Imaging device and camera

Abstract

This invention provides a semiconductor module in which a MOS image sensor chip and a signal processing chip are stacked to prevent image quality degradation caused by heat. [Solution] The imaging device comprises an imaging unit having 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; an imaging chip having a first peripheral portion formed outside the imaging unit and a second peripheral portion formed outside the imaging unit; a first signal processing chip stacked on the imaging chip in the first peripheral portion and having a first processing circuit that performs signal processing on the first pixel signal output from the first pixel; and a second signal processing chip stacked on the imaging chip in the second peripheral portion and having 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 separately from each other inside the outer edge of the imaging chip.

Description

Technical Field

[0005] , , , , ,

[0004]

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

Background Art

[0002] A semiconductor module in which a MOS image sensor chip and a signal processing chip are stacked is known. [Prior Art Document] [Patent Document] [Patent Document 1] Japanese Patent Application Laid-Open No. 2006-49361

Summary of the Invention

Problems 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 in the processing circuit may concentrate in the imaging area of the imaging chip. Then, in the imaging area, the dark current increases due to the heat generated in the processing circuit. As a result, the image quality deteriorates.

Means for Solving the Problems

[0006] It should be noted that the above summary of the invention does not enumerate all the necessary features of the present invention. Furthermore, subcombinations of these features may also constitute an invention. [Brief explanation of the drawing]

[0007] [Figure 1] This is a schematic perspective view of the imaging device of this embodiment. [Figure 2] This is a schematic cross-sectional view of the imaging device. [Figure 3] This is a block diagram showing the camera configuration of this embodiment. [Figure 4] This is a schematic cross-sectional view of the imaging device. [Figure 5] This is a schematic cross-sectional view of the imaging device. [Figure 6] This is a schematic cross-sectional view of the imaging device. [Figure 7] This is a schematic cross-sectional view of the imaging device. [Figure 8] This is a schematic cross-sectional view of the imaging device. [Figure 9] This is a schematic cross-sectional view of the imaging device. [Figure 10] This is a schematic cross-sectional view of the imaging device. [Figure 11] This is a schematic cross-sectional view of the imaging device. [Figure 12] This is a schematic cross-sectional view of the imaging device. [Figure 13] This is a schematic cross-sectional view of the imaging device. [Figure 14] This is a schematic cross-sectional view of the imaging device. [Figure 15] This is a schematic cross-sectional view of the imaging device. [Figure 16] This is a schematic cross-sectional view of the imaging device. [Figure 17] This is a schematic cross-sectional view of the imaging device. [Modes for carrying out the invention]

[0008] The present invention will be described below through embodiments, but these embodiments are not intended to limit the scope of the claims. Furthermore, not all combinations of features described in the embodiments are necessarily essential to the solution of the invention.

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

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

[0011] The signal processing chip 121 is stacked on the second side of the imaging chip 101. The signal processing chip 121 has a processing circuit that processes the pixel signals output from the imaging chip 101. The imaging chip 101 and the signal processing chip 121 are of 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 about one-third of 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, two-channel readout 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 in the x-axis direction and the y-axis direction from the outer edge of the second surface of the imaging chip 101. Thereby, the imaging device 100 can be miniaturized in the x-axis direction and the y-axis direction.

[0013] The two signal processing chips 121 are arranged at intervals in the x-axis direction. Therefore, both of the two signal processing chips 121 only cover a part of the opposing region 110. In other words, the opposing region 110 has a portion that is not covered by the signal processing chip 121.

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

[0015] According to the imaging device 100 of this embodiment, the two signal processing chips 121 are arranged close to both the left and right ends of the imaging chip 101 while avoiding the central portion of the opposing region 110. That is, a space is formed between the two signal processing chips 121. According to this configuration, part of the heat generated in the processing circuit of the signal processing chip 121 can be radiated to the space. Therefore, the retention of heat in the imaging region can be reduced. As a result, in the imaging region, the dark current generated due to heat can be reduced.

