JP2001085654A - Solid-state image device and manufacturing method thereof - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a device that can realize reduction in size. SOLUTION: A bonding layer A17 is in contact with a Cu foil 15b as the conductive layer formed on one surface of a polyimide film 15a as a resin film forming FPC(Flexible Printed Circuit board). On the other surface of this polyimide film 15a, a Cu foil 15b as a conductive layer is also attached. On an electrode pad 12b of the solid-state image sensing device 12, a bump 12a formed previously of Au or the like is formed, a wiring pattern and bump 12a are electrically connected, and thereby a solid-state image sensing device 12 is mounted on the FPC 15 by placing the bump 12a in contact with the wiring pattern formed of the Cu foil 15b and by depositing this bump with pressure under the heated condition. A bonding layer B14 is provided between the transparent substrate 11 and the solid-state image sensing device 12.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a solid-state imaging device and a method for manufacturing the same.

[0002]

2. Description of the Related Art In a conventional photoelectric conversion imaging apparatus, as shown in FIG. 5, a solid-state imaging device 102 is housed in an opening 101a in a resin or ceramic package 101 having an opening 101a. Is closed with a sealing glass 103.

[0003]

Since the photoelectric conversion imaging device having the above-described structure uses a package, it is possible to suppress the influence of external reflection on the solid-state imaging device.
At present, miniaturization cannot be achieved.

[0004] The present invention has been made in view of the above points, and an object of the present invention is to provide a solid-state imaging device capable of realizing miniaturization and a method of manufacturing the same.

[0005]

Means for Solving the Problems In order to solve the above problems, the present invention has taken the following means. The present invention relates to a solid-state imaging device in which a solid-state imaging device is mounted on a flexible substrate, and a flexible substrate in which a wiring pattern is formed on a resin film, and the flexible substrate is supported. A support substrate, and a solid-state imaging device mounted so as to be electrically connected to the wiring pattern of the flexible substrate, wherein the flexible substrate is provided with a conductive layer via a conductive layer. A solid-state imaging device is provided which is attached to a solid-state imaging device.

According to this structure, the size can be easily reduced. In addition, since the flexible substrate and the supporting substrate are attached with an adhesive or the like via a conductive layer, the bonding reliability can be maintained for a long time as compared with a case where the supporting substrate is attached with a resin film having few polar groups. Can be maintained.

The present invention is also a method of manufacturing a solid-state imaging device having a solid-state imaging device mounted on a flexible substrate,
Forming a conductive layer on the resin film of a flexible substrate formed by forming a wiring pattern on the resin film,
Bonding the flexible substrate to the support substrate so that the conductive layer and the support substrate are in contact with each other; and mounting a solid-state imaging device on the wiring pattern of the flexible substrate. And a method of manufacturing a solid-state imaging device.

According to this method, it is possible to obtain a small-sized solid-state imaging device capable of maintaining adhesion reliability for a long period of time.

[0009]

BEST MODE FOR CARRYING OUT THE INVENTION The main point of the present invention is to provide a solid-state imaging device in which a flexible substrate on which a solid-state imaging device is mounted is attached to a support substrate. To maintain the bonding reliability between the flexible substrate and the supporting substrate for a long period of time.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. FIG. 1 is a plan view showing a solid-state imaging device according to one embodiment of the present invention. FIG.
1 is a back view showing a solid-state imaging device according to one embodiment. FIG. 3 is a sectional view showing the solid-state imaging device according to one embodiment of the present invention. FIG. 4 is an enlarged cross-sectional view taken along line AA ′ of the solid-state imaging device according to one embodiment of the present invention.

In this solid-state imaging device, a flexible printed wiring board (FPC) 15 or a flexible printed circuit (FPC) 15 having a solid-state imaging device 12 mounted on a transparent substrate 11 as a support substrate.
It has a structure in which an AB (Tape Automated Bonding) substrate is attached.

