JP2006319124A - Solid state imaging apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To improve the heat dissipation characteristics of a solid state imaging device chip. <P>SOLUTION: In a solid state imaging apparatus 1 wherein the solid state imaging device chip 2 is contained in a box-shaped package 3, the solid state imaging device chip 2 is pinched by a bent flexible wiring board 6, and the flexible wiring board 6 is stuck on the inside of the box-shaped package 3. The solid state imaging device chip 2 and lead terminals 5 of the box-shaped package 3 are electrically connected using lead wiring 7 of the flexible wiring board 6. Thus, the lead wiring 7 can be utilized not only as the electric connection but also as the heat dissipation path for the chip 2, so that the heat dissipation characteristics of the chip is improved. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a solid-state image pickup device in which a solid-state image pickup device chip is housed in a box-shaped package, and more particularly to a solid-state image pickup device that improves heat dissipation performance of the solid-state image pickup device chip.

  The solid-state imaging devices described in the following Patent Documents 1 and 2 are configured so that the light-receiving surface of the solid-state imaging device chip and the glass substrate face each other with the window of the flexible wiring board provided with a window at the center. The electrode pads provided on the periphery of the light receiving surface of the element chip are connected to the wiring of the flexible wiring board, and the two are adhered to each other with a sealing resin, and the flexible wiring board and the glass substrate disposed on the back side thereof are bonded. The solid-state image sensor chip is packaged by closely adhering with an agent.

  The solid-state imaging device having such a structure has an advantage that the structure is simple and can be manufactured at a low cost. However, since the solid-state imaging device chip is exposed to the outside, it is necessary to handle the solid-state imaging device chip so as not to be damaged by impact. . For this reason, normally, as described in Patent Document 3 below, the solid-state imaging device chip is usually sealed in a resin or housed in a box-shaped package.

JP-A-7-99214 JP-A-8-148666 JP-A-6-132441

  In recent years, solid-state imaging devices have increased in number of pixels (multiple pixels) and have increased in operation clock frequency, and the amount of heat generation has increased. For this reason, when the structure in which the solid-state image sensor chip is housed in the box-shaped package is adopted, it is necessary to efficiently conduct heat generated from the solid-state image sensor chip to the package or the outside of the package to cool the solid-state image sensor chip. .

  An object of the present invention is to provide a solid-state imaging device capable of efficiently dissipating heat generated by a solid-state imaging element chip.

  The solid-state imaging device of the present invention is a solid-state imaging device in which a solid-state imaging device chip is housed in a box-shaped package, and the flexible wiring substrate is attached to the box-shaped package by sandwiching the solid-state imaging device chip between folded flexible wiring substrates. The solid-state imaging device chip and the lead terminal of the box-shaped package are electrically connected using the lead wiring of the flexible wiring board.

  The flexible wiring board of the solid-state imaging device of the present invention is provided with a through window that matches the light-receiving surface of the solid-state imaging element chip, and the lead wiring is electrically connected to an electrode pad provided around the light-receiving surface. It is characterized by.

  The solid-state imaging device according to the present invention is characterized in that an opening is provided on a surface where the flexible wiring board is attached to the box package.

  The adhesive material is apply | coated to both the front and back of the said flexible wiring board of the solid-state imaging device of this invention, It is characterized by the above-mentioned.

  The line width of the lead wiring of the solid-state imaging device of the present invention is approximately the same as the electrode pad provided on the solid-state imaging device chip.

  In the solid-state imaging device according to the present invention, a metal plate penetrating the front and back is provided in a portion corresponding to the amplifier portion formed on the solid-state imaging element chip in the portion of the flexible wiring board that contacts the back surface of the solid-state imaging element chip. It is characterized by.

