JP2020025332A - Image pickup unit and image pickup device - Google Patents

Abstract

To solve the problem that a warp of a mounting board changes with the passage of time due to a restitutive force originally possessed by the mounting board on which an image pickup chip is mounted.SOLUTION: An image pickup unit comprises an image pickup chip, a mounting board on which an image pickup chip is mounted, and an encircling member bonded with adhesive to the mounting board and encircling the image pickup chip, and a coefficient of thermal expansion of the adhesive while the adhesive is cured is equal to or less than a coefficient of thermal expansion of the encircling member. An image pickup device includes the image pickup unit which includes the image pickup chip, the mounting board on which the image pickup chip is mounted, and the encircling member bonded with adhesive to the mounting board and encircling the image pickup chip, and has the coefficient of thermal expansion of the adhesive while the adhesive is cured being equal to or less than the coefficient of thermal expansion of the encircling member.SELECTED DRAWING: Figure 3

Description

  The present invention relates to an imaging unit and an imaging device.

2. Description of the Related Art An imaging unit having a package structure in which an imaging chip is mounted in a ceramic package is known.
[Prior art documents]
[Patent Document]
[Patent Document 1] Japanese Patent Application Laid-Open No. 2007-01423

  For example, in a manufacturing process of an imaging unit, a mounting substrate on which an imaging chip is mounted may be warped. The warpage of the mounting board may change with time due to the original restoring force of the mounting board.

  In a first aspect of the present invention, an imaging unit includes an imaging chip, a mounting substrate on which the imaging chip is mounted, and a surrounding member adhered to the mounting substrate with an adhesive and surrounding the imaging chip, The coefficient of thermal expansion of the adhesive in a state where the adhesive is cured is equal to or less than the coefficient of thermal expansion of the surrounding member.

  In a second aspect of the present invention, an imaging device includes the above-described imaging unit.

  The above summary of the present invention does not list all of the necessary features of the present invention. Further, a sub-combination of these feature groups can also be an invention.

FIG. 2 is a schematic sectional view of a camera 10 which is an example of an imaging device. FIG. 2 is a top view schematically showing the imaging unit 40. It is sectional drawing which shows the AA cross section of FIG. 2 typically. FIG. 4 is a cross-sectional view schematically illustrating warpage of the mounting board 120. It is sectional drawing which shows typically the imaging unit 500 in another aspect.

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

  FIG. 1 is a schematic sectional view of a camera 10 which is an example of an imaging device. The camera 10 includes a lens unit 20 and a camera body 30. The lens unit 20 is mounted on the camera body 30. The lens unit 20 has an optical system arranged along the optical axis 22 in its lens barrel, and guides an incident subject light beam to the imaging unit 40 of the camera body 30.

  The direction in which the subject light flux enters the imaging chip 100 of the imaging unit 40 is defined as the z-axis direction. The longitudinal direction of the imaging chip 100 is defined as the x-axis direction, and the lateral direction is defined as the y-axis direction. The direction in which the subject light beam travels toward the imaging chip 100 is defined as the z-axis plus direction. In FIG. 1, the direction toward the front of the paper is the plus direction of the x axis, the direction toward the back of the paper is the minus direction of the x axis, the direction toward the bottom of the paper is the plus direction of the y axis, the direction toward the top of the paper is the minus direction of the y axis, The direction toward the right is defined as the plus direction of the z-axis, and the direction toward the left of the paper is defined as the minus direction of the z-axis.

  The camera body 30 includes a main mirror 32 and a sub-mirror 33 behind the body mount 26 connected to the lens mount 24. Unless otherwise specified, the term “rear” refers to the positive direction of the z-axis. The main mirror 32 is rotatably supported between an entrance position where the main unit 32 enters the optical path of the subject light beam emitted from the lens unit 20 and a retracted position where the main mirror 32 retreats from the optical path of the subject light beam. The sub mirror 33 is rotatably supported on the main mirror 32. The sub-mirror 33 enters the entry position together with the main mirror 32, and retreats to the retreat position together with the main mirror 32.

  When the main mirror 32 is at the entrance position, a part of the subject light beam incident on the main mirror 32 is reflected by the main mirror 32 and guided to the focus plate 80. The focus plate 80 is arranged at a position conjugate with the imaging surface of the imaging chip 100 included in the imaging unit 40, and visualizes a subject image formed by the optical system of the lens unit 20. The subject image formed on the focus plate 80 is observed from a finder 86 through a pentaprism 82 and a finder optical system 84.

