to the electrode pad 4 of the solid-state imaging device 1.

  8 and 9 are cross-sectional views illustrating a configuration when the solid-state imaging device 100 illustrated in FIG. 1 is assembled. 8 is a cross-sectional view of the solid-state imaging device 100 shown in FIG. 1 at a position corresponding to A-A ′ shown in FIG. 3. As shown in FIG. 8, metal bumps 40 are arranged on the surface wiring layer 3 and the electrode pads 4 provided in the solid-state imaging device 1. The metal bumps 40 are fixed to the substrate wiring pattern 54 or the spreader 59 with an adhesive 41 while being thermally and electrically connected.

  FIG. 9 is an enlarged view of a portion indicated by a two-dot chain line in FIG. The solid-state imaging device 1 has a multilayer wiring structure including a semiconductor substrate 20, an insulating layer 21, and intermediate wiring layers 22 and 23. The light receiving pixel portion 2 and the signal readout circuits 7 to 11 (the TG circuit 6 is not shown) are formed on the surface of the semiconductor substrate 20. The intermediate wiring contact 29 is provided so as to extend from the signal readout circuits 7 to 11 to the surface wiring layer 3 through the intermediate wiring layers 22 and 23. Here, the insulating layer 21 is made of, for example, silicon dioxide, and the intermediate wiring layers 22 and 23 are made of, for example, a metal such as aluminum or copper, or an alloy, and can be formed by a general semiconductor manufacturing process.

  Hereinafter, the detailed configuration of the heat transfer path of the signal readout circuits 7 to 11 will be described. The intermediate wiring layers 22 and 23 are thermally and electrically connected to the intermediate wiring contact 29, and are connected to the GND potential of the signal readout circuits 7 to 11 in this embodiment. Note that, instead of the GND potential, a common potential supplied to the signal reading circuits 6 to 11 and the like can be used. Further, as the intermediate wiring layers 22 and 23, an appropriate configuration such as a wiring for connecting a plurality of intermediate wiring contacts 29 to each other or a solid GND can be adopted.

The intermediate wiring contact 29 extends from the semiconductor substrate 20 to the intermediate wiring layer 22, the intermediate wiring contact 25 extends from the intermediate wiring layer 22 to the intermediate wiring layer 23, and extends from the intermediate wiring layer 23 to the surface wiring layer 3. An intermediate wiring contact 26 is formed. Each of the intermediate wiring contacts 24 to 26 can be formed by a general semiconductor manufacturing process.
Further, here, the intermediate wiring contacts 24 to 26 are arranged on a straight line, and the signal readout circuits 7 to 11 and the surface wiring layer 3 are connected. However, they may be arranged so as to be separated on the intermediate wiring layers 22 and 23. it can.

As described above, in the solid-state imaging device 100, the signal readout circuits 6 to 11 and the wiring board 50 on the semiconductor substrate 20 are heated by the connection configuration including the intermediate wiring contact 29, the metal bump 40, and the wiring board contact 52. It is the structure which was connected electrically and electrically.
An on-chip microlens 30 and a color filter 28 are provided between the pixel unit 2 and the cap 71 corresponding to the arrangement of the image sensor 2a (see FIG. 2). An airtight space 72 is formed between the cap 71 and a position facing the light receiving pixel portion 2 of the solid-state imaging device 1.

The action of heat radiation from the signal readout circuits 7 to 11 of the solid-state imaging device 100 of the present embodiment configured as described above will be described with reference to FIG. The arrows shown in FIG. 9 schematically show the heat transfer path of the heat generated by the peripheral circuits 6 to 11 of the solid-state imaging device 1.
In the solid-state imaging device 100 of the present embodiment, light enters from the outside of the solid-state imaging device 100 through the cap 71 and reaches the light-receiving pixel 2a of the light-receiving pixel unit 2 through the on-chip microlens 30 and the color filter 28. To do.

  The charge accumulated in the light receiving pixel 2a is output to the outside after predetermined signal processing is performed by each circuit of the signal readout circuits 6-11. Since the signal readout circuits 6 to 11 operate at a high drive frequency, they generate heat.

  Since the intermediate wiring contact 29 made of tungsten and the intermediate wiring layers 22 and 23 made of Al, copper, etc. have higher heat transfer efficiency than the insulating layer 21 made of silicon dioxide, the heat generated by the CDS circuit 7 is, for example, The intermediate wiring layers 22 and 23 are transmitted through the intermediate wiring contact 29 to reach the surface wiring layer 3 and diffused throughout the surface wiring layer 3. Further, the heat diffused in the surface wiring layer 3 reaches the spreader 59 via the metal bumps 40 and is diffused throughout the spreader 59.

