Imaging device and camera

Abstract

To provide an imaging apparatus and a camera.SOLUTION: An imaging apparatus comprises: an imaging chip having an imaging part that has first pixels outputting first pixel signals generated from photoelectrically converted electric charges and second pixels outputting second pixel signals generated from photoelectrically converted electric charges, a first peripheral part that is formed outside the imaging part, and a second peripheral part that is formed outside the imaging part; a first signal processing chip that is a chip laminated on the imaging chip in the first peripheral part and has a first processing circuit performing signal processing on the first pixel signals output from the first pixels; and a second signal processing chip that is a chip laminated on the imaging chip in the second peripheral part and has a second processing circuit performing signal processing on the second pixel signals output from the second pixels. The first signal processing chip and the second signal processing chip are arranged separated from each other on the inside of the outer edge of the imaging chip.SELECTED DRAWING: None

Description

[Technical field]

[0001] The present invention relates to an imaging device and a camera. [Background technology]

[0002] 2. Description of the Related Art A semiconductor module in which a MOS image sensor chip and a signal processing chip are stacked is known. [Prior art document] [Patent documents] [Patent Document 1] JP 2006-49361 A Summary of the Invention [Problem to be solved by the invention]

[0003] The signal processing chip has a processing circuit that processes pixel signals output from the imaging chip. This processing circuit generates heat during operation. The heat generated by the processing circuit may concentrate in the imaging region of the imaging chip. When this happens, dark current increases in the imaging region due to the heat generated by the processing circuit. As a result, image quality deteriorates. [Means for solving the problem]

[0004] An imaging device in a first aspect of the present invention comprises an imaging section in which a first pixel that outputs a first pixel signal generated from a photoelectrically converted charge and a second pixel that outputs a second pixel signal generated from a photoelectrically converted charge are arranged, an imaging chip having a first peripheral section formed outside the imaging section and a second peripheral section formed outside the imaging section, a first signal processing chip that is stacked on the imaging chip in the first peripheral section and has a first processing circuit that performs signal processing on the first pixel signal output from the first pixel, and a second signal processing chip that is stacked on the imaging chip in the second peripheral section and has a second processing circuit that performs signal processing on the second pixel signal output from the second pixel, wherein the first signal processing chip and the second signal processing chip are arranged apart from each other and inside the outer edge of the imaging chip.

[0005] A camera according to a second aspect of the present invention includes the imaging device described above.

[0006] The above summary of the invention does not list all of the necessary features of the present invention. Also, subcombinations of these features may also be inventions. [Brief description of the drawings]

[0007] [Figure 1] 1 is a schematic perspective view of an imaging device according to an embodiment of the present invention. [Diagram 2] FIG. 2 is a schematic cross-sectional view of an imaging device. [Diagram 3] FIG. 1 is a block diagram showing a configuration of a camera according to an embodiment of the present invention. [Figure 4] FIG. 2 is a schematic cross-sectional view of an imaging device. [Diagram 5] FIG. 2 is a schematic cross-sectional view of an imaging device. [Figure 6] FIG. 2 is a schematic cross-sectional view of an imaging device. [Figure 7] FIG. 2 is a schematic cross-sectional view of an imaging device. [Figure 8] FIG. 2 is a schematic cross-sectional view of an imaging device. [Figure 9] FIG. 2 is a schematic cross-sectional view of an imaging device. [Figure 10] FIG. 2 is a schematic cross-sectional view of an imaging device. [Figure 11] FIG. 2 is a schematic cross-sectional view of an imaging device. [Figure 12] FIG. 2 is a schematic cross-sectional view of an imaging device. [Figure 13] FIG. 2 is a schematic cross-sectional view of an imaging device. [Figure 14] FIG. 2 is a schematic cross-sectional view of an imaging device. [Figure 15] FIG. 2 is a schematic cross-sectional view of an imaging device. [Figure 16] FIG. 2 is a schematic cross-sectional view of an imaging device. [Figure 17] FIG. 2 is a schematic cross-sectional view of an imaging device. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0008] The present invention will be described below through embodiments of the invention, but the following embodiments do not limit the scope of the invention according to the claims. In addition, not all of the combinations of features described in the embodiments are necessarily essential to the solution of the invention.