  When the main mirror 32 is at the entrance position, of the subject light beams incident on the main mirror 32, light beams other than the subject light beam reflected by the main mirror 32 enter the sub mirror 33. Specifically, the main mirror 32 has a half mirror area, and the subject light flux transmitted through the half mirror area of the main mirror 32 enters the sub mirror 33. The sub-mirror 33 reflects the light beam incident from the half mirror area toward the imaging optical system 70. The imaging optical system 70 guides the incident light beam to the focus detection sensor 72. The focus detection sensor 72 outputs a detection result to the MPU 51.

  The focus plate 80, the pentaprism 82, the main mirror 32, and the sub-mirror 33 are supported by a mirror box 60 as a support member. When the main mirror 32 and the sub-mirror 33 are retracted to the retracted position, and the front curtain and the rear curtain of the shutter unit 38 are opened, the subject light flux transmitted through the lens unit 20 is changed to an optical unit disposed behind the shutter unit 38. The light passes through 50 and reaches the imaging surface of the imaging chip 100.

  Behind the imaging unit 40, a substrate 62 and a rear display unit 88 are sequentially arranged. As the rear display unit 88, a liquid crystal panel or the like can be applied. The display surface of the back display unit 88 appears on the back of the camera body 30. The rear display unit 88 displays an image generated from an output signal from the imaging chip 100.

  Electronic circuits such as the MPU 51 and the ASIC 52 are mounted on the board 62. The MPU 51 controls the entire camera 10. An output signal from the imaging chip 100 is output to the ASIC 52 via a flexible printed board or the like. The ASIC 52 processes an output signal output from the imaging chip 100.

  The ASIC 52 generates display image data based on an output signal from the imaging chip 100. The rear display unit 88 displays an image based on the display image data generated by the ASIC 52. The ASIC 52 generates recording image data based on an output signal from the imaging chip 100. The image data for recording generated by the ASIC 52 is recorded on a recording medium mounted on the camera body 30. The recording medium is configured to be detachable from the camera body 30.

  FIG. 2 is a top view schematically showing the imaging unit 40. FIG. FIG. 3 is a cross-sectional view schematically showing an AA cross section of FIG. The imaging unit 40 includes the imaging chip 100, the mounting board 120, the frame 140, and the cover glass 160.

  The imaging chip 100 is a CMOS image sensor or a CCD image sensor. The imaging chip 100 includes an imaging area 101 and a peripheral area 102. The imaging region 101 is formed in a central portion of the imaging chip 100. In the imaging area 101 of the imaging chip 100, a light receiving surface is formed by a plurality of photoelectric conversion elements that photoelectrically convert subject light. The peripheral area 102 of the imaging chip 100 is located around the imaging area 101. The peripheral region 102 of the imaging chip 100 includes a bus driver that reads and outputs a pixel signal obtained by photoelectric conversion in the photoelectric conversion element, and a processing circuit that performs signal processing on the pixel signal output from the bus driver. Have. The processing circuit includes an AD conversion circuit that converts the output pixel signal into a digital signal. The imaging chip 100 is mounted on the mounting substrate 120. The imaging chip 100 is mounted on the mounting substrate 120 by, for example, flip-chip mounting. The imaging chip 100 is electrically connected to the mounting substrate 120 by, for example, wire bonding. The pixel signal converted into a digital signal by the AD conversion circuit of the imaging chip 100 is output to the mounting board 120 via, for example, a wire. The imaging chip 100 is adhered to the mounting substrate 120 with, for example, an adhesive. The imaging chip 100 is housed in the opening 141 of the frame 140.

  The mounting substrate 120 mounts the imaging chip 100. The mounting substrate 120 includes a first layer 121, a core layer 207, and a second layer 122. The first layer 121 includes a solder resist layer 201, a wiring layer 202, an insulating layer 203, a wiring layer 204, an insulating layer 205, and a wiring layer 206. The second layer 122 includes a wiring layer 216, an insulating layer 215, a wiring layer 214, an insulating layer 213, a wiring layer 212, and a solder resist layer 211. Thus, the mounting substrate 120 is a multilayer core substrate having the core layer 207 as a core layer.

  On the mounting substrate 120, along the optical axis 22, the imaging chip 100, the solder resist layer 201, the wiring layer 202, the insulating layer 203, the wiring layer 204, the insulating layer 205, the wiring layer 206, the core layer 207, the wiring layer 216, The layer 215, the wiring layer 214, the insulating layer 213, the wiring layer 212, and the solder resist layer 211 are arranged in this order.

  The insulating layers 203, 205, 215, and 213 are, for example, resin layers. The thickness of each of the insulating layers 203, 205, 215, and 213 is 30 μm to 40 μm. The thickness is a length in the z-axis direction.