The FPC 15 has a lead portion including an element mounting portion and an external lead 16. An optically transparent transparent substrate 11 is arranged on the side opposite to the solid-state imaging device 12 of the element mounting portion, and a reinforcing plate 13 for a socket is provided on the same side of the external lead portion as the solid-state imaging device 12 if necessary. Are located.

The element mounting portion of the FPC 15 has the structure shown in FIG. That is, the FPC 15 is adhered on the transparent substrate 11 via the adhesive layer A17. Specifically, the adhesive layer A17 is in contact with a Cu foil 15b which is a conductive layer formed on one surface of a polyimide film 15a which is a resin film constituting the FPC. A Cu foil 15b, which is a conductive layer, is also attached to the other surface of the polyimide film 15a. That is,
This polyimide film 15a is sandwiched between Cu foils 15b.

In these two Cu foils 15b, the Cu foil on the transparent substrate 11 side functions as a layer for improving adhesion,
The Cu foil on the solid-state imaging element 12 side functions as a layer for forming a pattern for mounting or wiring the solid-state imaging element and other elements.

On the Cu foil 15b, the solid-state imaging device 1
2 has been implemented. That is, a bump 12a made of Au or the like is formed in advance on the electrode pad 12b of the solid-state imaging device 12, and the bump 12a is applied to a wiring pattern made of a Cu foil 15b plated with Au. The wiring pattern and the bumps 12a are electrically connected to each other by being brought into contact and pressure-bonded under heating, so that the solid-state imaging device 1
2 is mounted on the FPC 15. Also, the bump 12a
Is electrically connected to the external lead 16 by routing the wiring.

An adhesive layer B14 is provided between the transparent substrate 11 and the solid-state imaging device 12. Therefore, the pressure contact state between the bump 12a and the Cu foil 15b is determined by the adhesive B
By 14, the solid-state imaging device 12 is held at the same time as the fixation. For this reason, the electrical connection between them is maintained.

The portion of the FPC facing the imaging surface of the solid-state imaging device 12 has been cut out and removed in advance in order to transmit light. In a solid-state imaging device, an on-chip microlens is usually used, and a gap between the imaging surface and the transparent substrate 11 is a gap in order to prevent the sensitivity of the imaging device from deteriorating. Therefore, the gap between the imaging surface of the solid-state imaging device 12 and the transparent substrate 11 is hermetically sealed by the adhesive layer B14, so that long-term reliability can be maintained.

As described above, a solid-state imaging device in which the FPC 15 on which the solid-state imaging device 12 is mounted is attached to the transparent substrate 11 is configured.

The solid-state imaging device having the above configuration is small in size because the flexible substrate and the supporting substrate are bonded with an adhesive or the like via a conductive layer, and is adhered to a temperature change for a long time. Reliability can be maintained.

Next, a method of manufacturing the solid-state imaging device having the above-described configuration will be described. In the manufacturing method of the solid-state imaging device according to the present embodiment, a Cu foil is formed on the polyimide fill of the FPC, and the FPC is attached to the transparent substrate so that the Cu foil and the transparent substrate are in contact with each other. The solid-state imaging device is mounted on the wiring pattern of the FPC.

The method for forming the Cu foil on the polyimide film is not particularly limited. For example, a Cu foil may be formed on a polyimide film by plating, or a Cu foil may be bonded to the polyimide film. In any case, it is preferable to provide a Cu foil on the polyimide film at the time of manufacturing the FPC. The Cu foil may be subjected to a surface treatment such as Au plating or a surface roughening. In particular, by performing the surface roughening treatment on the Cu foil, the contact area between the Cu foil and the transparent substrate can be increased, and the adhesive strength can be further improved.

The adhesive used when the FPC is adhered to the transparent substrate so that the Cu foil and the transparent substrate are in contact with each other is not particularly limited as long as it has an adhesive force to the transparent substrate and the Cu foil. No restrictions.

