JPS59138371A - Photo sensor array - Google Patents

Abstract

PURPOSE:To obtain a sensor array of a high yield and a low cost by a method wherein a common electrode is composed of a discrete electrode of a photo sensor element and one electrode of a capacitor, and a light shielding member corresponding to the photoconductive layer other than the photoelectric conversion part of the element is composed of this common electrode and the other electrode of the capacitor. CONSTITUTION:A semiconductor layer 2-2 is adhered on a glass substrate 2-1, thus forming it into a photo sensor, and the charge accumulating capacitor not illustrated is formed on the same substrate. Next, ohmic contact layers 2-3 are formed on said layer 2-2 at an interval, and the common electrode 2-4-a is adhered on one layer thereof, and the discrete electrode 2-4b on the other layer, respectively. Thereafter, the entire surface is covered with an insulation layer 2-5, and the capacitor common electrode 2-6 is formed on said film by corresponding to the discrete electrode 2-4-b. Thus, the electrode 2-6 is made to serve as the light shielding member for said layer 2-2 other than the photoelectric conversion part.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field] The present invention relates to a photosensor array for extracting optical signals.

[Prior art]

Conventional 1 For example, as an ft5ti conversion means that constitutes a reading section of a facsimile machine, digital copier, etc.

One-dimensional photosensor arrays of the silicon photodiode type are generally known. However, in the silicon photodiode type one-dimensional photosensor array mentioned above, 5
Because there is a limit to the size of a silicon single crystal that can explode, it has been difficult to create a long photosensor array.

Therefore, JJiE+ = Is it necessary to optically reduce the value?

There was a disadvantage in trying to miniaturize the device.

On the other hand, in recent years, the length has been increased by film forming methods such as glow discharge, sputtering method, ion blating method, vacuum evaporation method, and method of applying a mixture of binding side fat and semiconductor phase material. , large area G).

Methods for driving an elongated photosensor array include a signal processing method using a combination of a switching transistor and a shift register, as disclosed in Japanese Patent Application Laid-Open No. 56-1318 for 1+11E, and a signal processing method using a combination of a switching transistor and a shift register, as disclosed in Japanese Patent Application Laid-Open No. 56-138359. switching transistor and B B D (Bucket
A signal processing method based on Brigade Device (Brigade Device) is adopted, but in the methods described in both publications, capacitors for charge storage are connected to individual photosensor elements forming one stroke Y4R. The load storage capacitor requires a capacitance of about 100 pF', for example. Therefore, the above 1! Therefore, it is difficult to form the storage capacitor within the driving IC chip of the photosensor array.

Generally on the same base as the photosensor array! # Forming a storage agent capacitor is performed.

One conventional photosensor array will be described using FIGS. 1(al) to 1(cli).

Figure 1 (8) is a partial plan view of a conventional photosensor array having a capacitor for inspection. Figure 1 (at
Figure 1(a) is cut at 3', 4% dXX', YY', and is a cut-out section of a raised chivalrous style.

X 1 [1 (at to 1st section 1 (C), 1-1
．． 1-2, 1 3.1 4-a, 1-4-b, respectively, in order of base & 9 conductive layers, J--mic contact layer.

Showing the common deterioration of photosensors and the individual concerns common to photosensors and charge storage capacitors・1-5.1-
6 is the insulating layer constituting the capacitor, and the 1σ1 co-tracing l pole, respectively.
4-b Since the photoelectric layer 1-2 also exists in iHl, the source of the photoelectric layer 1-2 between the individual i-tei 1-4-b is the original one, which is also the archetype and the convection part. In addition to the original Genryu Henkyaku Club, a wasteful former #R Hendai Club has been created, resulting in C6. This ink also causes a problem of inflow of photocurrent which causes noise due to one-dimensional irradiation, and is said to be the cause of deterioration of the cumulative characteristics such as noise.

Therefore, it becomes necessary to provide a receding film so that the light does not hit unnecessary areas with respect to the direction of light incidence. For this reason, in the case of conventional photosensor arrays such as those shown in Figures 1(a) to 1(C1), optical elements such as metal are used to guide the light in unnecessary areas. It is necessary to concatenate the I layer.

Historically, in conventional photosensor arrays.

In order to protect the original light 11i changing portion from the external environment and mechanical impact, an additional process for providing a passivation film is required.

〔the purpose〕

The present invention has been made in view of the above points, and the present invention has been made in view of the above points.
It is an object of the present invention to provide a photosensor array that can be formed without increasing the number of manufacturing steps of the photosensor array.

Another object of the present invention is to provide a photosensor array that can be formed without increasing the number of manufacturing steps required for the passivation IMI photosensor array in the main power exchange section of the photosensor array.

In the photosensor array of the present invention, the individual electrodes of the photosensor element and one electrode of the capacitor have a common single pole and a hole, and at least one of the cooperating electrode and the other 14L pole of the capacitor One feature is that Km is a continuous light member of the optical 4-electronic shield other than the i-electronic conversion section of the photosensor element. Further, the photosensor array of the present invention is characterized in that the insulating film of the charge storage capacitor is used in the pad hasion film of the photoelectric conversion section. At least one of the °a poles v h Motobe Kiri,
By using a high-grade passivation film as the loquat film of the capacitor, the above objects can be achieved without increasing the number of steps.

Further disadvantages: 1. The photosensor array of the present invention can be provided with a light shielding member and a passivation film without increasing the number of steps, resulting in a high yield and low cost.

Furthermore, if the charge storage capacitor is formed by laminating it on the individual electrodes of the photosensor, a smaller photosensor array can be provided.