  The wiring layer 202, the wiring layer 204, the wiring layer 206, the wiring layer 216, the wiring layer 214, and the wiring layer 212 include a wiring pattern. As a material of the wiring layers 202, 204, 206, 216, 214 and 212, an alloy of nickel and iron (for example, 42 alloy, 56 alloy), copper, aluminum, or the like can be used. The thickness of each of the wiring patterns included in the wiring layers 202, 204, 206, 216, 214, and 212 is about 30 μm to 40 μm. As described above, the first layer 121 includes a three-layer wiring pattern. The second layer 122 includes a three-layer wiring pattern.

  At least a part of the wiring layer 202 is used for a wiring pattern that receives a pixel signal output from the imaging chip 100 via a wire. The wiring pattern of the wiring layer 204 and the wiring pattern of the wiring layer 214 are used, for example, as ground lines. The wiring pattern of the wiring layer 206 and the wiring pattern of the wiring layer 216 are used, for example, as power supply lines. Note that the wiring pattern of the wiring layer 204 and the wiring pattern of the wiring layer 214 may be used as power supply lines, or the wiring pattern of the wiring layer 206 and the wiring pattern of the wiring layer 216 may be used as ground lines.

  The core layer 207 is formed of a resin. For example, the material of the core layer 207 may be FR4. The thickness of the core layer 207 is larger than the thickness of any of the wiring layers 202, 204, 206, 216, 214 and 212. The thickness of the core layer 207 is larger than the thickness of any of the insulating layers 203, 205, 215, and 213. Specifically, the thickness of the core layer 207 is about 0.1 mm to 0.4 mm. The rigidity of the core layer 207 is higher than the rigidity of any of the wiring layers 202, 204, 206, 216, 214, and 212. The rigidity of the core layer 207 may be higher than the rigidity of the first layer 121 and the second layer 122.

  Thus, the mounting substrate 120 is a multilayer core substrate having a resin core. The thickness of the mounting substrate 120 is about 0.3 mm to 1.0 mm as a whole.

  The imaging chip 100 is mounted on the solder resist layer 201. The imaging chip 100 is electrically connected to the wiring layer 202 by the bonding wire 110. The wiring layer 202 and the wiring layer 214 are electrically connected by a via 131 penetrating the first layer 121 and the core layer 207. The via 131 is covered with an insulator 132. The pixel signal output from the imaging chip 100 is transmitted to the wiring layer 212 via the wiring layer 202 and the via 131. A connector is connected to the wiring layer 212. The connector is connected to, for example, a flexible substrate. The pixel signal transmitted to the wiring layer 212 is transmitted to an external electronic circuit such as the ASIC 52 via the connector and the flexible substrate.

  Electronic component 180 is provided on solder resist layer 211. The electronic component 180 is, for example, a capacitor, a resistor, a resistor, or the like. The electronic component 180 forms a power supply circuit that supplies power to a circuit in the imaging chip 100, and the like. The lead member of the electronic component 180 is fixed to the wiring layer 212 with solder or the like. Electronic component 180 and wiring layer 212 are electrically connected by a lead member. As described above, the imaging chip 100 is mounted on the surface of the one mounting substrate 120 opposite to the surface on which the electronic component 180 is provided. As described above, the imaging chip 100 is mounted on the mounting board 120 by COB (Chip On Board).

  The frame 140 is an example of a surrounding member that surrounds the imaging chip 100. The frame 140 is bonded to the mounting substrate 120 by the bonding unit 240. Specifically, the frame 140 is bonded to the solder resist layer 201 of the mounting substrate 120 by the bonding section 240. The bonding section 240 is formed with an adhesive. Specifically, the bonding portion 240 is formed by thermally curing a thermosetting adhesive.

  The frame 140 has a first inner wall surface 142, a first surface 155, a second surface 156, a third surface 157, a fourth surface 158, and a fifth surface 159. The first inner wall surface 142 forms an opening 141. The opening 141 is formed, for example, at the center.

  The first surface 155 is a surface bonded to the cover glass 160 by the bonding unit 260. The first surface 155 is a surface that contacts the end of the first inner wall surface 142. The first surface 155 is a surface formed along the outer edge of the first inner wall surface 142. The first surface 155 is a surface parallel to the xy plane.

  The second surface 156 is a surface in contact with an end of the first surface 155. The second surface 156 is a surface formed along the outer edge of the first surface 155. The second surface 156 has a plane parallel to the yz plane and a plane parallel to the xz plane.

  The third surface 157 is a surface that is in contact with an end of the second surface 156. The third surface 157 is a surface parallel to the xy plane, and is a surface parallel to the first surface 155.

  The fourth surface 158 is a surface that is in contact with an end of the third surface 157. The fourth surface 158 is a surface formed along the outer edge of the third surface 157. The fourth surface 158 has a surface parallel to the yz plane and a surface parallel to the xz plane.

