JPH01228178A - Solid state image sensor - Google Patents

Abstract

PURPOSE:To prevent a adhesive from being left unremoved on an image sensor mounting face and decrease the deviation between a photodetective face and the position of the focus of a camera by a method wherein the image sensor mounting face of a mounting base is made lower than a bonding plane of the mounting base where a transparent sealing cap is bonded. CONSTITUTION:A solid state image sensing element chip 3 mounted on a mounting face 2A of the surface of a mounting base 2 is sealed in a transparent sealing cap 4, and the transparent sealing cap 4 is fixed to a bonding face 2B of the surface of the mounting base 2 through adhesive 6. An image sensor mounting face 7 is provided on a peripheral part 2C of the surface of the mounting base 2, and the image sensor packaging face 7 is made, at least, lower than the bonding face 2B of the surface of the mounting base 2. By these processes, even if the transparent sealing cap 4 is positionally deviated at the bonding of it to the surface of the mounting base 2, the adhesive 6 is prevented from attaching to the image sensor mounting face 7, so that the deviation of a photodetecting face form the focus of a camera can be reduced.

Description

[Detailed Description of the Invention] [Field of Industrial Application] The present invention relates to a solid-state imaging device, and particularly to a solid-state imaging device in which a solid-state imaging device chip mounted on a mounting surface of a mounting board is sealed with a sealing cap. It relates to techniques that can be applied and are effective.

[Conventional technology]

In a solid-state imaging device currently being developed by the present inventor, a solid-state imaging element chip mounted on a mounting surface of a mounting substrate (base substrate) is sealed with a transparent sealing cap.

The mounting board has a plate shape. The mounting surface is provided at the center of the surface of the mounting board.

External terminal (ponding pad) of solid-state image sensor chip
are connected to internal terminals placed on the surface of the mounting board using bonding wires. The internal terminals are connected to external terminals arranged on the back surface of the mounting board through wiring in connection holes formed in the mounting board.

The surface of the solid-state image sensor chip mainly includes a light-receiving surface (photosensor array) on which photosensors are arranged and a CCD shift register.

The transparent sealing cap is made of a transparent resin material in which a light transmitting portion and a portion corresponding to a frame forming a cavity are integrally molded. This transparent sealing cap is fixed to the surface of the mounting board with adhesive.

As the adhesive, a fast-curing liquid adhesive such as a glass epoxy-based ultraviolet curable resin adhesive is used.

The solid-state imaging device configured in this manner has an external terminal corresponding to an outer lead within the area occupied by the mounting board, and therefore has a feature that it can be miniaturized.

1 on the peripheral part of the surface of the mounting board of the solid-state imaging device mentioned above.
For example, a device mounting surface (a surface used for positioning when mounting the device) that comes into contact with the mounting reference surface of the camera frame is provided. In other words, the solid-state imaging device sets the inclination of the light-receiving surface (photosensor array) with respect to the camera by bringing the device mounting surface of the peripheral portion of the mounting board into contact with the mounting reference surface of the camera frame and maintaining that state. ing.

The solid-state imaging device of this type, which is currently being developed by the present inventor, is described in, for example, Japanese Patent Application No. 1984-1944, previously filed by the applicant of the present application.

[Problem to be solved by the invention]

The solid-state imaging device described above is assembled on an automated line as follows. First, a solid-state image sensor chip is mounted on the mounting surface of a mounting board. Next, after applying an adhesive to the adhesive surface of the transparent sealing cap, the transparent sealing cap is sucked by a vacuum suction device, and transported and placed on the mounting surface of the mounting substrate. Next, the position of the transparent sealing cap relative to the mounting substrate is corrected using a positioning jig. Then, the adhesive is irradiated with ultraviolet rays to fix the transparent sealing cap to the mounting substrate. In the solid-state image transfer device assembled in this manner, when the position of the transparent sealing cap with respect to the mounting substrate is corrected as described above, adhesive remains on the device mounting surface of the peripheral portion of the mounting substrate. The adhesive remaining on the device mounting surface of the mounting board causes the light-receiving surface to tilt when the solid-state imaging device is mounted on a camera. For this reason, there has been a problem in that the position of the focal point of the camera and the light receiving surface of the solid-state imaging device are misaligned.