When the transparent substrate and the FPC are adhered to each other via the adhesive layer A, the entire surface of the FPC is pressed against a Cu foil, for example, by heating at 150 ° C. for about 1 hour or by ultraviolet curing. .

According to this manufacturing method, it is possible to obtain a small-sized solid-state imaging device capable of maintaining adhesion reliability for a long period of time.

In the above embodiment, the case where a Cu foil is used as the conductive layer interposed between the flexible substrate and the supporting substrate is described. However, in the present invention, another metal is used as the conductive layer. It is also possible to use a layer, for example, a metal film that can constitute an FPC or TAB tape. In the above embodiment, the case where a polyimide film is used as the resin film is described. However, in the present invention, another resin film or the like may be used as the resin film.

In the above embodiment, F is used as the flexible substrate.
The case where a PC is used has been described.
A TAB substrate may be used as the flexible substrate.

In the above embodiment, the case where a Cu foil is used as the conductive layer interposed between the flexible substrate and the transparent substrate has been described. However, in the present invention, another metal is used as the conductive layer. It is also possible to use a layer, for example, a metal film that can constitute an FPC or TAB tape.

The present invention is not limited to the above embodiment, but can be implemented with various modifications. For example, if the solid-state imaging device cannot be sufficiently joined electrically by pressing the solid-state imaging device to the flexible substrate, the electrical joining is appropriately performed using a conductive material such as an Ag paste or an anisotropic conductive film. May be enough. Further, the dimensions, the number, and the like of each member are not limited to the above-described embodiment.

[0029]

As described above, the solid-state imaging device according to the present invention is small in size because the flexible substrate and the supporting substrate are adhered to each other with an adhesive or the like via the conductive layer. Reliability can be maintained.

Further, according to the method of manufacturing a solid-state imaging device of the present invention, a solid-state imaging device capable of maintaining adhesion reliability for a long period of time can be efficiently obtained.

[Brief description of the drawings]

FIG. 1 is a plan view showing a solid-state imaging device according to an embodiment of the present invention.

FIG. 2 is a rear view showing the solid-state imaging device according to one embodiment of the present invention;

FIG. 3 is a sectional view showing a solid-state imaging device according to one embodiment of the present invention;

FIG. 4 illustrates a solid-state imaging device according to an embodiment of the present invention;
It is an expanded sectional view which follows the -A 'line.

FIG. 5 is a cross-sectional view illustrating a configuration of a conventional solid-state imaging device.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 11 ... Transparent substrate, 12 ... Solid-state image sensor, 12a ... Bump, 12b ... Electrode pad, 13 ... Reinforcement plate, 14 ... Adhesive layer B, 15 ... FPC, 15a ... Polyimide film, 15
b: Cu foil, 16: external lead, 17: adhesive layer A.

 ────────────────────────────────────────────────── ─── Continued on the front page (72) Inventor Atsushi Tsukada 6-35, Kita-Shinagawa, Shinagawa-ku, Tokyo F-term (reference) 4M118 AA08 AA10 AB01 HA02 HA24 HA26 HA27 HA31 5C024 AA01 CA31 FA01 FA11

Claims (2)

[Claims] 1. A solid-state imaging device having a solid-state imaging device mounted on a flexible substrate, comprising: a flexible substrate formed by forming a wiring pattern on a resin film; And a solid-state imaging device mounted so as to be electrically connected to the wiring pattern of the flexible substrate. The flexible substrate supports the support via a conductive layer. A solid-state imaging device which is attached to a substrate. 2. A method for manufacturing a solid-state imaging device comprising a flexible substrate and a solid-state imaging device mounted thereon, wherein the wiring pattern is formed on the resin film. A step of forming a conductive layer, a step of attaching the flexible substrate to the support substrate so that the conductive layer and the support substrate are in contact with each other, and a step of attaching the flexible substrate to the wiring pattern of the flexible substrate. Mounting a solid-state imaging device on the solid-state imaging device.