JPH0195553A - Solid-state image sensing device - Google Patents

Abstract

PURPOSE:To reduce a tilt by a method wherein a wiring film formed on the rear of a transparent sheet, the wiring film and an electrode of a solid-state image sensing device are connected electrically by using an anisotropic conductive film which has been laid between the transparent sheet and the solid-state sensing device. CONSTITUTION:A wiring film 9 is formed on the rear of a transparent sheet 8; this wiring film 9 and electrodes 5 of a solid-state image sensing device 4 are connected electrically by using anisotropic conductive films 10a, 10b which have been laid between the transparent sheet 8 and the solid-state image sensing device 4. A package 1 is pressed toward the transparent sheet 8; it is compressed to the extent that the anisotropic conductive films 10a, 10b become conductive; while this compressed state is being kept and a tilt is being detected, the direction of the package 1 is changed; when the tilt is detected to be 0, the movement of the tilt is stopped; a gap between the package 1 and the transparent sheet 8 is fixed by using a resin 11. By this setup, the tilt can be reduced.

Description

[Detailed description of the invention] The present invention will be described in the following order.

A. Industrial field of application B00 Summary of the invention C0 Prior art 9 Problems to be solved by the invention E1 Means for solving the problem F3 Effects G. Examples [Figures 1 to 3] H99 Effects of the invention (A. Industrial Application Field) The present invention relates to a solid-state imaging device, and particularly to a solid-state imaging device that can reduce tilt.

(B. Summary of the Invention) In order to reduce tilt in a solid-state imaging device, the present invention forms a wiring film on the back surface of a transparent plate, and connects the wiring film and the electrodes of the solid-state imaging device to the transparent plate and solid state. The image pickup elements are electrically connected by an anisotropic conductive film interposed between them.

(C. Background Art) A solid-state imaging device converts an optical image into an electrical signal using a solid-state imaging device such as a CCD or CID. It is often used as a main component of a video camera by being assembled with other members such as.

By the way, solid-state imaging devices are generally disclosed in Japanese Patent Application Laid-open No. 115-1983.
As described in Publication No. 838 or Japanese Unexamined Patent Publication No. 60-74565, a solid-state image sensor is mounted on the inner bottom surface of a package with a substantially concave cross-sectional shape, and the opening on the surface of the package is closed with a glass plate or the like. It has a structure that

(D. Problem to be solved by the invention) By the way, when manufacturing a video camera or the like by assembling a solid-state imaging device into a member such as a lens, the optical axis of the lens is perpendicular to the surface of the solid-state imaging device. It is necessary to do so.

In other words, the deviation of the surface of the solid-state image sensor from perpendicular to the optical axis of the lens is called tilt, and when there is tilt, even if the image is focused at the center of the surface of the solid-state image sensor, the center A phenomenon occurs in which the focus shifts away from the object. Therefore, it is necessary to reduce the size of the 7-ori. In particular, as the resolution of solid-state image sensors becomes higher, it is required to make the dots smaller.

However, it is difficult to make the optical axis of the lens perpendicular to the surface of the solid-state image sensor, and a shift of about several tens of μm to 100 μm occurs.

In the past, a tilt of approximately 2.2 μm was considered unavoidable, but as the resolution of solid-state imaging devices becomes higher, it is now required to reduce the tilt to 10 μm or less.

By the way, the cause of the tilt is that there is a limit to the improvement of the degree of machining of the ceramic package, and there is also non-uniformity in the film bonding the solid-state image sensor, and various errors accumulate.As a result, When assembling the solid-state imaging device into the lens barrel, the top surface of the ceramic package, which serves as a reference surface for positioning, was not completely parallel to the surface of the solid-state imaging device.

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide a solid-state imaging device that can easily obtain an alignment reference plane that is highly parallel to the surface of a solid-state imaging device.

(E. Means for Solving the Problems) In order to solve the above problems, the solid-state imaging device of the present invention forms a wiring film on the back surface of a transparent plate, and connects the wiring film and the electrodes of the solid-state imaging device to the transparent plate. - A feature is that the solid-state imaging devices are electrically connected by an anisotropic conductive film interposed between them.