Furthermore, since the adhesive remaining on the device mounting surface of the mounting board has elasticity, there is a problem in that the solid-state imaging device cannot be stably attached when mounted on a camera.

Furthermore, if adhesive remains on the device mounting surface of the mounting board, the solid-state imaging device is selected as a defective product by an external defect inspection. For this reason, there is a problem in that the yield rate decreases in the assembly process of the solid-state imaging device.

An object of the present invention is to provide a technique that can prevent adhesive from remaining on the device mounting surface of a mounting board in a solid-state imaging device.

Another object of the present invention is to provide a technique that achieves the above object and can reduce the misalignment between the light-receiving surface of a solid-state imaging device and the focal point of a camera.

Another object of the present invention is to provide a technique that can improve the yield in the assembly process of the solid-state imaging device.

The above and other objects and novel features of the present invention will become apparent from the description of this specification and the accompanying drawings.

[Means to solve the problem]

A brief overview of typical inventions disclosed in this application is as follows.

In the solid-state imaging device, the device mounting surface of the mounting substrate is configured to be lower than the bonding surface of the mounting substrate to which the transparent sealing cap is bonded.

[For production]

According to the above-mentioned means, when adhering the transparent sealing cap to the surface of the mounting board, even if the transparent sealing cap is misaligned, it is possible to prevent the adhesive from adhering to the device mounting surface. As a result, when the solid-state imaging device is mounted on a device such as a camera, it is possible to reduce the tilt that occurs on the light-receiving surface of the solid-state image sensor chip. can be reduced.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The structure of the present invention will be described below along with an embodiment in which the present invention is applied to a solid-state imaging device in which a solid-state imaging device chip made of a -dimensional CCD photosensor is sealed.

Note that throughout the description of the embodiments, parts having the same functions are given the same reference numerals, and repeated explanations thereof will be omitted.

[Example of interrogation letter]

The configuration of a solid-state imaging device that is an embodiment of the present invention is shown in Figure 1 (
(plan view) and FIG. 2 (partial sectional view).

As shown in FIGS. 1 and 2, in the solid-state imaging device 1, a solid-state imaging device chip 3 mounted on a mounting surface 2A on the surface of a mounting substrate (base substrate) 2 is sealed with a transparent sealing cap 4. ing. The mounting substrate 2 and the transparent sealing cap 4 constitute a package member of the solid-state imaging device 1.

The mounting board 2 is configured in a substantially flat plate shape,
It has a hexagonal shape with chamfered sides.

The long side of the mounting board 2 has a dimension of, for example, about 5 to 6 [mm]. The short side has a dimension of, for example, about 4 to 5 mm.

The thickness is, for example, approximately 0.5 to 0.8 mm. The mounting board 2 is composed of a ceramic single-layer board or a multilayer board in which ceramic boards are laminated in multiple layers. The mounting board 2 is not limited to ceramic material, and may be made of a resin board such as epoxy resin.

The mounting surface 2A is provided at the center of the surface of the mounting board 2. The solid-state image sensor chip 3 mounted on the mounting surface 2A is composed of a one-dimensional CCD photosensor whose details are not shown. In other words, the solid-state image sensor chip 3
The device mainly includes a light-receiving surface and a CCD shift register on the surface of a single-crystal silicon substrate. The light receiving surface is composed of a photosensor array including a plurality of photosensors (photodiode elements) arranged in a -dimensional manner.

The CCD shift register is arranged along the array of photosensors on the light receiving surface. External terminals (ponding pads) are arranged around the solid-state image sensor chip 3.

Although not shown, the external terminals of the solid-state image sensor chip 3 are connected to internal terminals arranged on the surface of the mounting substrate 2 in the peripheral area near the solid-state image sensor chip 3.

This connection is made with bonding wires.

External terminals 5 are arranged on the back surface of the mounting board 2 that is opposite to the front surface. The external terminal 5 is configured to come into contact with a terminal of a printed wiring board on the camera side to establish electrical continuity when the solid-state imaging device 1 is mounted on a camera. The external terminals 5 are electrically connected to internal terminals arranged on the surface of the mounting board 2 via wiring provided in connection holes (through holes) formed in the mounting board 2.