  The fifth surface 159 is a surface that is in contact with the end of the fourth surface 158. The fifth surface 159 is a surface formed along the outer edge of the fourth surface 158. The fifth surface 159 is a surface parallel to the xy plane. The fifth surface 159 is a surface parallel to the first surface 155 and the third surface 157. The fifth surface 159 is a surface bonded to the solder resist layer 201 of the mounting board 120 by the bonding portion 240. The fifth surface 159 is a surface that contacts the end of the first inner wall surface 142. The fifth surface 159 is a surface formed along the outer edge of the first inner wall surface 142.

  The frame 140 has a step formed by the first surface 155, the second surface 156, and the third surface 157. The frame 140 has a mounting hole 146 as a mounting portion. The frame 140 has, for example, three mounting holes 146. Each of the three mounting holes 146 is a hole penetrating from the third surface 157 to the fifth surface 159. All three mounting holes 146 are used to mount other structures. The frame 140 is fixed to another structure by, for example, screwing through three mounting holes 146. Therefore, the imaging unit 40 is fixed to another structure. Note that another structure may be fixed to be in contact with the first surface 155 and the third surface 157 of the frame 140. Other structures may be fixed to contact the first surface 155 and the second surface 156 of the frame 140. Another structure may be fixed to the first surface 155 and the second surface 156 of the frame 140 so as to be in contact with the third surface 157. Other structures include, for example, a mirror box.

  The frame 140 has a positioning hole 147. The frame 140 has, for example, two positioning holes 147. The two positioning holes 147 are holes penetrating from the third surface 157 to the fifth surface 159. All of the positioning holes 147 are used for positioning other structures. One of the two positioning holes 147 is formed by a fitting hole, and the other positioning hole 147 is formed by an elongated hole.

  The frame 140 is positioned to another structure using the two positioning holes 147. For example, by inserting two positioning pins provided on another structure into the two positioning holes 147, the frame 140 and the other structure are positioned. The frame 140 is fixed while being positioned with respect to another structure. Therefore, the imaging unit 40 is fixed to another structure. Other structures include, for example, a mirror box.

  Further, the shutter unit is fixed to the imaging unit 40 or the mirror box. The shutter unit may be fastened together with the imaging unit 40 and the mirror box, for example. In this case, the shutter unit may be positioned with respect to the mirror box using the positioning pins of the mirror box inserted into the positioning holes 147 of the frame 140.

  The frame 140 is configured by inserting a metal body 148 into a resin 149. The metal body 148 is formed in an annular shape so as to surround the opening 141, for example. As a material of the metal body 148, an alloy of nickel and iron (for example, 42 alloy, 56 alloy), copper, or aluminum can be used. If a lightweight material such as aluminum is used as the material of the metal body 148, the weight of the frame 140 can be reduced. If a material having relatively high thermal conductivity such as copper is used as the material of the metal body 148, the heat radiation characteristics from the frame 140 can be improved.

  The cover glass 160 is used to seal the imaging chip 100. The cover glass 160 is bonded to the frame 140 by the bonding unit 260. The cover glass 160 is fixed to the frame 140 so as to cover the opening 141 of the frame 140. The cover glass 160 uses the opening 141 as a sealed space together with the frame 140 and the mounting board 120. The bonding section 260 is formed with an adhesive. Specifically, the bonding section 260 is formed by curing a photocurable adhesive. For example, the bonding section 260 is formed by curing an ultraviolet curable adhesive. As a material of the cover glass 160, borosilicate glass, quartz glass, non-alkali glass, heat-resistant glass, or the like can be used. The thickness of the cover glass 160 is 0.5 mm to 0.8 mm. Since the cover glass 160 has a light-transmitting property, the cover glass 160 and the frame 140 can be bonded to each other using a photocurable adhesive. The cover glass 160 is an example of a translucent member. As the translucent member, quartz or the like can be applied in addition to glass.

  Thus, a sealed space is formed by the mounting board 120, the frame 140, and the cover glass 160. The imaging chip 100 is arranged in a sealed space formed by the mounting substrate 120, the frame 140, and the cover glass 160. This makes the imaging chip 100 less susceptible to the external environment. For example, the imaging chip 100 is less likely to be affected by moisture existing outside the sealed space. Therefore, deterioration of the imaging chip 100 can be prevented.

  When a material having a linear expansion coefficient closest to the linear expansion coefficient of the cover glass 160 (for example, 56 alloy) is used as the material of the metal body 148 of the frame 140, the linear expansion coefficient of the cover glass 160 and the frame 140 can be reduced. Warpage of the frame 140 caused by the difference can be reduced. As a material of the wiring layers 202, 204, 206, 216, 214, and 212 of the mounting substrate 120, a material having a linear expansion coefficient close to that of the imaging chip 100 is used. Is used, the same material may be used as the material of the metal body 148 of the frame 140. Thereby, the warpage of the imaging unit 40 can be reduced. A material having a linear expansion coefficient value close to the linear expansion coefficient value of the imaging chip 100 is, for example, 42 alloy.

