JP4372241B2 - Method for manufacturing solid-state imaging device - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a manufacturing method of a solid-state imaging equipment using a CCD or CMOS other solid-state imaging device (bare chip).
[0002]
[Prior art]
2. Description of the Related Art Conventionally, for example, in order to reduce the size and weight of a video camera, it is known that a solid-state imaging device is directly mounted on a printed wiring board without using a package.
[0003]
FIG. 10 shows the main part of this type of conventional solid-state imaging device, and FIG. 11 shows the manufacturing method thereof. In addition, FIG.10 (b) is an enlarged view of the part displayed with the circle | round | yen of Fig.10 (a). In FIG. 10, 1 is a solid-state imaging device such as a CCD, 2 is a protruding electrode formed on an electrode pad 4 provided on the same surface as the light receiving surface 3 of the solid-state imaging device 1, and 5 is an insulating substrate made of, for example, a resin molded package, Reference numeral 6 denotes a connection electrode portion provided in the vicinity of the opening 5 a of the insulating base 5 and is connected to the wiring conductor 16. 7 is a conductive adhesive for electrically connecting the protruding electrode 2 of the solid-state image pickup device 1 and the connection electrode portion 6 of the insulating substrate 5, and 8 is for protecting the light-receiving surface 3 of the solid-state image pickup device 1 from outside. It is a sealant. Note that an imaging optical system (not shown) is mounted on a portion of the back surface side of the insulating base 5 facing the light receiving surface 3 of the solid-state imaging device 1 through the opening 5a.
[0004]
In the method for manufacturing the solid-state imaging device, as shown in FIG. 11A, the light-receiving surface 3 side of the separately manufactured solid-state imaging device 1 is covered with a protective film 9. Peel off. Next, as shown in FIG. 11B, the protruding electrodes (bumps) 2 are formed on the electrode pads 4 of the solid-state imaging device 1. Further, as shown in FIG. 11C, the protruding electrode 2 of the solid-state imaging device 1 is brought into contact with the conductive adhesive film 11 formed uniformly and with a predetermined thickness on the flat plate 10 so that the protrusion A predetermined amount of conductive adhesive 7 is attached to each electrode 2. Next, as shown in FIG. 11 (d), the protruding electrode 2 of the solid-state imaging device 1 is aligned with the connection electrode portion 6 of the insulating base 5 and brought into contact as shown in FIG. 11 (e). Thereafter, the conductive adhesive 7 is cured by heating to electrically connect the protruding electrode 2 and the connection electrode portion 6. Finally, as shown in FIG. 11 (f), the sealant 8 is filled in the gap between the solid-state imaging device 1 and the insulating base 5 around the solid-state imaging device 1, and is cured by heating.
[0005]
[Problems to be solved by the invention]
However, in the above-described conventional solid-state imaging device, in the manufacturing process, after the protective film 9 of the solid-state imaging device 1 is peeled off, the work is performed with the light-receiving surface 3 facing upward, such as when the protruding electrode 2 is formed on the electrode pad 4. Therefore, there is a problem in that dust or the like adheres to the light receiving surface 3 and causes deterioration of characteristics.
[0006]
The present invention seeks to solve the above problems, the protective film covering the light receiving surface of the solid-state imaging device, and peeling in the downward light receiving surface, the solid-state imaging equipment which is adapted for mounting directly to the insulating substrate It aims at providing the manufacturing method of.
[0007]
[Means for Solving the Problems]
To achieve the above object, a method for manufacturing a solid-state imaging device of the present invention includes the steps of: forming a protruding electrode on the connection electrode section provided in the vicinity of the opening portion of the insulating substrate to have a opening, the protruding electrode on A step of transferring the conductive adhesive to the substrate, a step of peeling the protective film provided on the light receiving surface of the solid-state image sensing device with the light receiving surface facing downward, and an electrode pad of the solid-state image sensing device as a protrusion of the insulating substrate aligned with the electrodes, and is characterized in that comprising the step of performing electrical connection with said electrode pad and the bump electrode are bonded with the conductive adhesive.
[0009]
The step of transferring the conductive adhesive onto the protruding electrode is a transfer tool having a protruding portion corresponding to the protruding electrode on the insulating substrate on the conductive adhesive film formed uniformly and with a predetermined thickness on the flat plate. Then, a predetermined amount of conductive adhesive is attached to each of the protrusions, and then the conductive adhesive attached to the protrusions is transferred to the protrusion electrodes on the insulating substrate.
[0010]
According to manufacturing method of the present invention, the solid-state imaging device is peeled off while the protective film was downward, since it can be mounted on the insulating substrate, no step of exposing light-receiving surfaces facing upward, thus Therefore, it is possible to reduce the adhesion of dust to the light receiving surface and prevent characteristic deterioration.
