JPS58195356A - Adhesion type image sensor - Google Patents

Abstract

PURPOSE:To improve resolution, by providing a light shielding layer having an opening section correpsonding to each photoconductor element one to one. CONSTITUTION:A transparent electrode 32 made of ITO or SnO2 is formed on a transparent insulation substrate 31 in stripe shape, a light shielding layer 33 made of Cr or the like is formed on the electrode 32 with the vapor-deposition or sputtering, and the photoconductor element only is etched, allowing to form a window made of Cr at the photoconductor element. One side of the Cr film is taken as a common electrode. Further, a photoconductor material 34 is grown to form an individual electrode 35 made of Al or the like, allowing to form the photoconductor element with the photolithography technology so that the electrode corresponds to the Cr window by one to one. A reflected light 36 contacts the element of the electrode 35 at the window of the shield layer 33 only. Even if only one signal receives a dark signal and the rest elements receive a light signal, since the part among all the elements is covered with the light shielding layer, the leakage current from adjacent elements is almost negligible.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention provides a facsimile transmitter for transmitting a document and a v.
Close-contact type photoelectric conversion device that performs IT transfer by attaching 1i
This is related to f + jK.

Recently, in a charging conversion device for a 7mm transmitter, as shown in Fig. 1, a plurality of solid-state light source arrays such as LEDs are used as light sources to illuminate the document 2, and this reflected light is used as a light source. For example, using a plurality of self-focusing lens arrays 3 (for example, SELFOC lens array manufactured by Nippon Sheet Glass Co., Ltd., hereinafter simply referred to as "Shi-nzu array"),
There is a method of condensing light onto a plurality of photoconductor elements 4 and removing the information on the two sides of the original. When this method is used, it comes into close contact with the two sides of the original, creating a one-to-one image sensor, unlike conventional MOf9, αC, D)! The long optical path length of the optical system required in the charging conversion device using the sensor 1 is not required, and there is an advantage that the device can be miniaturized.

Photoconductor materials used in such contact type image cells include + Cd8-Cd8ea 8e-As -
Te.

Single crystal 8i amorphous St, etc. are used.

Normally, such photoconductor element lines 8 are grown on the brightest insulating substrate, such as a glass plate, and then separated into dots by photolithography to form a one-dimensional array. However, depending on the photoconductor material, photolithography technology @2
For example, when using hydrofluoric acid-based etching liquid),
When a glass-based substrate as described above is used, this substrate may be adversely affected. In addition, not using such a method can simplify one process and lead to one-step bacteria reduction. From this.

During growth, the photoconductor element is formed into stripes.

It is easier to separate the jars into dots than the drawer 1C, and it is also possible to draw them out alternately depending on the case.
Therefore, it is also advantageous for high-density wiring.

An example of an image sensor configured in such a striped shape is shown in FIG. 2(a).

There is a so-called side innote structure in which the leading conductor material 204 is sandwiched between a common electrode 21 and individual electrodes 22 to form each element in the thickness direction of the photoconductor material 20.

FIG. 2(b) shows a cross-sectional view taken along line A-A' in FIG. 2(a) in the direction of the arrow. However, when using an image sensor with such a lintoituna structure,
If the reflected light from the original M4rM or the pattern of light after passing through the lens array is incident on other photoconductor elements and between the elements, except for example the second photoconductor element,
@Excluding the second photoconductor element part, the resistivity of the photoconductor element in the latter part and the film between the elements decreases, and a current flows between the upper and lower electrodes. Since the open resistivity of the element on both sides of the second photoconductor element is lowered, the leakage current also tends to flow through the second photoconductor element. Therefore, the second photoconductor element exhibits a value slightly larger than the dark signal level.

As described above, when an image sensor with a conventional striped photoconductor is used in a photoelectric conversion device,
Deterioration of resolution in the main scanning direction has been a major problem.

An object of the present invention is to provide a contact type image sensor that solves these drawbacks.

According to the present invention, a plurality of separate individual electrodes and a transparent electrode are placed on an insulating substrate to extract an output signal according to the brightness or darkness of incident light across a strip-shaped photoconductor.・
, an over-electrode, and a light continuous layer having an opening corresponding to each photoconductor element Kl and IK formed between each of the plurality of individual electrodes and the common electrode. A secret document type image sensor is obtained.