  The heat diffused in the spreader 59 is subsequently distributed to each of the wiring board contacts 52, reaches the GND pattern 53 on the surface of the wiring board 50, and is diffused throughout the GND pattern 53. Further, heat is radiated from the surface 53a of the GND pattern 53 to the outside.

  As described above, according to the solid-state imaging device 100 of the present embodiment, the spreader 59 is disposed at a position facing the signal readout circuits 6 to 11 of the solid-state imaging device 1. Further, an intermediate wiring contact 29 for thermally and electrically connecting the signal reading / reading circuits 6 to 11 and the wiring board 50 at a position in a range facing the signal reading circuits 6 to 11 of the solid-state imaging device 1, metal A plurality of bumps 40 and wiring board contacts 52 are arranged. With these configurations, the heat generated by the signal readout circuits 6 to 11 is transmitted to the GND pattern 53 of the wiring board 50 through the connection member having a high heat transfer efficiency, and is radiated from the GND pattern 53 to the outside. Can be improved. In other words, the heat transfer path to the wiring board 50 is the shortest so that heat diffusion inside the solid-state imaging device 1 can be prevented. Further, since the through hole 51 of the wiring board 50 is formed so as to surround the light receiving pixel portion 2, the airtight space 72 is not included in the position where the signal readout circuits 6 to 11 are opposed to each other. The amount of heat can be greatly reduced. Therefore, it is possible to provide a solid-state imaging device that can capture a good image by preventing a high-temperature state of the solid-state imaging element due to heat generation of the signal readout circuit of the solid-state imaging element.

  Moreover, since the intermediate wiring layers 22 and 23 are used as heat transfer paths, the wiring pattern of the intermediate wiring layers 22 and 23 can be changed, and the degree of freedom in setting the heat transfer paths can be increased.

  Further, the intermediate wiring contact 29 and the wiring board contact 52 are formed on the solid-state imaging device 1 and the wiring board 50 by a general manufacturing process. Further, since the other connecting members, the intermediate wiring layers 22 and 23, the surface wiring layer 3, the metal bump 40, the spreader 59, and the GND pattern 53 can be formed by a general manufacturing process, it is necessary to provide an additional process for heat dissipation. The time and cost required for manufacturing the solid-state imaging device 100 can be reduced.

  Further, since the intermediate wiring contact 29, the wiring board contact 52, and the metal bump 40 are connected to the GND pattern 53, the solid-state imaging device 100 can be obtained by sharing the GND potential between the solid-state imaging device 1 and the wiring board 50. Can be stabilized.

  Here, the wiring substrate 50 has been described using a two-layer flexible substrate, but a single-layer or multilayer flexible substrate, a hard substrate typified by FR4, or the like can also be used. Also, other electrical components can be mounted on the wiring board.

  Further, the metal bump 40 and the adhesive 41 have been described. However, the solid-state imaging device 1 such as an anisotropic conductive film and the wiring board 50 may be thermally and electrically connected and fixed. That's fine.

  Further, since a plurality of intermediate layer wiring contacts 29, metal bumps 40, and wiring board contacts 52 are arranged at predetermined intervals with respect to the signal readout circuits 6 to 11, heat is individually applied to each unit circuit of the signal readout circuit. A transmission path can be provided, and the heat generated by the signal readout circuits 6 to 11 is diffused to any one of the connection members arranged at predetermined intervals, and is dispersed by each of the plurality of connection members to the wiring substrate 50. Communicated. As a result, the heat generated by the signal readout circuits 6 to 11 is evenly transmitted, thereby reducing the heat bias in the signal readout circuits 6 to 11 and suppressing the temperature-related performance variation due to the circuit formation position. Can do.

Further, since the surface wiring layer 3 is a light-shielding layer that blocks the incidence of light on the signal readout circuits 6 to 11, unnecessary light is prevented from being mixed into the signal readout circuits 6 to 11. It is possible to prevent malfunction of each circuit.
Note that the signal readout circuits 6 to 11 may be arranged intensively in a circuit that generates a large amount of heat. Thereby, it is possible to further reduce the heat bias of the entire signal readout circuit.
Moreover, although the case where it comprised with the connection member for making a thermal and electrical connection was demonstrated, it is also possible to comprise using the connection member which performs only thermal connection.