  According to the present invention, compared with the conventional electrical connection by wire bonding, the lead wiring in the flexible wiring board can be used as a heat radiation path of the solid-state image sensor chip, and the cooling performance of the solid-state image sensor chip is improved. Is possible. Further, since wire bonding is not required and inner leads are not required, the manufacturing cost of the solid-state imaging device can be reduced and the size of the device can be reduced.

  Hereinafter, an embodiment of the present invention will be described with reference to the drawings.

  FIG. 1 is a schematic cross-sectional view of a solid-state imaging device according to an embodiment of the present invention. A solid-state imaging device 1 according to the present embodiment includes a solid-state imaging device chip 2, a box-shaped ceramic package 3 that has an opening and accommodates the solid-state imaging device chip 2, and a transparent glass that seals the opening of the package 3. A plate 4. The solid-state image pickup device used in the present embodiment is assumed to be a CCD type (having a floating diffusion amplifier at the output stage of the horizontal transfer path), but the present invention also applies to other types of solid-state image pickup devices such as a CMOS type. Is applicable.

  A plurality of outer lead terminals 5 are formed on the bottom surface of the ceramic package 3, and the end portions of the outer lead terminals 5 are extended so as to be exposed to the outside of the package 3. The flexible wiring board 6 that is bent so as to sandwich the solid-state image sensor chip 2 and is in close contact with the solid-state image sensor chip 2 is housed in the package 3, so that the electrode pads 2 a provided on the surface of the solid-state image sensor chip 2 are formed. The lead wire 7 in the flexible wiring board 6 is electrically connected to the outer lead terminal 5 through the lead wire 7.

  FIG. 2 is a schematic cross-sectional view of the flexible wiring board 6 that is not bent, and FIG. 3 is a schematic bottom view of the flexible wiring board 6. In FIG. 3, since the lead wiring 7 is provided inside the flexible wiring board 6, it should be illustrated with a dotted line, but it is displayed with a solid line to clearly indicate the pattern (hereinafter, FIG. 4, FIG. The same applies to FIGS. 6 and 7.)

  At a predetermined position of the flexible wiring board 6 made of a black insulating material formed in a sheet shape, a through window 11 that matches the light receiving surface of the solid-state imaging device chip 2 and a through hole that substantially matches the through window 11 when folded. A window 12 is drilled.

  A large number of metal lead wirings 7 are provided in the flexible wiring board 6, and each lead wiring 7 has an end portion 7 a exposed on the surface of the flexible wiring board 6 and an end exposed on the back surface of the flexible wiring board 6. Part 7b. Each end 7 a is arranged around the through window 11, and each end 7 b is arranged around the through window 12. Further, a metal plate 13 penetrating from the front surface to the back surface is provided at a position of the flexible wiring board 6 that matches the formation position of the output stage amplifier formed on the solid-state imaging device chip 2. In the illustrated example, each lead wiring 7 has a single layer structure, but may be formed in multiple layers.

  When the solid-state imaging device having such a configuration is assembled, first, as shown in FIG. 2, the back surface of the solid-state imaging device chip 2 is attached to the flexible wiring board 6 so as to cover the through window 12 of the flexible wiring board 6. This affixing can be easily performed by using, for example, the flexible wiring board 6 having an adhesive material applied to the front and back surfaces.

  Next, the flexible wiring board 6 is bent as indicated by an arrow A, and the flexible wiring board 6 is attached to the surface of the solid-state imaging element chip 2. At this time, the through-holes 11 are aligned with the light receiving surface of the solid-state image sensor chip 2, and the respective end portions 7a of the respective lead terminals 7 are electrode pads provided around the light-receiving surface of the solid-state image sensor chip 2. It adheres with a conductive adhesive so that it may be in electrical contact with 2a. Further, the metal plate 13 is brought into close contact with the output stage amplifier position.

  Next, the flexible wiring board 6 bent as described above and sandwiching the solid-state imaging element chip 2 is attached to the bottom surface in the package 3. At this time, each end 7 b of the lead terminal 7 is bonded with a conductive adhesive so as to be in electrical contact with each end of the outer lead terminal 5 in the package 3.