Each of the internal terminals and external terminals 5 is made of a metal layer such as Mo or W formed by screen printing, for example. This metal layer is formed to have a thickness of about 10 to 20 [μm]. The upper layer of this metal layer contains Ni to improve bondability.
Au plating is applied through the plating. The wiring connecting the internal terminal and the external terminal 5 is Mo at the time of screen printing, for example.

It is formed by filling the connection hole with a metal such as W.

Further, although not shown, a coating material is provided on at least the adhesive surface 2B of the surface of the mounting board 2. The coating material is formed of a ceramic material having a thickness of about 20 [μm], for example. The coating material is formed on the wiring connecting the internal terminal and the external terminal 5, and is configured to reduce the step shape caused by the wiring and flatten the surface.

In other words, the coating material is formed to enhance the adhesiveness between the mounting substrate 2 and the transparent sealing cap 4.

The transparent sealing cap 4 has a concave shape having a cavity for accommodating the solid-state image sensor chip 3. At least the uppermost part (light passage part) of the transparent sealing cap 4 is made of a transparent material because it inputs an optical signal to the light receiving surface of the solid-state image sensor chip 3.

For example, the transparent material has a transmittance of 8 for light with a wavelength of 350 to 700 [nm] on the optically effective surface where the optical signal is input.
Consists of 0 [%] or more. Further, the transparent material is made of a material that has high workability, high mechanical strength, and is inexpensive. Specifically, the transparent material is made of acrylic resin. Note that the transparent sealing cap 4 may be made of transparent glass or the like.

The transparent sealing cap 4 is fixed to the adhesive surface 2B of the mounting substrate 2 with an adhesive 6 interposed therebetween. As the adhesive 6, for example, a fast-curing liquid adhesive, specifically a glass epoxy-based ultraviolet curable resin adhesive, is used. Glass epoxy-based UV-curable resin adhesives are designed to instantly solidify when exposed to UV light.

The peripheral portion 2C1 of the surface of the mounting board 2 Specifically, a device mounting surface 7 is provided on each surface of the opposing short side portions of the mounting board 2. The device mounting surface 7 has the solid-state imaging device 1
When it is attached (mounted) to the camera frame, it is configured to come into contact with the mounting reference surface of the camera frame, and is configured to perform positioning with respect to the camera frame.

As shown in FIGS. 1, 2, and 3 (enlarged side views of main parts), the device mounting surface 7 is configured to be lower than at least the adhesive surface 2B of the surface of the mounting board 2.

This device mounting surface 7 varies depending on the size of the solid-state imaging device 2, the size of the mounting reference surface of the camera frame, the thickness of the adhesive 6, and the like. - As an example, the device mounting surface 7 may be coated with adhesive 6 for 5 minutes.
In the case of forming a film with a thickness of 0 [μm], for example, the dimension from the adhesive surface 2B to the end surface of the mounting substrate 2 is 0.3 [mml,
The height of the step with respect to the adhesive surface 2B is formed to be 0.2 [mm].

This device mounting surface 7 is prepared by transporting and mounting the transparent sealing cap 4 coated with adhesive 6 on the adhesive surface 2B of the surface of the mounting board 2 using a vacuum suction device, and then mounting it using a positioning jig. The structure is such that no adhesive 6 remains when the position of the transparent sealing cap 4 with respect to the substrate 2 is corrected. That is, as shown in FIG. 3, when the transparent sealing cap 4 is moved from the position shown by the dotted line to the position shown by the solid line using the positioning jig, the device mounting surface 7 is configured at a lower position than the adhesive surface 2B. Since it does not come into contact with the adhesive 6, the adhesive 6 is not left behind.

In this way, in the solid-state imaging device 1, by configuring the device mounting surface 7 of the surface (peripheral portion 2C) of the mounting substrate 2 to be lower than the adhesive surface 2B of the mounting substrate 2 to which the transparent sealing cap 4 is bonded. When the transparent sealing cap 4 is adhered to the surface of the mounting board 2, even if the transparent sealing cap 4 is misaligned, it is possible to prevent the adhesive 6 from adhering to the device mounting surface.

Furthermore, since the solid-state imaging bag r111 does not have any adhesive 6 remaining on the device mounting surface, it is selected as a non-defective product in the appearance defect inspection. As a result, the yield in the assembly process of the solid-state imaging device 1 can be improved.