  The thickness of the frame 140 will be described. The thickness of the frame 140 is appropriately adjusted from various viewpoints such as securing a distance between the light receiving surface of the imaging chip 100 and the cover glass 160 and rigidity of the frame 140. Here, the reflection on the image caused by the attachment of foreign matter or the like to the cover glass 160 or the scratching can be reduced as the cover glass 160 moves away from the light receiving surface of the imaging chip 100. Therefore, from the viewpoint of reducing the influence of the reflection, it is preferable that the distance between the light receiving surface of the imaging chip 100 and the cover glass 160 is long. Therefore, the thickness of the frame 140 is preferably thicker. The reflection is also affected by the size of the imaging chip 100. For example, the smaller the size of the imaging chip 100 is, the deeper the depth of field is. Therefore, the influence is likely to appear when the distance between the light receiving surface of the imaging chip 100 and the cover glass 160 is short. Therefore, the thickness of the frame 140 is preferably thicker. In addition, from the viewpoint of the rigidity of the frame 140, the thickness of the frame 140 is preferably thick.

  On the other hand, the distance between the light receiving surface of the imaging chip 100 and the cover glass 160 is limited for each model of the imaging device on which the imaging unit 40 is mounted. According to the present embodiment, it is possible to adjust the distance to be limited for each model by the thickness of the frame 140. Further, by providing a thickness, the frame 140 itself can function as a structure to which other structures are directly connected. The thickness of the frame 140 may be from 0.5 mm to 2.0 mm.

  The metal body 148 includes a lower end 151, an upper end 152, and a connecting portion 153 that connects the lower end 151 and the upper end 152. The lower end 151 has, for example, a plane parallel to the xy plane. The upper end 152 has, for example, a plane parallel to the xy plane. The lower end 151 is located on the plus side in the z-axis direction with respect to the upper end 152. The upper end 152 may be formed to be exposed on the outer surface of the frame 140. In this case, the upper end 152 can be attached to another structure while being in contact with the other structure. Therefore, for example, the heat radiation characteristics of the heat generated in the imaging chip 100 can be improved.

  The metal body 148 may be formed so as not to be exposed on the end surface of the lower end 151, that is, the end surface of the frame 140 on the imaging chip 100 side. Since the metal body 148 is covered with the resin 149, reflection on the first inner wall surface 142 of the frame 140 can be suppressed. The lower end 151 may be formed so as to be in direct contact with the wiring layer 202.

  A mounting hole 146 penetrating the upper end 152 and the resin 149 is formed so that the screw 150 can penetrate the portion where the upper end 152 and the resin 149 are laminated. Therefore, the upper end portion 152 forms a part of the inner wall surface 154 of the mounting hole 146. When the frame 140 and another structure are screwed with, for example, a metal screw using the mounting hole 146, the upper end 152 and the screw 150 come into contact with each other. This makes it possible to form a heat transfer path for releasing the heat generated in the imaging chip 100 to the structure via the screw 150. If the entire inner wall surface 154 of the mounting hole 146 is formed by the metal body 148, the heat radiation characteristic of the heat generated in the imaging chip 100 can be further improved.

  FIG. 4 schematically shows the warpage of the mounting substrate 120. In the bonding step of bonding the frame 140 to the mounting substrate 120, the frame 140 is attached to the mounting substrate 120 via the thermosetting adhesive, and is placed in a high-temperature environment higher than room temperature, so that the thermosetting adhesive To cure. After a lapse of time equal to or longer than the curing time of the thermosetting adhesive in a high-temperature environment, the mounting substrate 120 and the frame 140 are returned to room temperature.

  Therefore, the mounting substrate 120 and the frame 140 are subjected to a large temperature change in the bonding process of the frame 140. Due to the difference between the coefficient of thermal expansion of the frame 140 and the coefficient of thermal expansion of the mounting board 120, the frame 140 is deformed by an amount different from that of the mounting board 120. As a result, the mounting substrate 120 may be warped. For example, the periphery of the mounting substrate 120 may be displaced more in the z-axis direction than the center of the mounting substrate 120.

  After the end of the bonding step, a restoring force acts on the mounting substrate 120 to return the mounting substrate 120 to its original state. Therefore, the amount of warpage of the mounting board 120 changes with time. For example, when the amount of warpage of the mounting substrate 120 increases due to a temperature change in the bonding process, the amount of warpage decreases with time due to the restoring force of the mounting substrate 120. If the mounting substrate 120 is greatly warped in the bonding step, the amount of warpage due to the restoring force of the mounting substrate 120 may change over time for a long time. Further, even when the elasticity of the bonding portion for bonding the frame 140 to the mounting board 120 is small, the temporal change in the amount of warpage due to the restoring force of the mounting board 120 may occur for a long time.