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

[0017] The adhesive layer 131 is formed on the outer edge of the surface of the imaging chip 101 to which the subject light beam is incident. The adhesive layer 131 is formed to surround the imaging area. The adhesive layer 131 adheres the imaging chip 101 to the cover glass 111.

[0018] Figure 2 is a schematic cross-sectional view of the imaging device. Specifically, it is 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 surface-illuminated MOS image sensor. In addition to the imaging area 102 described above, the imaging chip 101 has a circuit pattern 103, a through electrode 104, and an electrode pad 105.

[0020] The imaging area 102 is formed in the central part of the imaging chip 101. Multiple pixels that convert the received subject image into photoelectric energy are arranged in the imaging area 102.

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

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

[0023] The electrode pad 125 of the signal processing chip 121 is electrically connected to the electrode pad 105 of the imaging chip 101 via a bump 132. The electrode pad 125 functions as an input unit that receives the pixel signal output from the output unit. The bump 132 interposed between the electrode pad 105 and the electrode pad 125 can also be considered as an output unit or an input unit. The imaging chip 101 and the signal processing chip 121 are bonded together by 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 between electrode pads 144 and electrode pads 126 is bonded by adhesive 135. The flexible substrate 141 outputs the 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, etc. The cover glass 111 is placed on the adhesive layer 131 facing the imaging area 102 and is bonded 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 to surround the imaging area 102. A thermosetting adhesive or the like can be used as the material for the adhesive layer 131. The cover glass 111 seals the imaging area 102 while separating from the imaging chip 101 due to the thickness of the adhesive layer 131.

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

[0027] The imaging lens 420 is composed of multiple optical lens groups and forms an image of the subject light beam from the scene near its focal plane. In Figure 3, it is represented by a single virtual lens positioned near the pupil. The system control unit 401 performs charge accumulation control such as timing control and area control of the imaging device 100.

[0028] The imaging device 100 passes pixel signals to the image processing unit 411 of the system control unit 401. The image processing unit 411 uses the work memory 404 as a workspace to perform various image processing operations and generate image data. For example, when generating image data in JPEG file format, it performs white balance processing, gamma processing, etc., followed by compression processing. The generated image data is recorded in the recording unit 405 and converted into a display signal and displayed in the display unit 406.

[0029] In the above description, the imaging device 100 was configured to include a flexible substrate 141 as a connecting member to an external circuit, but it may also be configured to include other connecting members. Figure 4 is a schematic cross-sectional view of the imaging device of Modification 1.

[0030] The imaging device 200 includes a wiring board 151, which is a rigid substrate, instead of a flexible substrate. The imaging device 200 outputs pixel signals to an external circuit via the wiring board 151. A ceramic substrate, a glass epoxy substrate, or the like can be used as the wiring board 151. In the imaging device 200, the through-electrode 124 of the signal processing chip 121 outputs the 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 bumps 134. The wiring board 151 is fixed to the side of the signal processing chip 121 opposite to the third side via adhesive 135. In this way, the wiring board 151 is positioned adjacent to the signal processing chip 121 and electrically connected to it.

[0031] The configuration using the wiring board 151 as a connection member to the external circuit is not limited to the configuration shown in Figure 4. Figure 5 is a schematic cross-sectional view of the imaging device of Modification 2. The imaging device 300 includes a ring member 161 having a rectangular ring shape. The ring member 161 is placed on the wiring board 151 and surrounds the imaging chip 101. The ring member 161 is formed from a metal such as aluminum, brass, iron, or nickel alloy. Resin can also be used as the material for the ring member 161, or a material in which metal and resin are insert-molded can be used. As will be described in detail later, if it is important to improve the airtightness of the imaging device 300, it is preferable to use metal as the material for the ring member 161. The cover glass 111 is placed on the ring member 161 and bonded by an adhesive layer 131.

