JP6021618B2 - Imaging apparatus, endoscope, and manufacturing method of imaging apparatus - Google Patents

Description

  The present invention relates to an image pickup apparatus including an image pickup element chip, an endoscope including the image pickup apparatus, and a method for manufacturing the image pickup apparatus, and more particularly to a flat wiring board connected to a junction terminal on the back surface of the image pickup element chip. The present invention relates to an imaging apparatus provided, an endoscope including the imaging apparatus, and a method for manufacturing the imaging apparatus.

  An imaging device including an imaging element chip is used, for example, provided at the distal end portion of an endoscope. In an endoscope, in order to relieve pain of a subject, it is an important issue to reduce the diameter of the tip.

  Japanese Patent Laid-Open No. 2000-199863 discloses an imaging apparatus 101 shown in FIG. The imaging apparatus 101 includes an imaging element chip 120 on which an imaging unit 121 is formed, a pattern film 130, a wiring board 140, and a signal cable 150. The wiring board 140, the electronic component 146 mounted on the wiring board 140, and the distal end side 153 of the signal cable 150 are substantially contained on the projection surface of the imaging element chip 120.

  The wiring board 140 is a T-shaped multilayer ceramic board in which a vertically oriented substrate 140A and a horizontally oriented substrate 140B orthogonal to the substrate 140A are integrally formed. And the bonding pad 122 provided in the outer peripheral part of the image pick-up element 123 and the bonding pad (not shown) provided in the perpendicular | vertical board | substrate 140A couple | bonded with the back surface of the image pick-up element chip 120 formed the wiring pattern. They are connected by a pattern film 130. An electronic component 146 is mounted on the horizontally oriented substrate 140B, and the tip end 153 of the signal cable 150 is connected to the end.

  On the other hand, Japanese Patent Application Laid-Open No. 2011-217887 discloses an imaging device 201 shown in FIG. The imaging device 201 includes a wiring board 230 made of a flexible material including a wiring board 230 disposed on the projection surface 200S of the imaging element chip 220 having the imaging unit 221 formed on the front surface 220SA. The intermediate portion 230M having the terminal 231 joined to the joining terminal 223 of the rear surface 220SB of the back surface 220SB, and the extended portions 230C1 and 230C2 that are bent. And the conducting wire 251 of the signal cable 250 is connected to the electrode 232 of the extending portions 230C1 and 230C2. An electronic component 236 is mounted on the extending portions 230C1 and 230C2. Further, the inner surface of the wiring board 230 is in contact with the block 240 for facilitating the bending work of the wiring board 230 and improving heat dissipation. In the imaging device 201, the wiring board 230, the electronic component 236 mounted on the wiring board 230, and the conductive wire 251 of the signal cable 250 are completely contained on the projection surface of the imaging element chip 220.

  However, in the imaging apparatus 101, the outer dimension increases by the thickness of the pattern film 130 (several tens of μm to several hundreds of μm) by arranging the pattern film 130 on the side surface of the imaging element chip 120. There is a risk that the distal end of the endoscope having an obstacle may become an obstacle. And when the image pick-up element chip | tip 120 becomes smaller, the influence of the thickness of the pattern film 130 will become more remarkable. Further, the wiring board 140 is not easy to manufacture because the substrate 140A and the substrate 140B are integrally formed.

  In addition, since the imaging apparatus 201 includes a process of bending the wiring board 230 connected to the imaging element chip 220, there is a possibility that a defect such as disconnection of the wiring pattern of the wiring board 230 may occur and reliability may be lowered.

JP 2000-199863 A Japanese Unexamined Patent Publication No. 2011-217887

  It is an object of the present invention to provide an imaging device that is highly reliable and easy to manufacture, and an endoscope including the imaging device.

