JPS63119372A - Solid-state image pickup device - Google Patents

Abstract

PURPOSE:To obtain a picture characteristic with high resolution by selecting an agle between the adhered face and the element face of a connection section of each solid-state image pickup element to a specific value of above so as to prevent the distortion of a picture of the connection section. CONSTITUTION:The shape of a connected face of a solid-state image pickup element 1 is selected so as to have an angle between the element face and the connecting face as (90 deg.-maximum incident angle thetaM of light) of above and the face is connected to have a wedge shape space. Thus, the light incidence at the connection part is prevented from the transparent substrate 1 toward an adhesives 2 with respect to the connection face of the solid-state image pickup device. The confinement of light in the adhesives is mitigated in the relation of nA>nB and the incidence from the transparent substrate 1 to the adhesives is avoided in case of nA<nB, where nA is the refractive index of the adhesives 2 and nB is the refractive index of the transparent substrate 1. Thus, the intensive reflecting face of light is eliminated and the reduction in the resolution of a picture due to the interference of the picture near the connection part due to the reflection of light at the connection part is improved remarkably.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a mounting structure of a solid-state imaging device in which a plurality of solid-state imaging devices are arranged using a transparent substrate and light is incident from the back surface of the device.

[Conventional technology]

Currently, in applied fields such as facsimile, the usefulness of solid-state imaging devices that can handle document widths is attracting attention because of their compact and economical image reading units. In particular, by forming the scanning circuit that drives the light-receiving element of the solid-state imaging device in the same chip, the solid-state imaging device becomes highly reliable and economical with a small number of lead-out wires to the outside.

However, it is extremely difficult to form a solid-state imaging device with the width of a document using current semiconductor devices.

Therefore, a document-width solid-state imaging device made by arranging a plurality of solid-state imaging devices has been considered, but there are many unresolved problems regarding the arrangement accuracy and method of arrangement.

In particular, in conventional solid-state imaging devices that use a transparent substrate and allow light to enter from the back side of the element, the connection part is made by using adhesive on the connection surface cut perpendicular to the element surface, as shown in Figure 3. It was formed by filling.

[Problem that the invention seeks to solve]

However, with conventional technology, the difference in refractive index between the adhesive and the transparent substrate causes a phenomenon in which light incident on the light-receiving element near the connection part is refracted, resulting in a problem in that resolution near the connection part deteriorates. . In other words, the refractive index of the adhesive is
If the refractive index of the transparent substrate is rLB, nh>3m
At this time, the adhesive on the connection surface becomes a fiber against the transparent substrate, and light is trapped in the adhesive. (Figure 3 (
α)) When f&A<3B, the adhesive becomes a reflective surface with respect to the transparent substrate. (Figure 3(b)) Furthermore, since the connection surface is cut perpendicular to the element surface, the connection is surface contact, so it is extremely difficult to reduce the unevenness of the connection surface to the micron order, and it is difficult to There was a problem in that the placement accuracy deteriorated and image distortion occurred.

Therefore, the present invention is intended to solve these problems.
The purpose of this is to precisely arrange the spacing between the elements at the connection part and achieve high-resolution image characteristics in a solid-state imaging device that uses a transparent substrate and has a plurality of solid-state imaging elements arranged to receive light from the back side of the element. The objective is to provide a highly reliable mounting structure with

[Means for solving problems]

In a solid-state imaging device in which a plurality of solid-state imaging devices are arranged using a transparent substrate and light enters from the back side of the device, the angle between the adhesive surface of the connection part of each solid-state imaging device and the device surface is (9
0'-maximum incident angle of light) or more.

〔Example〕

Hereinafter, the present invention will be described in detail based on examples.

