JPS5887862A - Long-sized one-dimensional thin film sensor - Google Patents

Abstract

PURPOSE:To suppress the variation in the sensor area of each bit as well as to eliminate the non-uniformity of the voltage applied to the sensing part of the titled sensor by a method wherein the transparency-deteriorated edge part of a narrow-stripped transparent electrode is coated by a non-light-transmitting metal film, and voltage is applied to the transparent electrode through said non-light-transmitting metal film. CONSTITUTION:On a glass substrate 1, a lower metal electrode 2 is formed with its sensing part formed in a longtudinally long rectangle. An optical semiconductor thin film 3, consisting of a non-amorphous or polycrystalline semiconductor, is coated on the electrode 2. Besides, on the above electrode 2, a narrow-stripped transparent electrode 4 of almost the same width as that of the lower metal electrode in longitudinal direction is provided. On the top of the above, a non-light-transmitting metal thin film 5 is formed in such a manner that the film 5 is covering the low light-transmitting edge part located at both ends of the narrow-stripped transparent electrode 4. Both of the left and right ends of said non-light-transmitting metal thin film 5 are connected to the voltage supplying source terminal (not shown in the diagram) which supplies voltage to the narrow-stripped transparent electrode 4. Voltage is applied to the narrow-stripped transparent electrode 4 by the metal thin film 5, and bias voltage is applied to an optical semiconductor thin film 3 located between electrodes 2 and 4. Accordingly, electric charge can be stored in the thin film 3.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a long-dimensional thin film sensor using a thin film semiconductor, and in particular, the edge portion of a band-shaped transparent electrode where the light transmittance is reduced is nuclided with a non-light transmitting metal film, and this non-transparent metal film is used as a nuclide. The present invention relates to a long-dimensional thin film sensor in which a voltage is applied to a transparent electrode through a transparent metal film.

Light-receiving elements using thin-film semiconductors are easy to increase in area, so
It is promising as a compact image sensor that is in close contact with the document. Sensor structures include a sandwich type in which a thin film semiconductor is narrowed between upper and lower electrodes, and a planar type in which a thin film semiconductor is narrowed from both sides. Among these, the sandwich type is more advantageous in terms of photoresponsiveness because the thickness of the thin film semiconductor can be made thinner.

Figure 1 shows a plan view of this sandwich type sensor, and Figure 2 shows a sectional view taken along line A-A' in Figure 1. In FIG. 1-2, 1 is a caballas substrate, 2 is a lower metal electrode, 3 is an optical semiconductor thin film, and 4 is a band-shaped transparent electrode.

With this conventional sensor groove structure, when increasing the bit density and increasing the length, there were two problems as described below.

(1) Translucency is poor at the edge portion a in the longitudinal direction of the band-shaped transparent electrode 4, and overetching is observed in the peripheral portion of the hollow metal electrode 2. This etching is particularly noticeable at the four corners. Therefore, the moving area of the sensor is reduced, and the spread of the sensor performance for each bit is increased.

(2 Emperor Transparent Tortoise & 40) As the width becomes narrower, the resistance value of the band-shaped transparent electrode increases and the voltage applied to the sensor section becomes non-uniform.

The purpose of the present invention is to eliminate the drawbacks of the conventional thin film sensor described above, and to create a long-dimensional thin film sensor f1 in which the voltage applied to the sensor part is uniform without variations in each bit. It's about doing.

The % characteristic of the present invention is that the edge portions of the width direction ends of the band-shaped transparent electrodes where the translucency has decreased are covered with a non-J six-light permanent gold maple film, and only the edge portions of the core band-shaped transparent electrodes with good translucency are covered. By using JJI l as a sensor part, the variation in sensor surface performance of the pit is kept small, and by applying a voltage to the transparent electrode with high resistivity through the non-transparent gold film, (The non-uniformity of torque L1- applied to the sensor part)
IJ) It is at the erased point.

The present invention will be described below by way of an embodiment. A plan view of a sensor structure according to an embodiment of the present invention is shown in FIG.
Cutting [Figure 1 into Figure 4 7J<D.Glass substrate 1 (])
A lower metal electrode 2 is formed on the top so that its sensor portion has a vertically long rectangular shape. Moreover, an optical semiconductor thin film 3 made of an amorphous or polycrystalline semiconductor is formed as a thin film 8.

A band-shaped transparent electrode 4 is provided in a band-like manner with a width approximately equal to the vertical width of the lower metal electrode. -Sales 1
This is formed so as to cover the edges with poor translucency at both ends of the non-transparent metal membrane 5 or the transparent electrode 4. Both left and right ends of the fine thin film 5 are band-shaped J.
h is connected to a voltage supply source terminal (not shown) to the bright electrode 4;

Next, an example of the manufacturing method of this embodiment described above will be explained.

This manufacturing method uses A1 as the lower metal electrode 2, amorphous silicon as the optical semiconductor thin film 3, an oxide of in/tsum and tin as the band-shaped transparent electrode 4, and a non-transparent metal film 5 as the uppermost layer. This is an example when Al is used.