An imaging apparatus according to an embodiment of the present invention has an imaging unit on a front surface, each of which is connected to the imaging unit via a through-wiring, and has a plurality of junction terminals arranged in a first array on the back surface. an imaging element chip having, respectively are bonded to the bonding terminals, a plurality of first terminals disposed in said first array to the first major surface, each connected to the first terminal, the A plurality of second terminals arranged in a second arrangement different from the first arrangement is provided on the second main surface, and the first plate-like first arranged in the projection plane of the imaging element chip A wiring board; a third terminal soldered to the second terminal of the first wiring board; and a fourth terminal connected to the third terminal. A flat second wiring board disposed perpendicularly to the second main surface of the plate and disposed within the projection surface of the imaging element chip , Anda signal cable having a fourth terminal and joined conductors, the second terminal is the second circuit board, is arranged so as to sandwich said third terminal is the second Are arranged on both sides of the wiring board.

An endoscope according to another embodiment has an imaging unit on a front surface, each of which is connected to the imaging unit via a through-wiring, and has a plurality of junction terminals arranged in a first array on the back surface an imaging element chip, each joined to the bonding terminals, a plurality of first terminals disposed in said first array to the first major surface, each connected to the first terminal, the second A plurality of second terminals arranged in a second arrangement different from the arrangement of the first arrangement on the second main surface, and a flat plate-like first wiring arranged in the projection plane of the image sensor chip A first terminal connected to the third terminal, and a third terminal soldered to the second terminal of the first wiring board; and a fourth terminal connected to the third terminal. A second wiring board in the form of a flat plate disposed in the projection plane of the imaging device chip, and perpendicular to the second main surface of the imaging element chip, A signal cable having a 4 terminal and joined conductors, comprising a said second terminal is the second circuit board, it is arranged so as to sandwich said third said the terminal second wiring board An insertion unit in which imaging devices arranged on both sides of the insertion unit are disposed at a distal end portion, an operation unit disposed on a proximal end side of the insertion unit, and a universal cord extending from the operation unit, It has.

  According to the present invention, it is possible to provide an imaging apparatus that is highly reliable and easy to manufacture, and an endoscope including the imaging apparatus.

It is a perspective view of a well-known imaging device. It is an exploded view of a well-known imaging device. It is sectional drawing for demonstrating the structure of the imaging device of 1st Embodiment. It is an exploded view for demonstrating the structure of the imaging device of 1st Embodiment. It is a top view of the 1st main surface of the 1st wiring board of the imaging device of a 1st embodiment. It is a top view of the 2nd main surface of the 1st wiring board of the imaging device of a 1st embodiment. It is a disassembled perspective view of the junction part of the 1st wiring board and 2nd wiring board of the imaging device of 1st Embodiment. It is an exploded sectional view of the joined part of the 1st wiring board and the 2nd wiring board of the imaging device of a 2nd embodiment. It is a disassembled perspective view of the junction part of the 1st wiring board and 2nd wiring board of the imaging device of 3rd Embodiment. It is a perspective view of the endoscope of a 4th embodiment.

<First Embodiment>
The imaging apparatus 1 according to the present embodiment will be described with reference to FIGS. In addition, the figure is a schematic diagram for explanation, and a vertical / horizontal dimensional ratio and the like are different from actual ones. In addition, illustration of some components is omitted, and in the cross-sectional view, some components are displayed as viewed from the side.

  As shown in FIGS. 3 and 4, the imaging device 1 includes a cover glass 10, an imaging element chip 20, a first wiring board 30, and a second wiring board disposed perpendicular to the first wiring board 30. Wiring board 40 and a signal cable (hereinafter also referred to as “cable”) 50.

  An imaging unit 21 such as a CMOS element is formed on the front surface 20SA of the imaging element chip 20, and the imaging unit 21 is a junction terminal of the back surface 20SB via a through wiring 22 made of TSV (Through-Silicon Via) or the like. 23. Note that a wiring layer having a multilayer wiring structure is formed on the back surface 20SB of the imaging element chip 20, but this is not shown. Bumps 24 made of solder are formed on the junction terminals 23. That is, the image sensor chip 20 is packaged in a so-called CSP (Chip size package) type.