  The coefficient of thermal expansion of the thermosetting adhesive used for bonding the frame 140 to the mounting substrate 120 is, for example, equal to or less than the coefficient of thermal expansion of the frame 140. This makes it possible to reduce the amount of warpage that occurs in the bonding process, as compared with the case where the coefficient of thermal expansion of the thermosetting adhesive is larger than the coefficient of thermal expansion of the frame 140. Therefore, it is possible to suppress a change with time in the amount of warpage due to the restoring force of the mounting board 120.

  The volume shrinkage of the thermosetting adhesive used for bonding the frame 140 to the mounting substrate 120 is desirably, for example, 20% or less. The linear expansion coefficient of the thermosetting adhesive is preferably, for example, in the range of 10 ppm / ° C. to 80 ppm / ° C. at a temperature equal to or lower than the glass transition point. The linear expansion coefficient of the thermosetting adhesive is desirably in the range of, for example, 100 ppm / ° C. to 200 ppm / ° C. at a temperature exceeding the glass transition point.

  The elastic modulus of the thermosetting adhesive used for bonding the frame 140 to the mounting board 120 is desirably, for example, 1 GPa or more. The elastic modulus of the thermosetting adhesive used for bonding the frame 140 to the mounting substrate 120 is desirably, for example, 5 GPa or more. The elastic modulus of the thermosetting adhesive used for bonding the frame 140 to the mounting substrate 120 is desirably, for example, 10 GPa or more.

  The elastic modulus of the frame 140 is desirably, for example, 20 GPa or more. The elastic modulus of the frame 140 is desirably, for example, 25 GPa or more. The elastic modulus of the frame 140 is desirably, for example, 30 GPa or more.

  The elastic modulus of the thermosetting adhesive used for bonding the frame 140 to the mounting substrate 120 is, for example, 1/30 or more of the elastic modulus of the frame. The elastic modulus of the thermosetting adhesive used to adhere the frame 140 to the mounting substrate 120 is, for example, 1/5 or more of the elastic modulus of the frame. The elastic modulus of the thermosetting adhesive used to adhere the frame 140 to the mounting substrate 120 is, for example, １ ／ or more of the elastic modulus of the frame. The elastic modulus of the thermosetting adhesive used to adhere the frame 140 to the mounting substrate 120 is, for example, equal to or higher than the elastic modulus of the frame 140. Thus, compared to the case where the elastic modulus of the bonding portion 240 is smaller than the elastic modulus of the frame 140, the bonding portion 240 can suppress the amount of warpage of the mounting substrate 120 from being reduced by the restoring force. Therefore, it is possible to suppress a change with time in the amount of warpage due to the restoring force of the mounting board 120.

  Note that if the thermal expansion coefficient of the thermosetting adhesive is equal to or less than the thermal expansion coefficient of the frame 140, the elastic modulus of the thermosetting adhesive may be smaller than the elastic modulus of the frame 140. If the elastic modulus of the thermosetting adhesive is not less than the elastic modulus of the frame 140, the thermal expansion coefficient of the thermosetting adhesive may be larger than the thermal expansion coefficient of the frame 140. However, it is more preferable that the coefficient of thermal expansion of the thermosetting adhesive be equal to or less than the coefficient of thermal expansion of the frame 140 and that the elastic modulus of the thermosetting adhesive be equal to or more than the elastic modulus of the frame 140.

  It is more desirable that the glass transition point of the thermosetting adhesive be higher. By using a thermosetting adhesive having a high glass transition point, gelation of the bonding portion 240 can be suppressed. Further, the creep resistance of the bonding portion 240 can be improved.

  An epoxy resin-based adhesive may be used as the thermosetting adhesive. The thermosetting adhesive to be used may be a two-component adhesive or a one-component adhesive.

  As described above, the cover glass 160 is adhered to the frame 140 by the photo-curable adhesive. In this case, a high-temperature environment is not required in the step of bonding the cover glass 160 to the frame 140. Therefore, a change in the warped state of the mounting board 120 can be suppressed.

  In the above description, an example in which a resin core is used for the core layer 207 has been described, but the core layer 207 may use a metal core. When the core layer 207 is a metal core, an insulating layer is provided between the wiring layer 206 and the core layer 207 on the first layer 121 of the mounting board 120, and a wiring layer is provided on the second layer 122 of the mounting board 120. An insulating layer is provided between the core layer 216 and the core layer 207. When the core layer 207 is a metal core, an alloy of nickel and iron (for example, 42 alloy, 56 alloy), copper, aluminum, or the like can be used as a material of the core layer 207. The core layer 207 can be used, for example, as a ground.