First, an Al'z film is deposited on a glass substrate 1 to a thickness of about 3 uOm by electron beam evaporation. Subsequently, an electrode pattern for the sensor section and its leads is formed by photolithography to form the lower metal electrode 2.

At that time, the sensor part should be made into a vertically long rectangle with a width of l* (about 1.5 times the vertical width. For example, when making a sensor with 8 Kaitoge summers/rhyme, the sensor part should be Vertical, X is 15
It is preferable to set the width to 0 μm and the width to be 100/Jm.

Next, in order to form an optical semiconductor thin film 3, hydrogenated amorphous silicon is deposited to a thickness of about 1 μm by a glow discharge method. For the creation, use 109% S+H, Rli'Pa'
7-2O-50W, gas flow i20-50SCCM, pressure 0.4-0.6 Torr, substrate sea level 200-30
0-C, a distance between the electrode plates of 40+m, and a curved glow release for 30 minutes to 1 hour.

Next, ITO (10 molar In2L) of the band-shaped transparent electrode 4 was added.
) g + 90 7iv%Sn 02 ) 'i: D
A film is deposited to a thickness of about 5ooX by C-shatta')7. Sputtering conditions: Pa'7-170-250
W#l! Cumulative pressure 15X 10' Torr + total pressure (
Sputtering is carried out for about 10 minutes at 4 x 10" Torr (all indenter argon). The band-shaped transparent electrode 4 is deposited using a metal masker. to form.

Finally, a non-transparent gold film is deposited to a thickness of approximately 3000 mm by electron beam evaporation using Alk. At this time,
The chest had a cap of 50 .mu.m so as to extend 25 .mu.m in the longitudinal direction of the lower metal electrode 2. This 7-luminium thin film may be formed by using a metal mask, or by forming a pattern by photolithography after depositing At on the entire surface of the sensor portion. The latter name is more accurate or requires more steps.

Above θ) Bujf1. : It is possible to form a long-dimensional thin film using -C.

Next, a description will be given of the operation of the long-dimension and thin-dimension sensor U) according to this embodiment.

A voltage is applied to the metal thin film 5 (to the band-shaped transparent electrode 4 and the lower metal electrode 2).A bias voltage is then applied to the optical semiconductor thin film 3 between the band-shaped transparent electrode 4 and the lower metal electrode 2. As a result, charges are accumulated in the optical semiconductor thin film 3.

A light image is irradiated from an optical device (not shown) onto each Sanderutsch-shaped light receiving element to which a bias voltage is applied in this manner. Then, the charge accumulated in the above-described manner from the light-receiving element hit by the light is neutralized and disappears within the light-receiving element. On the other hand, accumulated charges remain in the light-receiving element in areas not exposed to light. In this way, the 'wIL direction pattern formed in the thin film sensor according to the photons is formed on the lower metal electrode 2.
Each beat is read by an unspecified swinging cow step connected to the lead. Therefore, by employing the above-described configuration, the optical image of the present invention can achieve the following effects.

(1) The voltage applied to each light-receiving element can be kept constant at θ), which reduces the variation in effective bending loss of the sensor by about 10
It is possible to reduce the percentage from 5% to less than 5%.

This can significantly reduce errors during reading.

(2) Since it is possible to supply a voltage to the pole of the strip-shaped transparent electrode by means of the non-transparent metal film formed in the pitch direction at the end of the strip-shaped transparent electrode, the thickness of the strip-shaped transparent electrode can be reduced from 1500 to 500. You can give it some time.

Therefore, the light transmittance can be increased from the conventional approximately 85φ to 90 or more, and the transmission of irradiated light can be reduced.

[Brief explanation of drawings]

FIG. 1 is a plan view of a conventional sandwich type sensor, FIG. 2 is a 1-LIT curve diagram of the AA' gland in FIG. 1, FIG. 3 is a plan view of an embodiment of the present invention, and FIG. A sectional view taken along the line A-λ in the figure is shown. 1. Glass substrate, 2. Lower metal electrode, 3. Optical semiconductor thin film, 4. Band-shaped transparent 11L pole, 5. Non-transparent metal film Patent attorney Michi Hiraki (1 non-person) Figure 1 Figure 2

Claims (1)

[Scope of Claims] (1) A substrate, a lower metal electrode forming a sensor section and a lead formed on the substrate in a plurality of parts, and a light provided so as to cover the plurality of lower metal m-poles. A semiconductor thin film, and at least the plurality of lower metals 1 on the optical semiconductor thin film! In this case, the long-dimensional thin film sensor having a strip-shaped transparent electrode provided in a portion facing the pole, the strip-shaped transparent electrode 8A11.
A long-dimensional thin film sensor characterized by a black color with a non-transparent metal thin film provided at one end of the i-pole. (2) A patented thin film sensor characterized in that a bias voltage is applied between the band-shaped transparent electrode and the lower metal electrode by a voltage applied from a non-light-transmitting thin film. (3 ) The non-light-transmitting metal thin film is provided at both ends in the width direction of the band-shaped transparent electrode. Thin film sensor.