(Second Embodiment)
Next, a solid-state imaging device according to a second embodiment of the present invention will be described with reference to FIGS. In the second embodiment, in addition to the configuration shown in the first embodiment in which the signal readout circuit and the wiring board are thermally and electrically connected at a position facing the signal readout circuit of the solid-state imaging device, the signal readout circuit The circuit board is configured to be thermally and electrically connected to the wiring board even at a position that is not opposed to the wiring board. In each embodiment described below, portions having the same configuration as those of the solid-state imaging device 100 of the first embodiment described above are denoted by the same reference numerals and description thereof is omitted.

As shown in FIG. 10, the solid-state imaging device 200 includes a surface wiring layer 203 instead of the surface wiring layer 3 of the solid-state imaging device 1, and the surface wiring layer 203 has bumps protruding toward the peripheral edge side of the solid-state imaging device 200. A position 242 is defined, and this position is schematically indicated by a white circle.
11 and 12 are diagrams showing the front and back surfaces of the wiring board 250 corresponding to each solid-state imaging device 200. FIG. 13 and 14 are CC ′ and DD ′ cross-sectional views shown in FIG. 11, respectively.

  Further, as shown in FIGS. 11 to 14, the wiring board 250 further includes a wiring board contact 252 in addition to the wiring board contact 52, and a spreader 259 connected to the wiring board contact 252 instead of the spreader 59. . Similar to the wiring board contact 52, the wiring board contact 252 of the wiring board 250 is connected to the GND pattern 53 on the front surface of the wiring board 250 and the spreader 259 on the back surface of the wiring board 50.

  Further, the contact position 257 schematically shows a position where the bump 40 is arranged by a white circle. The contact position 257 on the spreader 259 is disposed at a position corresponding to the bump position 242 shown in FIG. 10, and the contact position 257 and the wiring board contact 252 are disposed on the surface of the spreader 259 so as to be separated from each other. .

  FIG. 15 is a cross-sectional view of the solid-state imaging device at a position corresponding to E-E ′ illustrated in FIG. 10. As shown in FIG. 15, the solid-state imaging device 200 of this embodiment includes an intermediate wiring layer 222 instead of the intermediate wiring layer 22 of FIG. 9. The intermediate wiring layers 222 and 23 are thermally and electrically connected to the intermediate wiring contact 29, and are connected to the GND potential of the signal readout circuits 7 to 11 (the TG circuit 6 is not shown). Note that, instead of the GND potential, a common potential supplied to the signal reading circuits 6 to 11 and the like can be used.

  The action of heat radiation from the signal readout circuits 7 to 11 will be described with reference to FIG. An arrow shown in FIG. 15 schematically shows a heat transfer path of heat generated by the peripheral circuits 7 to 11 of the solid-state imaging device 200. Heat generated by the signal readout circuits 7 to 11 is transmitted to the intermediate wiring layers 222 and 23 through the intermediate wiring contact 29, reaches the surface wiring layer 203, and is diffused throughout the surface wiring layer 203. Further, the heat diffused in the surface wiring layer 203 reaches the spreader 259 via the metal bumps 40 and is diffused throughout the spreader 259. The heat diffused in the spreader 259 is then distributed to each of the wiring board contacts 252 and 52, reaches the GND pattern 53 on the surface of the wiring board 50, and is diffused throughout the GND pattern 53. Further, heat is radiated from the surface of the GND pattern 53 to the outside.

  Even in such a configuration, similarly to the first embodiment, it is possible to provide a solid-state imaging device capable of capturing a good image by preventing a high-temperature state of the solid-state imaging device due to heat generation of the signal readout circuit of the solid-state imaging device. .

  Further, since the spreader 259 having a larger area than the spreader 59 and the wiring board contact 252 are further provided, the heat transfer path is increased as compared with the first embodiment, so that the heat radiation efficiency can be further improved.

As mentioned above, although embodiment of this invention was explained in full detail with reference to drawings, the concrete structure is not restricted to this embodiment, The design change etc. of the range which does not deviate from the summary of this invention are included.
For example, as shown in FIG. 16, a heat conductive adhesive 111 is applied to the GND pattern 53, and a heat dissipation plate 112 made of aluminum or the like is further bonded. The heat radiating plate 112 may be configured to be thermally connected to a housing (not shown) on which the solid-state imaging device 110 is mounted to dissipate heat.

  In addition, as shown in FIG. 17, a heat dissipation area can be further increased by adhering heat dissipation fins 122 such as aluminum on a GND pattern via a heat conductive adhesive 121.