[0009] FIG. 1 is a schematic perspective view of an imaging device of this embodiment. The imaging device 100 includes an imaging chip 101, a cover glass 111 as an optical element, a signal processing chip 121, and a flexible substrate 141. In FIG. 1, bumps between the imaging chip 101 and the signal processing chip 121, and bumps between the signal processing chip 121 and the flexible substrate 141 are omitted for the purpose of simplifying the drawing. Also, the same hatching as in FIG. 2 is used to make an adhesive layer 131, which will be described later, easier to see. In FIG. 1, the direction in which a subject light flux enters the imaging chip 101 is the z-axis direction. The longitudinal direction of the imaging chip 101 is the x-axis direction, and the lateral direction is the y-axis direction. The positive x-axis direction is the right direction on the paper, and the negative x-axis direction is the left direction on the paper.

[0010] The imaging chip 101 has an imaging region on a first surface side, which is a surface on which a subject light beam is incident. In this specification, an area facing the imaging region on a second surface, which is a surface opposite to the light receiving surface of the imaging chip 101, is referred to as an opposing area 110.

[0011] The signal processing chip 121 is stacked on the second surface side of the imaging chip 101. The signal processing chip 121 has a processing circuit that processes pixel signals output from the imaging chip 101. The imaging chip 101 and the signal processing chip 121 have different sizes. Here, the width of the signal processing chip 121 in the y-axis direction is approximately the same as the width of the imaging chip 101 in the y-axis direction. On the other hand, the width of the signal processing chip 121 in the x-axis direction is approximately 1 / 3 the width of the imaging chip 101 in the x-axis direction.

[0012] The number of signal processing chips is appropriately determined according to the pixel signal readout method. In this embodiment, a two-channel readout method is adopted as the pixel signal readout method. Therefore, in this embodiment, the number of signal processing chips is two. One of the two signal processing chips 121 is arranged along the left end of the imaging chip 101, and the other is arranged along the right end of the imaging chip 101. The two signal processing chips 121 are arranged without protruding from the outer edge of the second surface of the imaging chip 101 in the x-axis direction and the y-axis direction. This allows the imaging device 100 to be miniaturized in the x-axis direction and the y-axis direction.

[0013] The two signal processing chips 121 are arranged at an interval from each other in the x-axis direction. Therefore, each of the two signal processing chips 121 only covers a part of the facing region 110. In other words, the facing region 110 has a part that is not covered by the signal processing chip 121.

[0014] Here, if the entire facing region 110 is covered by the signal processing chip 121, heat generated by the processing circuit may concentrate in the imaging region. When heat concentrates in the imaging region, dark current caused by the heat increases. As a result, image quality is degraded.

[0015] According to the imaging device 100 of this embodiment, the two signal processing chips 121 are arranged near both the left and right ends of the imaging chip 101, avoiding the center portion of the facing region 110. That is, a space is formed between the two signal processing chips 121. According to this configuration, a part of the heat generated in the processing circuit of the signal processing chip 121 can be dissipated to the space. Therefore, it is possible to reduce the accumulation of heat in the imaging region. As a result, it is possible to reduce the dark current generated due to heat in the imaging region.

[0016] The signal processing chip 121 is connected to a flexible substrate 141 as a substrate having flexibility. The flexible substrate 141 is connected to an external circuit. The flexible substrate 141 is connected to a surface of the signal processing chip 121 opposite to a third surface which is a surface on the imaging chip 101 side.

[0017] The adhesive layer 131 is formed on the outer edge of the surface of the imaging chip 101 on which the subject light beam is incident. The adhesive layer 131 is formed so as to surround the imaging region. The adhesive layer 131 bonds the imaging chip 101 and the cover glass 111 together.

[0018] 2 is a schematic cross-sectional view of the imaging device, specifically, a schematic cross-sectional view of the xz plane passing through the center of the imaging chip 101.

[0019] The imaging chip 101 is a front-illuminated MOS image sensor. The imaging chip 101 has a circuit pattern 103, a through electrode 104, and an electrode pad 105 in addition to the imaging region 102 described above.

[0020] The imaging region 102 is formed in the center of the imaging chip 101. In the imaging region 102, a plurality of pixels are arranged to perform photoelectric conversion on a received subject image.