[0011]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
(Embodiment 1)
FIG. 1 shows a solid-state imaging device according to Embodiment 1 of the present invention. FIG. 1B is an enlarged view of a portion indicated by a circle in FIG. The same components as those in the conventional example of FIG. 10 are denoted by the same reference numerals (the same applies hereinafter). That is, in FIG. 1, 1 is a solid-state imaging device such as a CCD, 2 is a protruding electrode, 3 is a light receiving surface of the solid-state imaging device 1, and 4 is an electrode pad formed on the same surface as the light receiving surface 3. Reference numeral 15 is a printed wiring board having a wiring conductor 16 and an opening 15a, 6 is a connection electrode portion disposed in the vicinity of the opening 15a, 7 is a conductive adhesive, and 8 is a shield for the light receiving surface 3 of the solid-state imaging device 1 from the outside. It is a sealing agent for protecting. Note that an imaging optical system (not shown) is mounted on a portion of the back surface side of the printed wiring board 15 facing the light receiving surface 3 of the solid-state imaging device 1 through the opening 15a.
[0012]
In the conventional example of FIG. 10, the protruding electrode 2 is formed on the electrode pad 4 of the solid-state imaging device 1. However, in the first embodiment, the protruding electrode 2 is formed on the connection electrode portion 6 of the printed wiring board 15. Is different. The protruding electrode 2 and the electrode pad 4 of the solid-state imaging device 1 are electrically connected by the conductive adhesive 7.
[0013]
(Embodiment 2)
FIG. 2 shows a solid-state imaging device according to Embodiment 2 of the present invention. FIG. 2B is an enlarged view of a portion indicated by a circle in FIG. In the second embodiment, a resin molded package 5 is used instead of the printed wiring board 15 of the first embodiment.
[0014]
Next, a method for manufacturing the solid-state imaging device according to the second embodiment will be described with reference to FIG. First, as shown in FIG. 3A, the protruding electrode 2 is formed on the connection electrode portion 6 disposed in the vicinity of the opening 5a of the resin molded package 5 having the opening 5a. Reference numeral 16 denotes a wiring conductor connected to the connection electrode portion 6. Next, as shown in FIG. 3B, the conductive adhesive 7 is transferred onto the protruding electrode 2. A method for transferring the conductive adhesive 7 will be described later.
[0015]
Next, as shown in FIG. 3C, the protective film 9 provided on the light receiving surface 3 of the solid-state imaging device 1 is peeled off with the light receiving surface 3 facing downward. Further, as shown in FIG. 3 (d), the electrode pad 4 of the solid-state imaging device 1 is aligned with the protruding electrode 2 of the resin molded package 5, and as shown in FIG. The protruding electrode 2 is bonded with the conductive adhesive 7 and cured by heating to make electrical connection. Finally, although not shown here, the sealant 8 is filled in the gap between the solid-state imaging device 1 and the resin molded package 5 and is cured by heating.
[0016]
FIG. 4 shows a process of transferring the conductive adhesive 7 to the protruding electrode 2 formed on the connection electrode portion 6 of the resin molded package 5. First, a transfer tool 19 having a protruding portion 18 corresponding to the protruding electrode 2 of the resin molded package 5 is prepared. Therefore, as shown in FIGS. 4A to 4C, the protrusion 18 of the transfer tool 19 is formed on the conductive adhesive film 11 formed uniformly and with a predetermined thickness on the flat plate 10. A predetermined amount of the conductive adhesive 7 is adhered to each of the protrusions 18.
[0017]
Next, as shown in FIG. 4D to FIG. 4F, the transfer tool 19 is moved up and down with respect to the resin molded package 5, and the conductive adhesive 7 attached to the protrusions 18 is applied to the resin molded package 5. Is transferred to the protruding electrode 2.
[0018]
FIGS. 5 to 9 show examples of the shape of the protrusion 18 of the transfer tool 19. 5A to 9A are diagrams in which the size of the protruding portion 18 is compared with the size of the protruding electrode 2, and FIG. 5B illustrates the state of the conductive adhesive 7 attached to the protruding portion 18. It is shown.
[0019]
The protrusion 18 a of the transfer tool 19 in FIG. 5 has a diameter A that is equal to or greater than the diameter B of the protruding electrode 2 on the resin molded package 5. 6 has two steps of a first surface having a diameter equal to or larger than the diameter of the protruding electrode 2 and a second surface having a diameter smaller than the diameter of the protruding electrode 2. . 7 has a truncated cone shape or a truncated pyramid shape. The protrusion 18d in FIG. 8 has a hemispherical recess. The protrusion 18e in FIG. 9 has a box-shaped recess. As described above, projections having various shapes can be used.