Embodiments of the present invention will be described below with reference to the drawings. FIG. 3 shows an embodiment of the present invention. For example, a transparent insulating substrate 3 such as a glass plate
A transparent electrode 32 made of ITO or 8 n O, etc. is formed in a stripe shape by evaporation or photolithography on L, and a light-transmitting layer 33 made of Cr is vapor-deposited or made by photolithography. When only the photoconductor element portion is etched using the 7-otolithography technique, a Cr window is created in the photoconductor element portion.One side of this Cr film is used as a common electrode terminal.After this, the photoconductor material 34 is etched using the photoconductor element portion. Let it grow.

Finally, individual electrodes 35 made of e.g. ^e are formed by vapor deposition or sputtering, and then by photolithography.

By configuring the photoconductor elements so as to correspond to 1:IK in each of the window portions of the mountain, a close-contact type image sensor with 1:1K is achieved.

Next, the operating principle of this image sensor will be described below. First, reflected light 36 from the original tA surface enters the substrate from where no sensor is mounted. This reflected light 36 hits only the photoconductor 35 element portion in the window portion of the C4 light shielding layer 33, and the photoconductor 35 element exhibits photoconductive properties depending on the brightness of this reflected light 36. However, as mentioned above, even if only the second photoconductor element is a dark signal and the remaining photoconductor elements are all bright signals, the space between all the elements is covered with a transparent layer of +Cr. Therefore, even if light is incident on this portion, the resistivity of the photoconductor 35 between the elements does not decrease.

Therefore, the leakage current from the first and third photoconductor elements on both sides can be ignored, and the leakage current from the second photoconductor element is almost negligible.
The th photoconductor element can maintain one level of dark signal. This increases the level difference between so-called bright and dark signals, which improves resolution.

Figure 4 (a) is a view of Jin's contact image sensor from above;
It is a sectional view between A'. In FIG. 4, the substrate 40 may be an insulating substrate, whether it is a transparent substrate made of the glass plate IK mentioned above or a substrate made of alumina or the like.

On this substrate 40, first) individual electrodes 35 having a 1st scale surface are formed by vapor deposition or sputtering, and then photo-etched into a predetermined pattern.

A photoconductor 34 is grown on this, and then 1. T,
A trend electrode 32 made of 0, SnO, and Cr, and a light shielding layer 33 made of Cr, etc. are formed by vapor deposition or sputtering. It is necessary to have a window. With such a configuration, the reflected light 36 from the document surface.

Since the light enters from above the sensor surface of the substrate 40, the substrate 40 does not need to be a particularly transparent substrate, and the p! High sensitivity may cause characteristic deterioration due to dust etc.

High resolution is achieved. Furthermore, the configuration example shown in FIG. 4 is operationally the same as the configuration example shown in FIG. 3, and it is clear that the same improvement in resolution can be expected. In addition, in the embodiment of the present invention, the Qlil separate electrodes are drawn out only in all electrode directions, but the invention is not limited to this.
You can also pull it out. In this case, the wiring density of the electrodes is halved, which improves manufacturing yields and is also advantageous for high-density wiring.

As described above, as shown in the present invention, if a light shielding layer of Cr or the like is provided for each focus, the resolution of the image sensor can be improved. Also.

Such a light-shielding layer is sometimes used to determine the original conductive system element in the scanning direction, and at this time, it is used for each bit at the same time! Since it is easy to provide tζ, it is not necessary to increase the steps of vapor deposition and sputtering compared to the conventional contact type image sensor. Furthermore, by eliminating the photolithography process of separating the photoconductor into individual elements, one process is simplified, and the 9-yield direction -EK is also connected.

[Brief explanation of drawings]

Figure 1 shows an example of a photoelectric conversion device. It is. 2(a) and 2(b) show a conventional example of a contact type image sensor, 20 is a photoconductor element, and 21 is a common electrode. 22 is an individual electrode, and 23 is a substrate. 3 and 4 (a) and (b) are examples of actual noodles according to the present invention, 31 is a transparent insulating substrate, 32 is a Fi transparent electrode, 33 is a light shielding layer, 34 is a photoconductor, 35t is an individual electrode,
Reference numeral 36 indicates reflected light from the surface of the document, and reference numeral 40 indicates an insulating substrate. Fig. 1 Fig. 2 C′ (ν) 1 bow Z Fig. 3

Claims (1)

[Claims] On an insulating substrate, there is a @-shaped photoconductor, and a common electrode consisting of a plurality of separate individual electrodes and transparent electrodes for outputting output signals depending on the brightness and darkness of the incident light across the photoconductor. electrodes, and each leading electric body volume IIC1 and IK constituted between each of the individual electrodes separated into the plurality of pieces and the common electrode.
A contact image sensor characterized by being provided with a light shielding layer having a corresponding mouth portion.