[0021] The circuit pattern 103, the through electrodes 104, and the electrode pads 105 are formed in a peripheral region shifted to the right and to the left from the outer edge of the imaging region 102, respectively. The electrode pads 105 are formed on a second surface of the imaging chip 101. The circuit pattern 103 and the electrode pads 105 are electrically connected via the through electrodes 104. The circuit pattern 103 outputs pixel signals read out from the pixels to the through electrodes 104. The through electrodes 104 output pixel signals output from the circuit pattern 103 to the electrode pads 105. The electrode pads 105 function as an output unit that outputs pixel signals to an electrode pad 125, which will be described later.

[0022] The signal processing chip 121 has a through electrode 124, an electrode pad 125, and an electrode pad 126 in addition to the above-mentioned processing circuit. The electrode pad 125 is formed on a third surface of the signal processing chip 121. On the other hand, the electrode pad 126 is formed on a surface of the signal processing chip 121 facing the flexible substrate 141. The electrode pad 125 and the electrode pad 126 are electrically connected via the through electrode 124. The through electrode 124 outputs a pixel signal processed by the processing circuit to the flexible substrate 141.

[0023] The electrode pads 125 of the signal processing chip 121 are electrically connected to the electrode pads 105 of the imaging chip 101 via bumps 132. The electrode pads 125 function as an input section that inputs pixel signals output from an output section. Note that the bumps 132 interposed between the electrode pads 105 and 125 can also be regarded as an output section or an input section. The imaging chip 101 and the signal processing chip 121 are bonded with an adhesive 133.

[0024] The flexible substrate 141 has electrode pads 144. The electrode pads 144 are electrically connected to the electrode pads 126 of the signal processing chip 121 via bumps 134. The connection portions of the electrode pads 144 and the electrode pads 126 are bonded with an adhesive 135. The flexible substrate 141 outputs pixel signals received via the through electrodes 124 of the signal processing chip 121 to an external circuit.

[0025] The cover glass 111 is made of borosilicate glass, quartz glass, alkali-free glass, heat-resistant glass, or the like. The cover glass 111 is disposed on the adhesive layer 131 facing the imaging region 102, and is adhered to the imaging chip 101 via the adhesive layer 131. The adhesive layer 131 is interposed between the imaging chip 101 and the cover glass 111, and is formed so as to surround the imaging region 102. A thermosetting adhesive or the like can be used as a material for the adhesive layer 131. The cover glass 111 seals the imaging region 102 while being separated from the imaging chip 101 by the thickness of the adhesive layer 131.

[0026] 3 is a block diagram showing the configuration of a camera according to this embodiment. The camera 150 includes a photographing lens 420 as a photographing optical system, which guides a subject light beam incident along an optical axis OA to the image capturing device 100. The photographing lens 420 may be an interchangeable lens that can be attached to and detached from the camera 150. The camera 150 mainly includes the image capturing device 100, a system control unit 401, a work memory 404, a recording unit 405, and a display unit 406.

[0027] The photographing lens 420 is composed of a group of optical lenses, and focuses the subject light from the scene near its focal plane. Note that in Fig. 3, it is represented by a virtual single lens arranged near the pupil. The system control unit 401 executes charge accumulation control such as timing control and area control of the image pickup device 100.

[0028] The imaging device 100 passes the pixel signal to an image processing unit 411 in the system control unit 401. The image processing unit 411 performs various image processes using the work memory 404 as a workspace to generate image data. For example, when generating image data in a JPEG file format, compression processing is performed after white balance processing, gamma processing, etc. are performed. The generated image data is recorded in a recording unit 405, and is also converted into a display signal and displayed on a display unit 406.

[0029] In the above description, the imaging device 100 is configured to include the flexible substrate 141 as a connection member to an external circuit, but may include other connection members. Fig. 4 is a schematic cross-sectional view of the imaging device of the first modification.

[0030] The imaging device 200 includes a wiring board 151 that is a rigid board instead of a flexible board. The imaging device 200 outputs pixel signals to an external circuit via the wiring board 151. A ceramic board, a glass epoxy board, or the like can be used as the wiring board 151. In the imaging device 200, the through electrodes 124 of the signal processing chip 121 output pixel signals processed by the processing circuit to the wiring board 151. The wiring board 151 has electrode pads 152. The electrode pads 152 are electrically connected to the electrode pads 126 of the signal processing chip 121 via the bumps 134. The wiring board 151 is fixed to the surface of the signal processing chip 121 opposite to the third surface via an adhesive 135. In this manner, the wiring board 151 is disposed adjacent to the signal processing chip 121 and is electrically connected thereto.