  The micro lens 12 is disposed in the imaging unit 21, and a cover glass 10 that protects the imaging unit 21 is bonded via the bonding layer 11. Note that a plurality of imaging element chips 20 are collectively manufactured on a semiconductor wafer by a known wafer process. A cover glass 10 is obtained by cutting a glass wafer bonded to a semiconductor wafer together with the semiconductor wafer in order to protect the imaging unit 21 during the wafer process. For this reason, the outer dimension (plan view dimension) of the imaging element chip 20 and the outer dimension of the cover glass 10 are the same.

  The first wiring board 30, the second wiring board 40, and the conductive wire 51 are all arranged inside the projection surface 20 </ b> S of the imaging element chip 20.

  As shown in FIGS. 5A and 5B, the first wiring board 30 has a plurality of first terminals 41 on the first main surface 30SA, and a plurality of second terminals 42 on the second main surface. Have. The arrangement of the plurality of first terminals 41 (first arrangement) is different from the arrangement of the second terminals 42 (second arrangement). That is, the first wiring board 30 is a terminal array conversion wiring board.

  The wiring that performs terminal arrangement conversion is an internal wiring of the first wiring board 30 that is, for example, a multilayer wiring board. Of course, a part of the terminal array conversion wiring may be formed on the first main surface 30SA or the second main surface 30SB.

  The first wiring board 30 has a plurality of first terminals 41 in the central region of the first main surface 30SA, but has a second terminal 42 in the central region of the second main surface 30SB. Not. This is because the first array is the same as the array of the junction terminals 23 of the image sensor chip 20. In order to improve the bonding strength between the first wiring board 30 and the imaging element chip 20 and to prevent a short circuit between the terminals, the arrangement of the plurality of bonding terminals 23 on the back surface 20SB of the imaging element chip 20 is arranged in the central region. This is the first array in which the junction terminals 23 are disposed.

  On the other hand, since the 2nd wiring board 40 is joined to the center area | region of 2nd main surface 30SB of the 1st wiring board 30, the 2nd terminal 42 cannot be formed. For this reason, the arrangement | sequence of the some 2nd terminal 42 is a 2nd arrangement | sequence which does not have the 2nd terminal 42 in a center area | region.

  The first wiring board 30 is a terminal arrangement conversion wiring board that converts the first arrangement of the first main surface 30SA into the second arrangement of the second main surface.

  As shown in FIGS. 5A and 5B, in the imaging device 1, the first terminal 31 joined to the joining terminal 23 (bump 24) of the imaging element chip 20 is substantially circular. On the other hand, the second terminal 33 joined to the third terminal 41 of the second wiring board 40 is substantially rectangular. Further, since the plurality of first terminals 31 are connected by the terminal array conversion wiring, the number of the first terminals 31 is 15, but the number of the second terminals 33 is 9.

  That is, the first terminal 31 and the second terminal 33 may differ not only in arrangement but also in at least one of shape, size, and number.

  The second wiring board 40 joined perpendicularly to the central region of the second main surface 30SB of the first wiring board 30 is connected to the second terminal 33 of the first wiring board 30 at both ends. The third terminal 41 is provided. The third terminal 41 is connected to the fourth terminal 42 at the other end via the wiring 43. The fourth terminal 42 is joined to the conducting wire 51 of the cable 50.

  In the middle of the wiring 43, that is, between the third terminal 41 and the fourth terminal 42, an electronic component 46 such as a chip capacitor, a chip inductor, or a semiconductor chip is surface-mounted via a solder 47. The electronic component mounting method may be a wire bonding method, a TAB (Tape Automated Bonding) method, or the like. Further, the second wiring board 30 may be a wiring board containing electronic components.