This solid-state imaging device 1 is mounted on a lens mount frame 11 of a camera 10, as shown in FIG. 4 (a sectional view showing a schematic configuration of the camera). That is, the solid-state imaging device 1 is positioned by bringing the device mounting surface 7 of the mounting board 2 into contact with the mounting reference surface 13 of the frame 11 of the camera 10, and the external terminal 5 on the back surface of the mounting board 2 is connected to the printed wiring board. 14 terminals are connected, and the holding plate 1 is assembled with the printed wiring board 14 interposed.
It is mounted on the camera 10 by pressing with 5. The pressing force of the holding plate 15 is controlled by a screw member 16.

Further, on the front side of the mounted solid-state imaging device 1, an optical lens 12 is provided on the frame 11 of the camera 10.

The printed wiring board 14 has flexibility.

In this way, the camera 10 mounted with the solid-state imaging device 1
, the device mounting surface 7 of the mounting board 2 of the solid-state imaging device 1
By configuring so that no adhesive 6 remains, it is possible to reduce the inclination that occurs on the light-receiving surface of the solid-state image sensor chip 3, thereby reducing the misalignment between the light-receiving surface and the focal point of the optical signal of the camera 10. can be reduced. Therefore, it is possible to configure the camera 10 with highly accurate resolution.

In addition, the solid-state imaging device 1 ensures that the mounting reference surface 13 on the camera 10 side and the device mounting surface 7 of the mounting board 2 are connected reliably and stably by not leaving adhesive 6 on the device mounting surface 7 of the mounting board 2. Since they can be brought into contact with each other, mounting on the camera 10 can be performed reliably and stably.

As above, the invention made by the present inventor has been specifically explained based on the above embodiments, but the present invention is not limited to the above embodiments, and can be modified in various ways without departing from the gist thereof. Of course.

For example, the present invention provides a solid-state image sensor arranged mainly including a light receiving section in which photosensors are arranged two-dimensionally and a CCD shift register that transfers information from the photosensors arranged around at least two sides of the light receiving section. It can be applied to a solid-state imaging device having an element chip.

Furthermore, the present invention is not limited to cameras or video cameras;
The present invention can be applied to devices such as facsimile machines that use solid-state imaging devices.

Further, the present invention can be widely applied not only to solid-state imaging devices but also to semiconductor devices in which defects occur due to residual adhesive.

〔Effect of the invention〕

A brief explanation of the effects obtained by typical inventions disclosed in this application is as follows.

It is possible to prevent adhesive from remaining on the device mounting surface of the solid-state imaging device.

Furthermore, the optical accuracy of a device such as a camera in which the solid-state imaging device is mounted can be improved.

[Brief explanation of the drawing]

FIG. 1 is a plan view showing the configuration of a solid-state imaging device that is an embodiment of the present invention, FIG. 2 is a partial cross-sectional view of the solid-state imaging device, and FIG. 3 is a
FIG. 4, which is an enlarged side view of the main part of the solid-state imaging device, is a sectional view showing a schematic configuration of a camera in which the solid-state imaging device is mounted. In the figure, 1... Solid-state imaging device, 2... Mounting board, 2A
...Mounting surface, 2B...adhesive surface, 2C...periphery,
3... Solid-state image sensor chip, 4... Transparent sealing cap, 6... Adhesive, 7... Device mounting surface, 10...
Camera, 11...frame body, 13...mounting reference surface. First factor Figure 3 σ δ

Claims (1)

[Claims] 1. A device mounting surface is provided on a first portion of the surface of the mounting substrate, a solid-state image sensor chip is mounted on a second portion of the surface of the mounting substrate, and a device mounting surface is provided on a third portion of the surface of the mounting substrate. A solid-state imaging device in which a transparent sealing cap for sealing the solid-state imaging element chip is bonded to a portion with an adhesive, wherein the device mounting surface, which is a first portion of the surface of the mounting substrate, is attached to the transparent sealing cap. A solid-state imaging device characterized by being configured to be lower than a third portion of the surface of a mounting substrate to be bonded. 2. The solid-state imaging device according to claim 1, wherein the adhesive is an ultraviolet curing liquid adhesive.