(F. Effect) According to the solid-state imaging device of the present invention, the anisotropic conductive film originally has elasticity, and has the property of becoming anisotropically conductive when slightly elastically deformed. Therefore, the anisotropic conductive film can be interposed between the transparent plate and the solid-state image sensor, and the tilt can be adjusted in this state. Therefore, by fixing the positional relationship between the transparent plate and the solid-state image sensor when the surface of the solid-state image sensor is not parallel to the surface of the transparent plate, a highly rusty alignment reference plane can be made on the surface of the transparent plate. Therefore, it is possible to obtain a solid-state imaging device having the following characteristics.

(G. Embodiment) [FIGS. 1 to 3] Hereinafter, the solid-state imaging device of the present invention will be described in detail according to the illustrated embodiment.

FIG. 1 is a sectional view showing one embodiment of the solid-state imaging device of the present invention.

In the drawing, 1 is a package made of ceramic, for example, 2 is a wiring film for bonding the solid-state image sensor formed on the inner bottom surface of the package l, and the solid-state image sensor is bonded on the wiring film 2 via an adhesive layer 3 4 is mounted. Reference numeral 5 denotes an electrode formed on the surface of the solid-state image sensor 4, and a large number of electrodes 5 are formed on the peripheral portion of the surface of the solid-state image sensor 4. Reference numeral 6 denotes a wiring film formed from the top surface to the side surface of the package 1. The number of wiring films 6 is the same as the number of electrodes 5 of the solid-state image sensor 4, and the wiring film 6 corresponding to the electrode 5 is located outside the electrode 5. It is located in Each wiring film 6
A lead 7 is connected to each portion located on the side surface of the package.

Reference numeral 8 denotes a transparent plate made of glass, on the back of which a wiring film 9 is provided corresponding to each electrode 5, and serves to connect between the electrode 5 and the corresponding wiring film 6. .

10a and 10b are anisotropic conductive films formed in a ring shape, and the anisotropic conductive film 10a with a smaller diameter is interposed between the solid-state image sensor 4 and the transparent plate 8, and is placed on the surface of the solid-state image sensor 4. serves to electrically connect each electrode 5 and the corresponding wiring film 9. The larger diameter anisotropic conductive film tob is interposed between the package 1 and the transparent plate 8, and is interposed between the wiring film 9 on the back surface of the transparent plate 8 and the wiring film 6 of the package 1.
It plays the role of electrically connecting between Anisotropic conductive film 1
0a and 10b have elasticity and have a property that when compressed in the vertical direction, they become conductive only in the compressed vertical direction.

Reference numeral 11 denotes a resin for fixing the transparent plate 8 to the package 1. The resin 11 is parallel to the surface of the transparent plate 8 or the surface of the solid-state image sensor 4, and the λ-oriented conductive films 10a and 10b are attached to the transparent plate 8.
A transparent plate 8 is bonded to the package 1 so as to maintain a compressed state between the solid-state image sensor 4 and the upper surface of the package 6 to the extent that the package 6 is conductive, and also serves as a seal.

In this solid-state imaging device, the surface of the transparent plate 8 serves as a reference surface S for positioning.

FIGS. 2A to 2F are cross-sectional views showing a method for assembling the solid-state imaging device shown in FIG. 1 in order of steps.

First, as shown in Figure (A), a package 1 on which a solid-state image sensor 4 is mounted, a transparent plate 8, and ring-shaped anisotropic conductive films 10a and 10b are prepared, and then, as shown in Figure (B), Anisotropic conductive IP on package 1 as shown
The transparent plate 8 is properly aligned and placed via 210a and 10b.

Next, the tilt on the surface of the solid-state image sensor 4 is detected from the surface side of the transparent plate 8 using a length measuring device or a focus sensor, and the package 1 is pressed against the transparent plate 8 to form the anisotropic conductive films 10a and 10b. It is compressed to the extent that it becomes conductive. Then, the orientation of the package 1 is changed as shown in FIGS. 2(C) and 2(D) while detecting tilt while keeping the anisotropic conductive films 10a and iob compressed to the extent that they become conductive. As shown in FIG. 5E, when a detection result indicating that the tilt is 0 is obtained, the movement of the package 1 is stopped.