[0032] If dust, foreign matter, or other debris adheres to the cover glass 111, or if the cover glass 111 is scratched, these may be reflected in the captured image. By interposing the ring-shaped member 161 between the wiring board 151 and the cover glass 111, the distance between the imaging chip 101 and the cover glass 111 can be increased, thereby reducing the impact of reflections. In addition, stray light due to reflection from the end face of the cover glass 111 becomes less likely to reach the imaging area 102. While the ring-shaped member 161 can increase the distance between the imaging chip 101 and the cover glass 111, the thickness of the imaging device 300 in the z-axis direction becomes thicker compared to when the ring-shaped member 161 is not used. The thickness of the ring-shaped member 161 is adjusted as appropriate from the viewpoint of reducing reflections 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 placed inside the sealed space. If moisture and gases from the external environment enter the inside of the imaging device 300, the imaging performance of the imaging chip 101 will deteriorate. Specifically, if moisture from the external environment enters the sealed space, condensation will form on the imaging chip 101 and the cover glass 111 due to the temperature difference between the inside and outside of the sealed space. Condensation and mold growth caused by condensation distort the formed optical image, thus increasing noise. On the other hand, if gases from the external environment enter the sealed space, they promote oxidation and corrosion of the circuits inside the imaging chip 101, leading to the destruction of the imaging chip 101. By placing the imaging chip 101 inside the sealed space, the imaging chip 101 is less susceptible to the effects of moisture and gases from the external environment, thus suppressing the increase in noise and avoiding the destruction of the imaging chip 101.

[0034] Other configurations using the wiring board 151 as a connection member to an external circuit will be described. Figure 6 is a schematic cross-sectional view of the imaging device of Modification 3.

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

[0036] According to the configuration of the imaging device 400, the pixel signal read from the pixel is first output to the signal processing chip 121 via the through electrode 104. After being processed by the processing circuit of the signal processing chip 121, the pixel signal is output again to the imaging chip 101. Subsequently, it is output to the wiring board 151 via the wire bonding 171.

[0037] In the imaging device 200 shown in Figure 4 and the imaging device 300 shown in Figure 5, the signal processing chip 121 was electrically connected to the wiring board 151. Therefore, the signal processing chip 121 had a through electrode 124 for outputting pixel signals to the wiring board 151. In contrast, the configuration of the imaging device 400 does not have a through electrode 124 in the signal processing chip 121, which is advantageous in terms of manufacturing process and manufacturing cost.

[0038] The configuration in which through electrodes are not formed on the signal processing chip 121 is not limited to the configuration shown in Figure 6. Figure 7 is a schematic cross-sectional view of the imaging device of modified example 4.

[0039] The wiring board 151 of the imaging device 500 has a convex land portion 153 that protrudes toward the region opposite the imaging area 102 (i.e., the opposing region) on the second surface. The land portion 153 is formed in the central part of the wiring board 151, avoiding the region where the signal processing chip 121 is located. The land portion 153 functions as a heat dissipation member that releases heat generated by the imaging chip 101. In other words, the land portion 153 can be said to be a heat dissipation member that abuts against the opposing region. Thus, in the imaging device 500, the heat dissipation member is placed in the space between the two signal processing chips 121. When heat dissipation characteristics are important, the larger the contact surface between the land portion 153 and the imaging chip 101, the better.

[0040] On the other hand, the coefficient of linear expansion of the imaging chip 101 and the wiring board 151 are different. Therefore, when the imaging chip 101 and the wiring board 151 are heated or cooled after being joined, warping occurs in them. This is because the amount of expansion or contraction due to heating or cooling is different for the imaging chip 101 and the wiring board 151. If preventing warping is important, the bonding surface between the land portion 153 and the imaging chip 101 should be as small as possible.

[0041] The wiring board 151 is fixed to the imaging chip 101 via land portions 153 using adhesive 136. An elastic adhesive is preferably used as the adhesive 136. Acrylic resins, silicone resins, epoxy resins, etc., can be used as the elastic adhesive. By using an elastic adhesive as the adhesive 136, stress caused by the difference in the coefficients of thermal expansion between the imaging chip 101 and the wiring board 151 can be absorbed when the imaging chip 101 and the wiring board 151 are heated or cooled after being joined.