  Although the mounting substrate 120 has been described using a multilayer substrate having a core layer and six wiring layers, the number of wiring layers is not limited to six. The mounting substrate 120 may be a multilayer substrate having a core layer and two or more wiring layers. The mounting substrate 120 may be a single-layer substrate having a core layer and one wiring layer.

  Further, the mounting substrate 120 may not have the core layer 207. For example, the mounting substrate 120 may be a multilayer substrate having no core layer 207. The mounting substrate 120 may be a single-layer substrate having no core layer.

  Note that the frame 140 may be a frame formed without the metal body 148 being inserted. The frame 140 may be, for example, a resin frame formed of a resin. When the frame 140 is a resin frame, the material forming the frame 140 may be, for example, an epoxy resin. The frame 140 may be a metal frame formed of metal. For example, the frame 140 may be a metal frame formed of a metal including nickel. When the frame 140 is a metal frame, the material forming the frame 140 may be an alloy of nickel and iron (for example, 42 alloy, 56 alloy), copper, aluminum, or the like.

  The adhesive used for bonding the cover glass 160 to the frame 140 may have the same physical properties as the adhesive for bonding the frame 140 to the mounting substrate 120. For example, the adhesive used to bond the cover glass 160 to the frame 140 may have a coefficient of thermal expansion equal to or less than the coefficient of thermal expansion of the cover glass 160. The elastic modulus of the adhesive used to adhere the cover glass 160 to the frame 140 may be equal to or greater than the elastic modulus of the cover glass 160. For example, the adhesive used to bond the cover glass 160 to the frame 140 has a coefficient of thermal expansion equal to or less than the coefficient of thermal expansion of the cover glass 160 and an elastic modulus equal to or greater than the elastic modulus of the cover glass 160. Good. The adhesive used to adhere the cover glass 160 to the frame 140 may have a coefficient of thermal expansion equal to or less than the coefficient of thermal expansion of the cover glass 160 and may have an elastic modulus lower than that of the cover glass 160. The adhesive used to bond the cover glass 160 to the frame 140 may have a lower coefficient of thermal expansion than the coefficient of thermal expansion of the cover glass 160 and an elastic modulus equal to or higher than that of the cover glass 160. Thus, the effect of the warpage of the frame 140 caused by the difference between the coefficient of thermal expansion of the cover glass 160 and the coefficient of thermal expansion of the frame 140 on the warpage of the mounting substrate 120 can be reduced. As described above, the adhesive used to adhere the cover glass 160 to the frame 140 may be a light-curing adhesive or a thermosetting adhesive.

  FIG. 5 is a cross-sectional view schematically illustrating an imaging unit 500 according to another embodiment. The imaging unit 500 includes a mounting substrate 510, an electronic component substrate 520, the imaging chip 100, a cover glass 160, and a frame 140. In the imaging unit 500, members having the same configuration as each part of the imaging unit 40 are denoted by the same reference numerals, and description thereof may be omitted.

  The mounting substrate 510 mounts the imaging chip 100. The mounting substrate 510 is, for example, a ceramic substrate having a ceramic base. The mounting substrate 510 has no core layer. The mounting board 510 may be a single-layer board or a multilayer board.

  Electronic component substrate 520 is a substrate on which electronic component 180 is mounted. The mounting substrate 510 is mounted on the surface of the electronic component substrate 520 opposite to the surface on which the electronic component 180 is mounted. The mounting substrate 510 is mounted on the electronic component substrate 520 using an LGA (Land Grid Array), a BGA (Ball Grid Array), or the like. Electronic component substrate 520 has the same layer configuration as mounting substrate 120. Specifically, the wiring layer 202 in the electronic component substrate 520 has an LGA (Land Grid Array), a BGA (Ball Grid Array), or the like for mounting the mounting substrate 510.

  The frame 140 is bonded to the mounting substrate 510 with a thermosetting adhesive. As the thermosetting adhesive used for bonding between the frame 140 and the mounting board 510, the same physical properties as those of the thermosetting adhesive used for bonding the frame 140 to the mounting board 120 in the imaging unit 40 are used. Thermosetting adhesive can be applied.

  As described in connection with the mounting substrate 120, the number of wiring layers included in the electronic component substrate 520 is not limited to six. The electronic component substrate 520 may be a multilayer substrate having a core layer and two or more wiring layers. The electronic component substrate 520 may be a single-layer substrate having a core layer and one wiring layer. Electronic component substrate 520 may be a multilayer substrate having no core layer.

  As described above, the present invention has been described using the embodiments, but the technical scope of the present invention is not limited to the scope described in the above embodiments. It is apparent to those skilled in the art that various changes or improvements can be made to the above embodiment. It is apparent from the description of the appended claims that embodiments with such changes or improvements can be included in the technical scope of the present invention.