FIG. 1 is a sectional view of a connecting portion of two arranged solid-state imaging devices of the present invention. In this figure, pixels A, 4 and pixels B, 5 are spaced apart from each other on the same chip (number of pixels is 16).
In the dot/IIm device, the spacing must be the same as 6'L (5 μm). In other words, if the width of each element is 50 μm, it is necessary to connect the device ends with a width of 1″L5μ.Furthermore, in the case of a solid-state imaging device that uses a transparent substrate and enters light from the back side of the element, In order to prevent diffused reflection of light on the connection surface, it is necessary to fill the connection portion with an adhesive whose refractive index is equivalent to that of the transparent substrate.Here, in the present invention, the shape of the connection surface is shown in FIG. As shown in , the angle between the element surface and the connection surface is (906-maximum incident angle of light θM
), they will be connected with a wedge-shaped space. As a result, the incidence of light at the connection part is
It is possible to prevent light from entering the adhesive from the transparent substrate side with respect to the connection surface of the solid-state imaging device. In particular, if the refractive index of the adhesive is nA and the refractive index of the transparent substrate is rLB, then r&A
>nB, the light is not confined in the adhesive, and when A<rLB, the light does not enter the adhesive from the transparent substrate side as described above, so the light is strongly reflected by the surface. It can be eliminated.

In this way, if the refractive index of the adhesive or transparent substrate differs due to manufacturing quality, etc., the connection due to light reflection at the connection part will be more difficult than the conventional connection surface perpendicular to the element surface. It is possible to significantly improve the reduction in image resolution due to image interference in the vicinity of the area.

Furthermore, since the connection surface has a wedge-like shape for connection, the connection of the solid-state image sensor is a line contact, so the unevenness of the connection surface does not affect the connection, and the arrangement accuracy is improved. However, since it is a line contact as mentioned above, chipping of the element at the contact surface may be a problem, but the connection surface of the solid-state image sensor is fixed to a certain extent as shown in Figure 2 so as not to affect the image. By using a surface contact type, it is possible to prevent the transparent substrate of the solid-state imaging device from chipping, and it is possible to form a reliable high-resolution solid-state imaging device.

〔Effect of the invention〕

As described above, according to the present invention, in a solid-state imaging device in which a plurality of solid-state imaging devices are arranged using a transparent substrate and light is incident from the back surface of the device, the bonding surface of the connecting portion of each solid-state imaging device and the By setting the angle between the surfaces to be equal to or greater than (90°-maximum incident angle), it is possible to sufficiently moderate the reflection or confinement phenomenon of light at the connection portion caused by the difference in refractive index between the transparent substrate and the adhesive. Therefore, distortion of the image of the connection part can be prevented,
This has the effect that high-resolution image characteristics can be obtained. As a result, it is possible to easily form an economical solid-state imaging device that accommodates a wide original.

Furthermore, since the shape between the connecting parts forms a wedge-shaped gap, the contact surface between the elements becomes a line contact, eliminating the effect of unevenness on the connecting surface on the connection accuracy, and significantly improving the pixel σ spacing accuracy. , it is possible to obtain image characteristics without deviation of the connection part. Additionally, since the bonding strength with the adhesive increases due to the increase in the area of the connecting surface, it has the remarkable effect that a highly reliable solid-state imaging device that is resistant to stress can be obtained.

[Brief explanation of the drawing]

1 and 2 are cross-sectional views of the connecting portion of the solid-state imaging device of the present invention, and FIGS. 5(α) and (b) are cross-sectional views of the connecting portion of the conventional solid-state imaging device, and (α) (b) shows the incident path of light depending on the difference in refractive index between the adhesive and the transparent substrate. 1...Solid-state image sensor 2...Adhesive 3...Fixed substrate 4...Pixel 5...Pixel B1 6... ... Maximum incident angle of light 0M or more Applicant Seiko Epson Corporation Figure 1 Figure 2 Figure 31! ! (G) Figure 3

Claims (1)

[Claims] In a solid-state imaging device in which a plurality of solid-state imaging devices are arranged using a transparent substrate and light enters from the back surface of the device, the angle between the connection surface of the connection portion of each solid-state imaging device and the device surface is (
90°-maximum incident angle of light) or more.