[0031] The configuration using the wiring board 151 as a connection member with an external circuit is not limited to the configuration shown in FIG. 4. FIG. 5 is a schematic cross-sectional view of an imaging device of Modification 2. The imaging device 300 includes a surrounding member 161 having a rectangular ring shape. The surrounding member 161 is disposed on the wiring board 151 to surround the imaging chip 101. The surrounding member 161 is formed of a metal such as aluminum, brass, iron, or nickel alloy. The surrounding member 161 may be made of a resin, or may be made of a material obtained by insert molding of a metal and a resin. As will be described in detail later, when emphasis is placed on improving the sealing performance of the imaging device 300, it is preferable to use a metal as the material of the surrounding member 161. The cover glass 111 is disposed on the surrounding member 161 and is bonded by an adhesive layer 131.

[0032] If dust, foreign matter, etc. adhere to the cover glass 111 or if the cover glass 111 is scratched, these may appear in the captured image. By interposing the surrounding member 161 between the wiring board 151 and the cover glass 111 and widening the gap between the imaging chip 101 and the cover glass 111, the effect of the reflection can be reduced. In addition, stray light due to reflection at the end face of the cover glass 111 is less likely to reach the imaging region 102. While the use of the surrounding member 161 can widen the gap between the imaging chip 101 and the cover glass 111, the thickness of the imaging device 300 in the z-axis direction becomes thicker than when the surrounding member 161 is not used. The thickness of the surrounding member 161 is appropriately adjusted from the viewpoints of reducing the reflection and miniaturizing the imaging device 100.

[0033] A sealed space is formed by the cover glass 111, the wiring board 151, and the surrounding member 161. The imaging chip 101 is disposed in the sealed space. Here, when moisture and gas from the external environment enter the inside of the imaging device 300, the imaging performance of the imaging chip 101 is reduced. Specifically, when moisture from the external environment enters the sealed space, condensation occurs on the imaging chip 101 and the cover glass 111 due to the temperature difference between the inside and outside of the sealed space. When condensation and mold occur due to condensation, the optical image formed is distorted, and noise increases. On the other hand, when gas from the external environment enters the sealed space, oxidation and corrosion of the circuit inside the imaging chip 101 are promoted, leading to destruction of the imaging chip 101. By disposing the imaging chip 101 in the sealed space, the imaging chip 101 is less susceptible to the influence of moisture and gas from the external environment, so that an increase in noise can be suppressed and destruction of the imaging chip 101 can be avoided.

[0034] Another configuration in which a wiring board 151 is used as a connection member to an external circuit will be described below.

[0035] The imaging device 400 includes an electrode pad 106 on the surface of the imaging chip 101. The electrode pad 106 is electrically connected to an electrode pad 105 via a through electrode 104. The wiring board 151 includes an electrode pad 152. The electrode pad 152 is electrically connected to the electrode pad 106 via a wire bonding 171.

[0036] According to the configuration of the imaging device 400, pixel signals read out from pixels are temporarily output to the signal processing chip 121 via the through electrodes 104. The pixel signals are processed by a processing circuit of the signal processing chip 121 and then output again to the imaging chip 101. Then, the pixel signals are output to the wiring board 151 via the wire bonding 171.

[0037] In the imaging device 200 shown in Fig. 4 and the imaging device 300 shown in Fig. 5, the signal processing chip 121 is configured to be electrically connected to the wiring board 151. For this reason, the signal processing chip 121 is provided with the through electrodes 124 for outputting pixel signals to the wiring board 151. In contrast, according to the configuration of the imaging device 400, the signal processing chip 121 does not include the through electrodes 124, which is advantageous in terms of the manufacturing process and manufacturing costs.

[0038] The configuration in which no through electrodes are formed in the signal processing chip 121 is not limited to the configuration shown in Fig. 6. Fig. 7 is a schematic cross-sectional view of an imaging device according to the fourth modification.

[0039] The wiring board 151 of the imaging device 500 has a convex land portion 153 that protrudes toward a region (i.e., a facing region) facing the imaging region 102 on the second surface. The land portion 153 is formed in the center of the wiring board 151, avoiding the region where the signal processing chip 121 is arranged. The land portion 153 functions as a heat dissipation member that dissipates heat generated in the imaging chip 101. In other words, the land portion 153 can be said to be a heat dissipation member that abuts against the facing region. In this way, in the imaging device 500, a heat dissipation member is arranged in the space between the two signal processing chips 121. When heat dissipation characteristics are important, the larger the bonding surface between the land portion 153 and the imaging chip 101, the better.