[0042] The wiring board 151 and the signal processing chip 121 are in contact 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 connected by the heat dissipation medium 137. This allows the heat generated in the processing circuit of the signal processing chip 121 to be dissipated to the wiring board 151. Therefore, the amount of heat dissipated from the processing circuit to the imaging chip 101 can be reduced.

[0043] Figure 8 is a schematic cross-sectional view of the imaging device according to Modification 5. The wiring board 151 of the imaging device 600 has an opening 155 corresponding to the imaging area 102 and is fixed to the light-receiving surface side of the imaging chip 101. The cover glass 111 covers the opening 155 and is bonded 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 between electrode pads 154 and 106 is bonded by adhesive 139. The adhesive 139 is formed to surround the imaging area 102.

[0045] In the imaging device configuration shown in Figures 4-7, the wiring board 151 is positioned on the side 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 positioned 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 positioned on the imaging chip 101 without using the above-mentioned ring member.

[0046] In the above description, the two signal processing chips 121 were positioned without extending beyond the outer edge of the imaging chip 101 in the x-axis and y-axis directions, but they may be positioned to extend beyond the outer edge of the imaging chip 101. Figure 9 is a schematic cross-sectional view of the imaging device of Modification 6.

[0047] The signal processing chip 121 of the imaging device 700 is provided with electrode pads 127 on its third surface. The electrode pads 127 are formed on the portion of the signal processing chip 121 that extends in the x-axis direction from the outer edge of the imaging chip 101. This configuration allows the electrode pads 127 to be formed on the third surface. Therefore, it is not necessary to form the electrode pads on the surface opposite to the third surface and to form through electrodes to electrically connect the electrode pads. The electrode pads 127 are electrically connected to the electrode pads 145 of the flexible substrate 141 via bumps 140. The connection portion between the electrode pads 127 and 145 is bonded with adhesive 135.

[0048] By positioning the signal processing chip 121 so that it extends beyond 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. As a result, the heat generated by the processing circuit is even less likely to be dissipated to the imaging region 102.

[0049] Even when the two signal processing chips 121 are positioned extending beyond the outer edge of the imaging chip 101 in the x-axis direction, various configurations as described above can be adopted. Figure 10 is a schematic cross-sectional view of the imaging device of Modification 7. The imaging device 800 includes the imaging chip 101, the signal processing chips 121, and the cover glass 111, as well as a wiring board 151 as a connecting member and a ring member 161. 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, with this configuration, the pixel signal output to the signal processing chip 121 can be output to the wiring board 151 without having to output it again to the imaging chip 101. Furthermore, as described above, the ring member 161 makes the imaging chip 101 less susceptible to the effects of moisture and gas in the external environment, thereby suppressing the increase in noise and avoiding damage to the imaging chip 101.

[0050] Figure 11 is a schematic cross-sectional view of the imaging device of Modification 8. The wiring board 151 of the imaging device 900 has convex land portions 153 that protrude toward the opposing region. The wiring board 151 is fixed to the imaging chip 101 by adhesive 136 via the land portions 153. This allows heat generated in the imaging chip 101 to be dissipated. In this way, the imaging device 900 has a heat dissipation member placed in the space between the two signal processing chips 121. Furthermore, by using an elastic adhesive as the adhesive 136, it is possible to absorb stress caused by the difference in the coefficient of linear expansion between the imaging chip 101 and the wiring board 151. The wiring board 151 and the signal processing chip 121 are in contact via a 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.

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

[0052] Figure 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 positioned extending in the positive x-axis direction from the left end of the imaging chip 101. On the other hand, the signal processing chip 121 on the right side is positioned extending in the negative x-axis direction from the right end of the imaging chip 101. The flexible substrate 141 is positioned in the space created by the offsetting of the signal processing chip 121 from the edge of the imaging chip 101. Thus, 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 for miniaturization in the x-axis direction compared to the imaging device 700 shown in Figure 9.

[0053] Figure 14 is a schematic cross-sectional view of the imaging device. The land portions 153 of the wiring board 151 of the imaging device 1200 are formed on the outer edge of the wiring board 151. The wiring board 151 has electrode pads 157 on the land portions 153. The electrode pads 157 are electrically connected to the electrode pads 107 of the imaging chip 101 via bumps 140. Thus, the land portions 153 of the wiring board 151 may be formed in a location other than the central part of the wiring board 151.