Thereafter, as shown in FIG. 2(F), the space between the package 1 and the transparent plate 8 is fixed with resin 11. Then, the solid-state image sensor 4 on the surface of the transparent plate 8, which becomes the alignment reference surface S,
It is possible to obtain a solid-state imaging device having an extremely high degree of parallelism to the surface, in other words, a highly accurate alignment reference plane. Specifically, the tilt can be reduced to 10 μm or less.

FIG. 3 is a sectional view showing another embodiment of the present invention.

In this embodiment, a bare solid-state image sensor 4, rather than a mounted solid-state image sensor, is bonded to a package made of ceramic or the like through a resin 11, and the leads 7 are soldered to a wiring film 9 on the back surface of a transparent plate 8. This embodiment is different from the embodiment shown in FIG. They are the same in that they are electrically connected by the anisotropic conductive film 10a. The assembly of the solid-state imaging device of this embodiment consists of the electrode 5 of the solid-state imaging device 4 and the wiring film 9 on the back side of the transparent plate 9 (lead soldering has been completed).
A ring-shaped anisotropic conductive film 10a is interposed between the inner end of the anisotropic conductive film 10a, and the tilt adjustment is performed while detecting the tilt of the solid-state image sensor 4 in a state where the anisotropic conductive film 10a is compressed to the extent that it becomes conductive. However, when the tilt disappears, that is, when the surface of the transparent plate 8, which becomes the alignment reference surface S of the solid-state imaging device, becomes parallel to the surface of the solid-state imaging device 4, the solid-state imaging device 4 and the transparent plate 8 are connected in that state. This is done by fixing with resin 11.

Note that 12 is a resin that covers the solid-state image sensor 4, and sealing with the resin 12 is performed after the solid-state image sensor 4 and the transparent plate 8 are adhesively fixed with the resin 11, that is, after the resin 11 is hardened.

(H-Effects of the Invention) As described above, in the solid-state imaging device of the present invention, a pattern of wiring corresponding to the electrodes on the surface of the solid-state image sensor is formed on the back surface of the transparent plate, and each of the wires on the surface of the solid-state image sensor is The electrodes and the corresponding wiring film on the back side of the transparent plate are electrically connected via an anisotropic conductive film interposed between the solid-state image sensor and the transparent plate, and the adhesive material This is characterized in that the positional relationship between the transparent plate and the solid-state image sensor is fixed.

Therefore, according to the solid-state imaging device of the present invention, an anisotropic conductive film that has elasticity and has the property of becoming anisotropically conductive when slightly elastically deformed is used between the transparent plate and the solid-state imaging device. It is possible to adjust the tilt in that state by intervening between the two. Therefore, by fixing the positional relationship between the transparent plate and the solid-state image sensor when the surface of the solid-state image sensor is parallel to the surface of the transparent plate, a reference surface for highly accurate alignment can be created on the surface of the transparent plate. It is possible to obtain a solid-state imaging device having the following.

[Brief explanation of the drawing]

FIG. 1 is a cross-sectional view showing one embodiment of the solid-state imaging device of the present invention, and FIGS. 2(A) to (F) are cross-sectional views showing an example of a method for assembling the solid-state imaging device shown in FIG. 1 in the order of steps. , FIG. 3 is a sectional view showing another embodiment of the solid-state imaging device of the present invention. Explanation of symbols 4... Solid-state image sensor, 5... Electrode, 8... Transparent plate, 9... Wiring film, 10a, iob... Anisotropic conductive film, 11... Adhesive material, S: Reference surface for positioning.

Claims (1)

[Claims] (1) A wiring film corresponding to the electrodes on the surface of the solid-state image sensor is formed on the back surface of the transparent plate, and there is a gap between each electrode on the surface of the solid-state image sensor and the corresponding wiring film on the back surface of the transparent plate. , the solid-state image sensor and the transparent plate are electrically connected via an anisotropic conductive film interposed between them, and the positional relationship between the transparent plate and the solid-state image sensor is fixed by an adhesive. A solid-state imaging device featuring