[0040] On the other hand, the linear expansion coefficient of imaging chip 101 and the linear expansion coefficient of wiring board 151 are different from each other. For this reason, when imaging chip 101 and wiring board 151 are heated or cooled after being bonded together, they warp. This is because the amount of expansion or contraction due to heating or cooling differs between imaging chip 101 and wiring board 151. If prevention of warping is important, the smaller the bonding surface between land section 153 and imaging chip 101, the better.

[0041] The wiring board 151 is fixed to the imaging chip 101 by the adhesive 136 via the land portion 153. An elastic adhesive may be used as the adhesive 136. The elastic adhesive may be an acrylic resin, a silicone resin, an epoxy resin, or the like. By using an elastic adhesive as the adhesive 136, it is possible to absorb stress caused by the difference in linear expansion coefficient between the imaging chip 101 and the wiring board 151 when the imaging chip 101 and the wiring board 151 are heated or cooled after being joined together.

[0042] The wiring board 151 and the signal processing chip 121 are in contact with each other via a heat dissipation medium 137. The heat dissipation medium 137 is, for example, silicone grease. The wiring board 151 and the signal processing chip 121 are thermally coupled by the heat dissipation medium 137. This allows heat generated in the processing circuit of the signal processing chip 121 to be dissipated to the wiring board 151. This makes it possible to reduce the heat dissipated from the processing circuit to the imaging chip 101 side.

[0043] 8 is a schematic cross-sectional view of an imaging device of Modification 5. A wiring board 151 of the imaging device 600 has an opening 155 corresponding to the imaging region 102, and is fixed to the light receiving surface side of the imaging chip 101. A cover glass 111 covers the opening 155 and is adhered to the wiring board 151 by an adhesive layer 131.

[0044] The wiring board 151 has electrode pads 154. The electrode pads 154 are electrically connected to the electrode pads 106 of the imaging chip 101 via bumps 138. The connection portions of the electrode pads 154 and the electrode pads 106 are bonded with an adhesive 139. The adhesive 139 is formed so as to surround the imaging region 102.

[0045] 4 to 7, the wiring board 151 is disposed on the surface opposite to the third surface of the signal processing chip 121. In contrast, according to the configuration of the imaging device 600, the wiring board 151 is disposed on the light receiving surface side of the imaging chip 101. Therefore, the distance between the imaging chip 101 and the cover glass 111 can be increased compared to the case where the cover glass 111 is disposed on the imaging chip 101 without using the above-mentioned surrounding member.

[0046] In the above description, the two signal processing chips 121 are arranged so as not to protrude from the outer edge of the imaging chip 101 in the x-axis direction and y-axis direction, but they may be arranged so as to protrude from the outer edge of the imaging chip 101. FIG. 9 is a schematic cross-sectional view of an imaging device of the sixth modification.

[0047] The signal processing chip 121 of the imaging device 700 has an electrode pad 127 on the third surface. The electrode pad 127 is formed on a portion of the signal processing chip 121 that protrudes from the outer edge of the imaging chip 101 in the x-axis direction. With this configuration, the electrode pad 127 can be formed on the third surface. Therefore, it is not necessary to form an electrode pad on the surface opposite to the third surface and to take the trouble of forming a through electrode for electrically connecting the electrode pad to the electrode pad. The electrode pad 127 is electrically connected to the electrode pad 145 of the flexible substrate 141 via the bump 140. The connection portion between the electrode pad 127 and the electrode pad 145 is bonded by an adhesive 135.

[0048] By disposing the signal processing chip 121 so that it protrudes from the outer edge of the imaging chip 101 in the x-axis direction, it can be stacked on the imaging chip 101 while completely avoiding the opposing region. This makes it even more difficult for heat generated in the processing circuit to be dissipated to the imaging region 102.