[0054] Figure 15 is a schematic cross-sectional view of the imaging device. The wiring board 151 of the imaging device 1300 has an opening 155 corresponding to the signal processing chip 121. The signal processing chip 121 is housed in the opening 155 of the wiring board 151. The electrode pads 157 of the wiring board 151 are electrically connected to the electrode pads 107 of the imaging chip 101 via bumps 140. In this way, when the wiring board 151 and the imaging chip 101 are electrically connected by bump bonding, the wiring board 151 can also be positioned on the side opposite to the light-receiving surface of the imaging chip 101.

[0055] In the above description, the land portion 153 of the wiring board 151, which functions as a heat dissipation member, was bonded to the imaging chip 101. The heat dissipation member may also be bonded to the signal processing chip 121. Figure 16 is a schematic cross-sectional view of the 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 a heat dissipation medium 137. As a result, the heat generated in the signal processing chip 121 is dissipated through the heat dissipation member 181. Therefore, the amount of heat dissipated to the imaging chip 101 can be reduced. As a result, the dark current generated by the heat generated in the signal processing chip 121 can be reduced. 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] Figure 17 is a schematic cross-sectional view of the imaging device. The flexible substrate 141 of the imaging device 1500 is sandwiched between the imaging chip 101 and the signal processing chip 121. The thicknesses of bumps 134 and 132 are different. Specifically, the thickness of bump 132 is greater than the thickness of bump 134 by the thickness of the flexible substrate 141. By devising the thickness of the bumps in this way, a structure in which the flexible substrate 141 is sandwiched between the imaging chip 101 and the signal processing chip 121 can be realized.

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

[0058] The pixel signals from the imaging chip 101 may be transmitted to the signal processing chip 121 by wireless communication utilizing 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 was configured to function as a heat dissipation member that releases heat generated by the imaging chip 101. However, the wiring board 151 and the heat dissipation member do not have to be formed integrally. In addition, heat dissipation members may be individually placed on the imaging chip 101 and the signal processing chip 121, respectively.

[0060] In the above description, the configuration used two signal processing chips 121, but it may also use one. Furthermore, the number of signal processing chips 121 may be three or more. In the above description, a cover glass 111 was used as the optical element, but a low-pass filter, IR cut filter, etc., may be used instead of the cover glass 111.

[0061] Although the present invention has been described above using embodiments, the technical scope of the present invention is not limited to the scope described in the above embodiments. It will be apparent to those skilled in the art that various modifications or improvements can be made to the above embodiments. It will be clear from the claims that such modified or improved forms may 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 Opposing 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 board, 152 Electrode pad, 153 Land area, 154 Electrode pad, 155 Opening, 156 Electrode pad, 157 Electrode pad, 161 Encircling 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 Shooting lens

Claims

[Claim 1] An imaging chip having an imaging unit including a rectangular imaging area in which a first pixel that outputs a first pixel signal generated by photoelectrically converted charge and a second pixel that outputs a second pixel signal generated by photoelectrically converted charge are arranged; a first peripheral portion formed outside the imaging unit; a second peripheral portion formed outside the imaging unit; and a wiring layer including wiring for which the first pixel signal is output and wiring for which the second pixel signal is output. A rectangular chip stacked on the imaging chip in the first peripheral region, a first signal processing chip having a first processing circuit that performs signal processing on the first pixel signal output from the first pixel, In the second peripheral portion, a rectangular-shaped chip stacked on the imaging chip is a second signal processing chip having 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 to which light is incident and a second surface opposite to the first surface. The first pixel and the second pixel are arranged on the first surface side of the wiring layer, The longer side of the first signal processing chip is longer than the shorter side of the imaging area. The longer side of the second signal processing chip is longer than the shorter side of the imaging area. The first signal processing chip and the second signal processing chip are arranged separately from each other, inside the outer edge of the imaging chip. Imaging device.

Images