  The joint terminal 23 of the image pickup device chip 20 and the first terminal 31 of the first wiring board 30 are solder-joined via bumps 24, and the joint portion is a sealing resin 25 such as an epoxy thermosetting resin, for example. It is sealed with. The bump 24 may be Au, Ag, Cu, or the like. The joining terminal 23 and the first terminal 31 are joined by thermocompression bonding, ultrasonic thermocompression bonding, conductive paste, NCP (Non Conductive Paste), NCF (Non Conductive Film), ACP (anisotropic conductivity). Film) or ACF (anisotropic conductive paste). On the other hand, the sealing resin 25 may be silicone, polyimide, phenol, acrylic, urethane, or the like instead of epoxy, and the curing method may be thermosetting type, UV curing type, UV curing + Thermosetting type may be used. Furthermore, in order to improve heat dissipation, a resin containing a filler having a high thermal conductivity may be used.

  As shown in FIG. 6, the second wiring board 40 is fixed vertically to the approximate center of the second main surface 30SB of the first wiring board 30 via an adhesive (not shown). In addition, you may form the recessed part which the 2nd wiring board 40 fits in 2nd main surface 30SB of the 1st wiring board 30. FIG. Workability is improved because joining work can be performed simply by fitting. Further, since the joint is reinforced, the reliability is improved. Further, when no adhesive is required for joining, the cost can be reduced.

  Then, the second terminal 33 of the first wiring board 30 and the third terminal 41 of the second wiring board 40 are joined via the solder 39. You may cover the junction part of the 2nd terminal 33 and the 3rd terminal 41 with resin etc. for reinforcement.

  In addition, the manufacturing method of the imaging device 1 includes a plurality of solder joining steps. It is preferable that the solder used in the plurality of solder joining steps has a composition with different melting temperatures in order to improve workability or reliability. For example, if the melting temperature is (A) below, workability is improved, and if it is (B) below, thermal degradation of the imaging unit 21 can be prevented.

  (A) Solder bump 24> solder 47 for mounting electronic components> solder 39 for joining the second terminal 33 and the third terminal 41 for joining the imaging element chip 20 and the first wiring board 30

  (B) Solder 47> Solder 39> Solder bump 24

  The first wiring board 30 and the second wiring board 40 are so-called rigid wiring boards that are flat and made of glass epoxy resin, metal, ceramic, or the like and have no flexibility. In particular, a metal having a high thermal conductivity or a ceramic such as aluminum nitride is preferably used.

  The imaging device 1 is highly reliable and easy to manufacture. That is, since the wiring board is not a flexible wiring board but a rigid wiring board, the reliability of the electrical joint is high. Moreover, since it can produce by joining two types of wiring boards, manufacture is easy. Furthermore, the heat generated by the imaging unit 21 can be efficiently radiated by using a wiring board having high thermal conductivity. Furthermore, the wiring board can be placed in a narrow space without being bent in the manufacturing process.

Second Embodiment
Next, an imaging apparatus 1A according to the second embodiment will be described with reference to FIG. Since the image capturing apparatus 1A is similar to the image capturing apparatus 1, the same components are denoted by the same reference numerals and description thereof is omitted.

  As shown in FIG. 7, in the imaging apparatus 1 </ b> A, the first wiring board 30 and the second wiring board 40 are joined using pins 40 </ b> P that are fixing members. That is, the pin 40 </ b> P disposed on the end surface of the second wiring board 40 is fitted into the hole 30 </ b> H formed in the first wiring board 30.

  A pin that is a fixing member may be disposed on the first wiring board 30, and a hole that fits into the pin may be formed on the end surface of the second wiring board 40. Moreover, the adhesive agent may be apply | coated to the joint surface. Further, the hole may be a through hole, or a pin may be joined with solder or an adhesive inside the hole.

  The imaging device 1A has the effect of the imaging device 1, and further, the first wiring board 30 and the second wiring board 40 are strong and the reliability is improved. Further, the first wiring board 30 and the second wiring board 40 can be easily aligned, and workability is improved. Furthermore, soldering of the joint is easy and workability is improved.

<Third Embodiment>
Next, an imaging apparatus 1B according to the third embodiment will be described with reference to FIG. Since the imaging device 1B is similar to the imaging devices 1 and 1A, the same components are denoted by the same reference numerals, and description thereof is omitted.