[0049] The above-mentioned various configurations can be adopted even when the two signal processing chips 121 are arranged protruding from the outer edge of the imaging chip 101 in the x-axis direction. FIG. 10 is a schematic cross-sectional view of an imaging device of Modification 7. The imaging device 800 includes a wiring board 151 and a surrounding member 161 as connection members in addition to the imaging chip 101, the signal processing chip 121, and the cover glass 111. The electrode pads 127 of the signal processing chip 121 are electrically connected to the electrode pads 152 of the wiring board 151 via wire bonding 171. Therefore, according to this configuration, the pixel signals output to the signal processing chip 121 can be output to the wiring board 151 without being output again to the imaging chip 101. In addition, as described above, the surrounding member 161 makes the imaging chip 101 less susceptible to the effects of moisture and gas in the external environment, so that an increase in noise can be suppressed and damage to the imaging chip 101 can be avoided.

[0050] FIG. 11 is a schematic cross-sectional view of an imaging device of the eighth modification. The wiring board 151 of the imaging device 900 includes a convex land portion 153 that protrudes toward the facing region. The wiring board 151 is fixed to the imaging chip 101 by the adhesive 136 via the land portion 153. This allows heat generated in the imaging chip 101 to be released. In this manner, in the imaging device 900, a heat dissipation member is disposed in the space between the two signal processing chips 121. In addition, by using an elastic adhesive as the adhesive 136, it is possible to absorb stress caused by the difference in linear expansion coefficient between the imaging chip 101 and the wiring board 151. The wiring board 151 and the signal processing chip 121 are in contact with each other via a heat dissipation medium 137. This allows heat generated in the processing circuit of the signal processing chip 121 to be released to the wiring board 151.

[0051] 12 is a schematic cross-sectional view of an imaging device. A wiring board 151 of the imaging device 1000 has an opening 155 corresponding to the imaging chip 101. The imaging chip 101 is accommodated in the opening 155 of the wiring board 151. The wiring board 151 is fixed to a third surface of the signal processing chip 121. An electrode pad 127 of the signal processing chip 121 is electrically connected to an electrode pad 156 of the wiring board 151 via a bump 140. The connection portion between the electrode pad 127 and the electrode pad 156 is bonded with an adhesive 135.

[0052] 13 is a schematic cross-sectional view of the imaging device. The signal processing chip 121 on the left side of the imaging device 1100 is disposed so as to intrude from the left end of the imaging chip 101 in the positive x-axis direction. On the other hand, the signal processing chip 121 on the right side is disposed so as to intrude from the right end of the imaging chip 101 in the negative x-axis direction. The flexible substrate 141 is disposed in a space created by displacing the signal processing chip 121 from the end of the imaging chip 101. In this way, the flexible substrate 141 may be electrically connected to the imaging chip 101 instead of the signal processing chip 121. The configuration of the imaging device 1100 allows it to be made smaller in the x-axis direction than the imaging device 700 shown in FIG. 9.

[0053] 14 is a schematic cross-sectional view of an imaging device. Land portion 153 of wiring board 151 of imaging device 1200 is formed on the outer edge portion of wiring board 151. Wiring board 151 has electrode pad 157 on land portion 153. Electrode pad 157 is electrically connected to electrode pad 107 of imaging chip 101 via bump 140. In this manner, land portion 153 of wiring board 151 may be formed in a portion other than the central portion of wiring board 151.

[0054] 15 is a schematic cross-sectional view of an imaging device. A wiring board 151 of an imaging device 1300 has an opening 155 corresponding to the signal processing chip 121. The signal processing chip 121 is accommodated in the opening 155 of the wiring board 151. An electrode pad 157 of the wiring board 151 is electrically connected to an electrode pad 107 of the imaging chip 101 via a bump 140. When the wiring board 151 and the imaging chip 101 are electrically connected by bump bonding in this manner, the wiring board 151 can also be disposed on the surface of the imaging chip 101 opposite to the light receiving surface.

[0055] In the above description, the land portion 153 of the wiring board 151 functioning as a heat dissipation member is bonded to the imaging chip 101. The heat dissipation member may be bonded to the signal processing chip 121. FIG. 16 is a schematic cross-sectional view of an imaging device. The imaging device 1400 has a heat dissipation member 181. The heat dissipation member 181 is in contact with the signal processing chip 121 via the heat dissipation medium 137. This allows the heat generated in the signal processing chip 121 to be dissipated via the heat dissipation member 181. This makes it possible to reduce the heat dissipated to the imaging chip 101 side. As a result, it is possible to reduce the dark current generated by the heat generated in the signal processing chip 121. It is preferable that the heat dissipation member 181 is fin-shaped. This increases the heat dissipation area of ​​the heat dissipation member 181, thereby improving the heat dissipation characteristics.