  Finally, the opening of the package 3 is sealed with the transparent glass plate 4 to complete the solid-state imaging device 1. The empty space inside the package 3 may be filled with a transparent resin.

  According to the solid-state imaging device according to the present embodiment, the electrode pad 2a of the solid-state imaging device chip 2 and the outer lead terminal 5 are connected using the flexible wiring board 6, and thus the electrode pads and inner lead terminals that are conventionally required are connected. The bonding process between the two is not necessary, and the assembly work can be facilitated and the cost can be reduced. Also, since the inner lead is unnecessary, the apparatus can be downsized.

  Furthermore, in the solid-state imaging device of the present embodiment, the lead wiring 7 is connected to the outer lead terminal 5 and the electrode pad 2a of the solid-state imaging device chip 2 using the lead wiring 7 that is thicker than the gold wire used for bonding and has a large heat capacity. Heat radiation of the solid-state imaging device chip 2 can be achieved using 7 as a heat radiation path. In addition, by using a lead wire 7 that is as wide as the electrode pad 2, and by using a thick lead wire 7, the heat dissipation capacity of the metal heat dissipation path can be increased. It is possible to improve.

  In addition, since the output stage amplifier portion that generates the largest amount of heat in the solid-state imaging device chip 2 contacts the package 3 via the metal plate 13, the heat generated in the amplifier portion efficiently conducts heat to the package 3 via the metal plate 13. As a result, the heat dissipation performance of the chip 2 is improved.

  Furthermore, in the solid-state imaging device of the present embodiment, since the bottom surface of the solid-state imaging device chip 2 is attached to the package 3 through the flexible wiring board 6 having a thickness, the package 3 has a side (non-parallelism). Even so, this tilt can be absorbed by the thickness of the flexible wiring board 6. Moreover, in this embodiment, since the through hole 12 is provided, even if the tilt is large, the flexible wiring board 6 can easily absorb the tilt, and the influence of the tilt of the package 3 on the solid-state image sensor chip 2 is further reduced. can do.

  The configuration of the flexible wiring board 6 is not limited to the embodiment shown in FIGS. 4, 5, 6, and 7 are schematic plan views of flexible wiring boards 6 according to different embodiments. The folding position when the solid-state image sensor chip is wrapped is indicated by “X” and “Y”. In addition, the same code | symbol is attached | subjected and demonstrated to the member similar to the member shown in FIGS. 1-3.

  In the flexible wiring board 6 of FIG. 4, the back surface of the solid-state imaging device chip is placed on the center 6a of the flexible wiring board 6, and the left and right sides of the flexible wiring board 6 are bent at positions X and Y, respectively. At this time, the left and right end portions 6b and 6c of the flexible wiring board 6 after being bent are spaced apart so as not to block the light receiving surface of the solid-state imaging device chip.

  5 differs from FIG. 4 in that a through hole 11 is provided at the center. The through window 11 may be used to absorb tilt when affixed to the package, or the through window 11 may be an opening of the light receiving surface of the solid-state imaging device.

  The flexible wiring board 6 in FIG. 6 is configured to be folded in half and enclose the solid-state imaging element chip in the same manner as in FIG. 3, but the flexible wiring board 6 is placed in a wide area position where most of the bottom surface of the solid-state imaging element chip abuts. A metal plate 14 penetrating the front and back is provided. Thereby, since the back surface of the solid-state imaging device chip 2 is thermally connected to the package 3 via the metal plate 14, it is possible to further improve the heat dissipation characteristics.

  The flexible wiring board 6 of FIG. 7 has a configuration in which the metal plate 14 is cut out as compared with FIG. 6, and a through window 12 is provided at the notched position of the metal plate 14 to improve the tilt absorption performance. Different.