  In the embodiment of the present invention, the configuration in which the intermediate wiring layers 22, 23, and 222 are provided between the semiconductor substrate 20 and the wiring substrate 50 has been described in detail as an example. Even if the configuration does not include the intermediate wiring layer, the same effects as those of the present invention can be obtained.

  Here, for the sake of simplicity, the case where the surface wiring layer is provided at a position covering the circuit (signal readout circuits 6 to 11) that operates at a high driving frequency is shown, but the circuit operates at a low driving frequency. Of course, it is possible to cover and cover the region including the circuit (vertical scanning circuit 5). Further, the surface wiring layer can be divided and covered in accordance with the circuit position of each signal readout circuit. Furthermore, the spreader can be divided in the same wiring board, or a plurality of wiring boards provided with the spreader can be used. That is, as long as the signal readout circuit and the wiring board can be thermally and electrically connected at least at a position facing the signal readout circuit of the solid-state imaging device, various modifications and applications within the scope of the present invention are possible. Is possible.

1 is an exploded view showing a configuration of a solid-state imaging device according to a first embodiment of the present invention. It is a figure which shows the structure of the solid-state image sensor of 1st embodiment of this invention. It is a figure which shows the structure of the surface of the wiring board of 1st embodiment of this invention. It is a figure which shows the structure of the back surface of the same wiring board. FIG. 4 is a cross-sectional view taken along line A-A ′ of FIG. 3. FIG. 4 is a cross-sectional view taken along line B-B ′ of FIG. 3. FIG. 5 is a partially enlarged view of the wiring board shown in FIG. 4. It is sectional drawing which shows the structure of the solid-state imaging device corresponding to the A-A 'line of FIG. It is a partially expanded view which shows the structure of the solid-state imaging device. It is a figure which shows the structure of the solid-state image sensor of 2nd embodiment of this invention. It is a figure which shows the structure of the surface of the wiring board of 2nd embodiment of this invention. It is a figure which shows the structure of the back surface of the wiring board of 2nd embodiment of this invention. It is sectional drawing in the C-C 'line of FIG. It is sectional drawing in the D-D 'line | wire of FIG. It is sectional drawing which shows the structure of the solid-state imaging device corresponding to the E-E 'line of FIG. It is sectional drawing which shows the modification of the solid-state imaging device of embodiment of this invention. It is sectional drawing which shows the other modification of the solid-state imaging device of embodiment of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 100,110,120 Solid-state imaging device 1,200 Solid-state image sensor 2 Light receiving pixel part 2a Light receiving pixel 3,203 Surface wiring layer 5, 6, 7, 8, 9, 10, 11 Signal read-out circuit 20 Semiconductor substrate 22, 23 , 222 Intermediate wiring layer 29 Intermediate wiring contact 40, 240 Metal bump 50, 250 Wiring board 51 Through hole 52, 252 Wiring board contact 59, 259 Spreader

Claims (9)

A semiconductor substrate having a signal readout circuit for reading out signals of a plurality of light receiving pixels;
A wiring board having a wiring pattern at a position facing the signal readout circuit;
A solid-state imaging device comprising: a connection member thermally connected to the signal readout circuit and the wiring board at least at the position. The connecting member is
The solid-state imaging device according to claim 1, further comprising an electrical connection function. The solid-state imaging device according to claim 1, wherein a plurality of the connection members are arranged. The solid-state imaging device according to claim 1, wherein a plurality of the connection members are arranged at predetermined intervals with respect to the signal readout circuit. The connecting member is
It has a surface wiring layer disposed on the surface of the semiconductor substrate, and has metal bumps thermally connected to the surface wiring layer and a wiring pattern disposed on the surface of the wiring substrate. The solid-state imaging device according to claim 1. The connecting member is
The semiconductor substrate further includes an intermediate wiring layer and an intermediate wiring contact interposed between the readout circuit and the surface wiring layer inside the semiconductor substrate, and the signal readout circuit, the intermediate wiring layer, and the The solid-state imaging device according to claim 5, wherein the surface wiring layer is connected. The surface wiring layer is
The solid-state imaging device according to claim 5, wherein the solid-state imaging device is disposed so as to cover the signal readout circuit and has a light shielding function. The connecting member is
The solid-state imaging device according to claim 1, further comprising a wiring board contact connected to a wiring pattern of a front surface and a back surface so as to penetrate the wiring board. The wiring board has a through hole formed so as to surround a peripheral portion of the light receiving pixel, and
2. The solid-state imaging device according to claim 1, further comprising a flat-plate cap that is disposed so that one surface of the wiring substrate faces the light receiving pixel and seals the through hole.

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