[0056] 17 is a schematic cross-sectional view of an imaging device. Flexible substrate 141 of imaging device 1500 is sandwiched between imaging chip 101 and signal processing chip 121. Bump 134 and bump 132 have different thicknesses. Specifically, bump 132 is thicker than bump 134 by the thickness of flexible substrate 141. By adjusting the thickness of the bumps in this way, a structure in which flexible substrate 141 is sandwiched between imaging chip 101 and signal processing chip 121 can be realized.

[0057] The imaging chip 101 may be a back-illuminated MOS image sensor. In this case, in the imaging chip 101, a plurality of pixels are arranged on the subject image incident side of a wiring layer including wiring that outputs pixel signals to the through electrodes. In the case of the back-illuminated imaging chip 101, the imaging chip is polished, so that the thickness is thinner than that of a front-illuminated imaging chip. For this reason, a support substrate may be attached to the surface of the imaging chip opposite to the light receiving surface, and then the signal processing chip may be arranged on the support substrate. In this case, it is preferable to form a through electrode in the support substrate. This allows the imaging chip and the signal processing chip to be electrically connected via the through electrode of the support substrate.

[0058] The pixel signals of the imaging chip 101 may be transmitted to the signal processing chip 121 by wireless communication using electromagnetic coupling. In this case, the imaging chip 101 and the signal processing chip 121 each have coils formed to face each other.

[0059] In the above description, the land portion 153 of the wiring board 151 functions as a heat dissipation member that dissipates heat generated in the imaging chip 101, but the wiring board 151 and the heat dissipation member do not have to be formed integrally. Also, the imaging chip 101 and the signal processing chip 121 may each have a heat dissipation member provided separately.

[0060] In the above description, the number of signal processing chips 121 is two, but it may be one. Also, the number of signal processing chips 121 may be three or more. In the above description, the cover glass 111 is used as an optical element, but a low-pass filter, an IR cut filter, or the like may be used instead of the cover glass 111.

[0061] Although the present invention has been described above using the embodiments, the technical scope of the present invention is not limited to the scope described in the above embodiments. It is clear to those skilled in the art that various modifications and improvements can be made to the above embodiments. It is clear from the description of the claims that such modifications and improvements can also be included in the technical scope of the present invention. [Explanation of symbols]

[0062] 100 imaging device, 200 imaging device, 300 imaging device, 400 imaging device, 500 imaging device, 600 imaging device, 700 imaging device, 800 imaging device, 900 imaging device, 1000 imaging device, 1100 imaging device, 1200 imaging device, 1300 imaging device, 1400 imaging device, 1500 imaging device, 101 imaging chip, 102 imaging area, 103 circuit pattern, 104 through electrode, 105 electrode pad, 106 electrode pad, 107 electrode pad, 110 facing area, 111 cover glass, 121 signal processing chip, 124 through electrode, 125 electrode pad, 126 electrode pad, 127 electrode pad, 131 adhesive layer, 132 bump, 133 adhesive, 134 bump, 135 Adhesive, 136 Adhesive, 137 Heat dissipation medium, 138 Bump, 139 Adhesive, 140 Bump, 141 Flexible substrate, 144 Electrode pad, 145 Electrode pad, 150 Camera, 151 Wiring substrate, 152 Electrode pad, 153 Land portion, 154 Electrode pad, 155 Opening, 156 Electrode pad, 157 Electrode pad, 161 Surrounding member, 171 Wire bonding, 181 Heat dissipation member, 401 System control unit, 404 Work memory, 405 Recording unit, 406 Display unit, 411 Image processing unit, 420 Taking lens

Claims

1. an imaging chip including: an imaging section including a rectangular imaging region in which a first pixel that outputs a first pixel signal generated by a photoelectrically converted charge and a second pixel that outputs a second pixel signal generated by a photoelectrically converted charge are disposed; a first peripheral section formed outside the imaging section; a second peripheral section formed outside the imaging section; and a wiring layer including wiring through which the first pixel signal is output and wiring through which the second pixel signal is output; a first signal processing chip, which is a rectangular chip stacked on the imaging chip in the first peripheral portion and has a first processing circuit that performs signal processing on the first pixel signal output from the first pixel; a second signal processing chip, which is a rectangular chip stacked on the imaging chip in the second peripheral portion and has a second processing circuit that performs signal processing on the second pixel signal output from the second pixel; Equipped with the imaging chip has a first surface onto which light is incident and a second surface opposite to the first surface; the first pixel and the second pixel are disposed on the first surface side of the wiring layer, a long side of the first signal processing chip is longer than a short side of the imaging area; a long side of the second signal processing chip is longer than a short side of the imaging area; the first signal processing chip and the second signal processing chip are disposed apart from each other on the inner side of an outer edge of the imaging chip. Imaging device.