  The execution order of each processing such as operation, procedure, step, and step in the apparatus, system, program, and method shown in the claims, the description, and the drawings is particularly “before”, “before”. It should be noted that they can be realized in any order as long as the output of the previous process is not used in the subsequent process. Even if the operation flow in the claims, the specification, and the drawings is described using "first," "second," or the like for convenience, it means that it is essential to perform the operation in this order. Not something.

10 Camera 20 Lens Unit 22 Optical Axis 24 Lens Mount 26 Body Mount 30 Camera Body 32 Main Mirror 33 Sub Mirror 38 Shutter Unit 40, 500 Imaging Unit 50 Optical Unit 51 MPU
52 ASIC
Reference Signs List 60 mirror box 62 substrate 70 imaging optical system 72 focus detection sensor 80 focus plate 82 pentaprism 84 finder optical system 86 finder 88 rear display unit 100 imaging chip 101 imaging region 102 peripheral region 110 bonding wire 120 mounting substrate 121 first layer 122 Second layer 131 Via 132 Insulator 160 Cover glass 180 Electronic component 140 Frame 141 Opening 142 First inner wall surface 146 Mounting hole 147 Positioning hole 148 Metal body 149 Resin 150 Screw 151 Lower end 152 Upper end 153 Connection 154 Inner wall 155 First surface 156 Second surface 157 Third surface 158 Fourth surface 159 Fifth surface 201, 211 Solder resist layers 202, 204, 206, 212, 214, 216 Wiring layers 203, 205, 213, 215 Insulating layer 207 Core layer 24 , 510 mounting board 260 bonded portion 520 electronic component substrate

Claims (11)

An imaging chip for imaging the subject;
A first surface on which the imaging chip is mounted, a second surface on a side opposite to the first surface, on which a power supply circuit for supplying power to the imaging chip is mounted, A first wiring formed between the first surface and the second surface, the first wiring being formed between the first surface and the second surface, for supplying power from the power supply circuit to the imaging chip; A mounting substrate having a functioning core layer,
A surrounding member surrounding the imaging chip, comprising a metal body bonded by an adhesive in a region outside the region where the imaging chip is mounted on the first surface of the mounting substrate;
The coefficient of thermal expansion of the adhesive in a state where the adhesive is cured is equal to or less than the coefficient of thermal expansion of the surrounding member,
The metal body has a first region that is in contact with the adhesive and a second region that is not in contact with the adhesive,
An imaging unit in which the second region has an attachment portion for attachment to another structure.   The imaging unit according to claim 1, wherein an elastic modulus of the adhesive in a state where the adhesive is cured is equal to or greater than an elastic modulus of the surrounding member. An imaging chip for imaging the subject;
A first surface on which the imaging chip is mounted, a second surface on a side opposite to the first surface, on which a power supply circuit for supplying power to the imaging chip is mounted, A first wiring formed between the first surface and the second surface, the first wiring being formed between the first surface and the second surface, for supplying power from the power supply circuit to the imaging chip; A mounting substrate having a functioning core layer,
A surrounding member surrounding the imaging chip, comprising a metal body adhered to the first surface of the mounting substrate by an adhesive in a region outside the region where the imaging chip is mounted,
The elastic modulus of the adhesive in a state where the adhesive is cured is equal to or higher than the elastic modulus of the surrounding member,
The metal body has a first region that is in contact with the adhesive and a second region that is not in contact with the adhesive,
An imaging unit in which the second region has an attachment portion for attachment to another structure.   4. The imaging unit according to claim 1, wherein the surrounding member is formed of the metal body and a resin. 5.   The imaging unit according to claim 4, wherein the surrounding member is formed by inserting the metal body into the resin.   The imaging unit according to claim 4, further comprising a translucent member fixed to the resin of the surrounding member with an adhesive, and sealing the imaging chip together with the mounting substrate and the surrounding member.   The imaging unit according to claim 6, wherein the translucent member is bonded to the resin of the surrounding member with a photocurable adhesive.   The imaging unit according to any one of claims 1 to 7, wherein a thermal expansion coefficient of the mounting substrate is different from a thermal expansion coefficient of the surrounding member.   9. The imaging unit according to claim 1, wherein a thickness of an adhesive portion formed by the adhesive between the mounting board and the surrounding member is 3 μm or more. 10.   The mounting substrate is formed between the first surface and the second surface, and includes a second wiring that outputs a signal of a subject imaged by the imaging chip, and the first wiring and the second wiring. The imaging unit according to any one of claims 1 to 9, further comprising: a resin layer for insulation.   An imaging apparatus comprising the imaging unit according to any one of claims 1 to 10.

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