  Each of the flexible wiring boards 6 of FIGS. 4 to 7 shows the lead wiring 7 thin, but it goes without saying that the characteristic as a heat radiation path is improved as the width is increased so as not to contact the adjacent lead wiring. Absent.

  FIG. 8 is a schematic cross-sectional view of a solid-state imaging device assembled using the flexible wiring board 6 shown in FIG. The through window 11 is disposed on the light receiving surface side of the solid-state image sensor chip 2.

  FIG. 9 is a schematic cross-sectional view of a solid-state imaging device assembled using the flexible wiring board 6 shown in FIG. When the flexible wiring board 6 is bent at the X and Y positions shown in FIG. 4, the end portions 6 b and 6 c are separated from each other and do not cover the light receiving surface of the solid-state imaging device chip 2. In this embodiment, a plurality of vias 9 passing through the bottom of the package 3 are provided as outer lead terminals at the bottom of the package 3, and the lead wiring end 7 b of the flexible wiring board 6 is in electrical contact with each via 9. It is configured to do.

  According to each embodiment described above, the metal lead wiring 7 provided in the flexible wiring board 6 can not only make electrical connection but also dissipate heat from the solid-state imaging element chip, so that the solid-state imaging element chip is efficiently cooled. It becomes possible. Further, since inner lead terminals and bonding are not required, it is possible to reduce manufacturing costs and downsize the apparatus.

  The solid-state imaging device according to the present invention improves the heat dissipation performance of the solid-state imaging device chip, and can reduce the manufacturing cost and the size of the device. Useful as.

It is a cross-sectional schematic diagram of the solid-state imaging device which concerns on one Embodiment of this invention. It is a cross-sectional schematic diagram of the flexible wiring board shown in FIG. It is a top view of the flexible wiring board shown in FIG. It is a top view of the flexible wiring board concerning another embodiment of the present invention. It is a top view of the flexible wiring board concerning another embodiment of the present invention. It is a top view of the flexible wiring board concerning another embodiment of the present invention. It is a top view of the flexible wiring board concerning another embodiment of the present invention. It is a cross-sectional schematic diagram of the solid-state imaging device which concerns on another embodiment of this invention. It is a cross-sectional schematic diagram of the solid-state imaging device which concerns on another embodiment of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Solid-state imaging device 2 Solid-state image pick-up element chip 2a Electrode pad 3 Box-shaped package 4 Transparent glass 5 Outer lead terminal 6 Flexible wiring board 6a Flexible wiring board center part 6b, 6c Flexible wiring board edge part 7 Metal lead terminals 7a, 7b Lead terminal end 9 Via 11, 12 Through window 13 Metal plate

Claims (6)

  In a solid-state imaging device in which a solid-state imaging device chip is housed in a box-shaped package, the solid-state imaging device chip is sandwiched between folded flexible wiring substrates, and the flexible wiring substrate is attached in the box-shaped package. A solid-state image pickup device, wherein the solid-state image pickup device chip and the lead terminal of the box-shaped package are electrically connected with each other.   2. The flexible wiring board is provided with a through window that is aligned with a light receiving surface of the solid-state imaging device chip, and the lead wiring is electrically connected to an electrode pad provided around the light receiving surface. The solid-state imaging device described in 1.   The solid-state imaging device according to claim 1, wherein an opening is provided on a surface where the flexible wiring board is attached to the box-shaped package.   The solid-state imaging device according to any one of claims 1 to 3, wherein an adhesive material is applied to both front and back surfaces of the flexible wiring board.   5. The solid-state imaging device according to claim 1, wherein a line width of the lead wiring is approximately the same as an electrode pad provided on the solid-state imaging element chip.   Of the portion of the flexible wiring board that contacts the back surface of the solid-state imaging device chip, a portion corresponding to the amplifier portion formed on the solid-state imaging device chip is provided with a metal plate penetrating the front and back. The solid-state imaging device according to any one of claims 1 to 5.

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