2. In the imaging device according to claim 1, the imaging chip has a rectangular shape including a first side and a second side opposite to the first side, the first signal processing chip is disposed in the first peripheral portion so as to cover an area from the first side to the second side; the second signal processing chip is disposed so as to cover a region of the second peripheral portion from the first side to the second side; Imaging device.

3. In the imaging device according to claim 2, a length of a long side of the first signal processing chip is equal to a length from the first side to the second side; The length of the long side of the second signal processing chip is equal to the length from the first side to the second side. Imaging device.

4. In the imaging device according to any one of claims 1 to 3, The imaging section is an imaging device disposed between the first peripheral section and the second peripheral section in the imaging chip.

5. In the imaging device according to any one of claims 1 to 3, The imaging device, wherein the imaging section is disposed so as to be sandwiched between the first peripheral section and the second peripheral section in the imaging chip.

6. 6. The imaging device according to claim 1, The imaging chip includes: a first electrode pad to which the first pixel signal that has been subjected to signal processing by the first processing circuit is output; a second electrode pad to which the second pixel signal processed by the second processing circuit is output; An imaging device having the above configuration.

7. 7. The imaging device according to claim 6, a wiring substrate having a first wiring through which the first pixel signal is output from the first electrode pad and a second wiring through which the second pixel signal is output from the second electrode pad; a surrounding member disposed on the wiring board so as to surround the imaging chip; a cover glass fixed to the surrounding member; Equipped with The wiring board, the surrounding member, and the cover glass form a storage space for storing the imaging chip, the first signal processing chip, and the second signal processing chip.

8. 8. The imaging device according to claim 7, The surrounding member is made of metal.

9. 8. The imaging device according to claim 7, The surrounding member is made of resin.

10. 8. The imaging device according to claim 7, The surrounding member is an imaging device made of metal and resin.

11. The imaging device according to any one of claims 7 to 10, a first connection portion that connects the first electrode pad and the first wiring; a second connection portion that connects the second electrode pad and the second wiring; Equipped with The first connection portion and the second connection portion are an imaging device that is stored in the storage space.

12. 12. The imaging device according to claim 11, the first connection portion has a first wire that electrically connects the first electrode pad and the first wiring; The second connection portion includes a second wire that electrically connects the second electrode pad and the second wiring.

13. 12. The imaging device according to claim 11, the first connection portion has a first bump that electrically connects the first electrode pad and the first wiring; The second connection portion has a second bump that electrically connects the second electrode pad and the second wiring.

14. The imaging device according to any one of claims 7 to 13, The cover glass is fixed to the surrounding member by an adhesive.

15. 15. The imaging device according to claim 1, The first signal processing chip is an imaging device having a chip size smaller than that of the imaging chip.

16. 16. The imaging device according to claim 1, The second signal processing chip is an imaging device having a chip size smaller than that of the imaging chip.

17. 17. The imaging device according to claim 1, the imaging chip and the first signal processing chip are electrically connected by a first through electrode, The imaging chip and the second signal processing chip are electrically connected to each other by a second through electrode.

18. 18. The imaging device according to claim 17, An imaging device in which a distance between the first signal processing chip and the second signal processing chip is shorter than a distance between the first through-electrode and the second through-electrode.

19. 17. The imaging device according to claim 1, the imaging chip and the first signal processing chip are electrically connected by a first coil; The imaging chip and the second signal processing chip are electrically connected by a second coil.

20. A camera comprising the imaging device according to any one of claims 1 to 19.

21. 21. The camera according to claim 20, A camera comprising an image processing unit that performs image processing on the first pixel signal that has been subjected to signal processing in the first processing circuit and the second pixel signal that has been subjected to signal processing in the second processing circuit.

Images