[0020]
According to the solid-state imaging device of Embodiment 1 or Embodiment 2 or the manufacturing method thereof configured as described above, the protective film 9 is peeled off with the solid-state imaging device 1 facing downward, and the printed wiring board is left as it is. 15 and the resin molded package 5, there is no process in which the exposed light-receiving surface 3 faces upward, and therefore, adhesion of dust to the light-receiving surface 3 is reduced and characteristic deterioration can be prevented. .
[0021]
If a conductive adhesive that removes an oxide film formed on the surface of the electrode pad of the solid-state imaging device, for example, containing an activator such as halogen, is used in the conductive adhesive for the electrode pad. The contact property of the conductive particles is improved.
[0022]
【The invention's effect】
As described above, according to the present invention, in a solid-state imaging device configured by face-down connection of a bare chip of a solid-state imaging device such as a CCD on an insulating substrate, the protective film is peeled off with the solid-state imaging device facing downward. Thus, since it can be mounted on the insulating substrate as it is, adhesion of dust to the exposed light receiving surface is reduced, and there is an effect that characteristic deterioration can be prevented.
[Brief description of the drawings]
FIG. 1 is a cross-sectional view of a solid-state imaging device according to a first embodiment of the present invention. FIG. 2 is a cross-sectional view of a solid-state imaging device according to a second embodiment of the present invention. FIG. 4 is a cross-sectional view of a process for transferring a conductive adhesive to a protruding electrode in the manufacturing process of Embodiment 2 of the present invention. FIG. 5 is a cross-sectional view of a protrusion in a conductive adhesive transfer tool. FIG. 6 is a diagram showing a second shape example of the protrusion in the conductive adhesive transfer tool. FIG. 7 is a third shape example of the protrusion in the conductive adhesive transfer tool. FIG. 8 is a diagram showing a fourth shape example of the protrusion in the conductive adhesive transfer tool. FIG. 9 is a diagram showing a fifth shape example of the protrusion in the conductive adhesive transfer tool. 10 is a cross-sectional view of a conventional solid-state imaging device. FIG. 11 is a conventional solid-state imaging device. Manufacturing process sectional views of a device [Description of symbols]
DESCRIPTION OF SYMBOLS 1 Solid-state image pick-up element 2 Protruding electrode 3 Light-receiving surface 4 Electrode pad 5 Resin molding package 5a Opening part 6 Connection electrode part 7 Conductive adhesive 8 Sealing agent 9 Protective film 10 Plate 11 Conductive adhesive film 15 Printed wiring board 15a Opening part 16 Wiring conductor 18 Protrusion 19 Transfer tool

Claims (8)

Coating and forming a protruding electrode on the connection electrode section provided in the vicinity of the opening portion of the insulating substrate to have a opening, a step of transferring the conductive adhesive onto the protruding electrode, the light-receiving surface of the solid-state imaging device Peeling the protective film with the light receiving surface facing downward, and aligning an electrode pad provided on the same surface as the light receiving surface of the solid-state imaging device with the protruding electrode of the insulating base, A method of manufacturing a solid-state imaging device , comprising the step of performing electrical connection by bonding an electrode to the conductive adhesive . Step of transferring the conductive adhesive on the collision force electrode, the conductive adhesive film formed uniformly and a predetermined thickness on a flat plate, transfer with a protrusion corresponding to the protruding electrode on an insulating substrate A predetermined amount of conductive adhesive is attached to each of the protrusions by contacting a tool, and then the conductive adhesive attached to the protrusions is transferred to the protrusion electrodes on the insulating substrate. A method for manufacturing a solid-state imaging device according to claim 1 . 3. The method of manufacturing a solid-state imaging device according to claim 2 , wherein the protruding portion of the transfer tool has a diameter equal to or larger than the diameter of the protruding electrode on the insulating substrate. Projections of transcription tool has a surface of two-stage of the second surface of smaller diameter than the diameter of the first surface and the protrusion electrode of diameter same diameter or more diameter and a protruding electrode on the insulating substrate The method of manufacturing a solid-state imaging device according to claim 2 . The method for manufacturing a solid-state imaging device according to claim 2 , wherein the protrusion of the transfer tool has a truncated cone shape or a truncated pyramid shape . The method for manufacturing a solid-state imaging device according to claim 2 , wherein the protrusion of the transfer tool has a hemispherical recess . The method for manufacturing a solid-state imaging device according to claim 2 , wherein the protrusion of the transfer tool has a box-shaped recess . 3. The method of manufacturing a solid-state imaging device according to claim 1 , wherein the conductive adhesive contains an activator that removes an oxide film formed on the surface of the electrode pad of the solid-state imaging device.

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