  As shown in FIG. 8, in the imaging apparatus 1 </ b> A, the first wiring board 30 and the second wiring board 40 are joined by solder 49 using an L-shaped member 48 that is a fixing member. The L-shaped member 48 is made of a conductive metal material having excellent solderability, such as copper or nickel. A copper film or the like may be formed on the surface of stainless steel or the like.

  The imaging device 1B joined using the L-shaped member 48 has the effect of the imaging device 1, and further, the first wiring board 30 and the second wiring board 40 are strong, and the reliability is improved. Further, the first wiring board 30 and the second wiring board 40 can be easily aligned, and workability is improved. Furthermore, soldering is easy and workability is improved.

  Of course, the imaging apparatus 1A may also have pins 40P and the like that join the first wiring board 30 and the second wiring board 40 as in the imaging apparatus 1A.

<Fourth embodiment>
Next, an endoscope 9 according to a fourth embodiment will be described.

  As shown in FIG. 9, the endoscope 9 is provided with the imaging device 1, the imaging device 1 </ b> A, or the imaging device 1 </ b> B provided at the distal end portion 2 and the proximal end side of the insertion portion 3. An operation unit 4 and a universal cord 5 extending from the operation unit 4 are provided.

  Since the endoscope 9 includes the imaging device 1 and the like having high connection reliability between the imaging element chip 20 and the signal cable 50, the endoscope 9 has high reliability. Further, in the imaging device 1 and the like, since the constituent elements are disposed in the projection plane of the imaging element chip 20, the tip portion 2 has a small diameter.

  The present invention is not limited to the above-described embodiment, and various changes and modifications can be made without departing from the scope of the present invention.

DESCRIPTION OF SYMBOLS 1, 1A, 1B ... Imaging device, 9 ... Endoscope, 10 ... Cover glass, 20 ... Imaging element chip, 21 ... Imaging part, 22 ... Through wiring, 23. ..Junction terminals, 24... Bumps, 25... Sealing resin, 30... First wiring board, 31. Solder, 40 ... second wiring board, 41 ... third terminal, 42 ... fourth terminal, 43 ... wiring, 46 ... electronic component, 48 ... L-shaped Mold member, 49 ... solder, 50 ... signal cable, 51 ... conductor, 59 ... solder

Claims (5)

An imaging element chip having an imaging unit on the front surface, each of which is connected to the imaging unit via a through-wiring and having a plurality of junction terminals arranged in a first array on the back surface;
Each been bonded to the bonding terminals, said first plurality of first arranged in an array of terminals having a first major surface, are connected respectively to the first terminal, said first sequence A plurality of second terminals arranged in a second arrangement different from the second main surface on the second main surface, and a flat first wiring board disposed in the projection surface of the imaging element chip;
A third terminal which is the second terminal and the solder joint of the first wiring board, and a fourth terminal coupled to the third terminal, has, above the first wiring board A flat second wiring board disposed perpendicular to the second main surface and disposed in the projection plane of the imaging element chip;
A signal cable having a conducting wire joined to the fourth terminal,
An imaging apparatus, wherein the second terminal is disposed so as to sandwich the second wiring board, and the third terminal is arranged on both surfaces of the second wiring board .   The first wiring board has the first terminal at the center of the first main surface, and the second main surface of the second main surface is joined to the second wiring board at the center. The imaging device according to claim 1, wherein the imaging device is not provided.   The imaging apparatus according to claim 2, further comprising a fixing member that arranges the second wiring board perpendicularly to the second main surface of the first wiring board. The fixing member is an L-shaped member made of a conductive material joined to the second terminal of the first wiring board and the third terminal of the second wiring board. The imaging device according to claim 3.   The imaging device according to any one of claims 1 to 4, wherein the imaging device is disposed at a distal end portion thereof, an operation portion disposed on a proximal end side of the insertion portion, and extending from the operation portion. An endoscope comprising: a universal cord that exits.

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