〔Example〕

The present invention will be explained below using examples.

Figure 2 (al is a schematic plan view for explaining one preferred embodiment of the present invention. Figure 2 (bl and Figure 2) is a schematic plan view for explaining one preferred embodiment of the present invention.
cl is the dashed dotted line XX'J shown in Figure 1 (a), respectively.
FIG. 2 is a schematic cross-sectional partial view when cut at YY'.

In this second embodiment, the optical guiding layer will be explained using a system made of amorphous silicon containing at least one of hydrogen and halogen elements.

Of course, the light guiding layer is other than amorphous silicon.

For example, Ods, Cd-Te, a-Se, a
A thin film or a thick film of -Se-Te (the above a indicates amorphous) or the like may be used.

First, 8iH4 scum diluted to 10 volume% with fk, Hs, which was kept at 300°C, was heated at a gas pressure of 0.50 Torr and RF (
Radio Frequency) 0.7 by performing the glow discharge method for 2 hours at a power of 10W.
A μ-thick silicon film was formed.

Next, Il Q vnlume % was changed n, and S
Using gas with a flow ratio of 100:1 between iH4 gas and pH scum diluted to 1100 pp in the city as raw materials, a 01 μ thick n+j*, ν0, and ohmi 11. Kukontaku, increased and formed ◇ history +
WB (Electron Beam) After Mn is packed with a thickness of 0.1μ using the g column method, it is packed in a hoji type AZ-1370.
A photoresist pattern is formed into the desired shape using photoresist (product name: 5hipley).

11p (R5vnlume% water bath), aP<
Wei (60vnlum%Zk @M'), ice me
In (1), the AZ-1370 photoresist was removed, and the common room Q2-4''-a and the individual ゛1IL42- 4-
b. The light-receiving part, that is, the original [transformation part] was formed.

Next, using the glow discharge method, I Q vnlum with H snow
8iHa diluted to 5800 M O-1 at a flow rate of 5800 M O-1.

NHs was flowed into the device at a flow rate of 2080 CM.

By glow discharging for about 2.5 hours under the condition of RF power 10W, the silicon nitride insulation layer 2-5 is formed.
The stones were deposited 0.4μ thick.

Then, Or was deposited using BB evaporation.

The common t-pole 2-6 of the load storage capacitor σ) was formed in the same manner as the common chamber 72-4-ai individual electrode 2-4-b.

The photosensor array of this example was fabricated in the manner described above.

In this embodiment, the photosensor array was fabricated so that the electrode width L was 3100 μm and the width S between adjacent electrodes was 25 μm.

In addition, the common electric body 2-6 of the charge storage capacitor is 1 width 7
The end face of the electric sliding door 2-6 on the side of the converter section was formed about 10 μm apart from the end face of the photoelectric converter section which is the most individual converter side.

In this example, -C, *miscellaneous 2-6 and one direction electrode 2-4-
The capacitance per photosensor element of the charge accumulation capacitor formed by sandwiching the capacitor with silicon in b is suppressed.

The valley t was approximately 100 pF.

In this embodiment 91.1, when light is incident from the opposite side of the glass substrate, the t-pole 2-6 of the charge storage capacitor is used to create a photoconductor layer in the weak part of the photosensor array. Since the light is not irradiated on the 24 electric layer of the stone, there is no 1
It is possible to obtain a photosensor array in which the flow of the original current is blocked, there is no noise, and the resolution is improved.

A photosensor array having a configuration similar to that of this example without the badge bay/con film of the photoelectric conversion section, that is,
An original conversion part without silicon nitride was prepared, and the catalytic aging was compared with that of the present example with a passivation film.

FIG. 3 is a diagram showing changes in photocurrent values over time with and without a passivation film, with the former being represented by curve a and the latter by curve mb. .

As shown in Figure 3, when there is a passivation film in the photoelectric conversion section, the deterioration of the device is so small that it can be ignored, and when compared with the deterioration when there is no passivation film, n is A positive effect was observed.

In this embodiment, the passivation film is made of silicon nitride and has holes, but of course this is because the absorption of light in the visible light range is extremely small.

Generally speaking, it does not have a negative effect on light in the visible range 1d, which is safe for facsimiles and the like.

The passivation film can be applied to the device and is suitable as an insulating layer for a capacitor for electrode cans, and furthermore, it is important that this embodiment does not have any negative impact on the original information. Materials other than silicon nitride used in can also be used. ft of the common polarity of the charge storage capacitor, the end on the electric conversion section side is approximately 10μ apart from the end of the photoelectric conversion section that is closest to the individual polarity. However, the position where the common electrode is formed is not limited by this value. The common electrode or the photoelectric conversion part must be formed at a distance of 4λ to block the minimum necessary source information, or be formed so far away from the photoelectric conversion part that it is unnecessary and cannot fulfill the role of continuous light to the photoconductive layer. That's fine. In this embodiment, since it is difficult to make the end faces completely coincident over the entire length of a long sensor array, the sensor array is formed in the shape of jOμ in order to absorb some positional fluctuations.

A charge storage capacitor having a desired capacity can be arbitrarily set by appropriately selecting the Al type and thickness of the insulating layer of the capacitor, and the width and length of the electrodes that sandwich the insulating layer. Other embodiments will be described using figures.

Figures 4 (at to 4 (cl) are photosensor arrays of the type in which charge storage capacitors are stacked on individual electrodes of the photosensor elements, and the photoconductive layer between the individual electrodes is removed. FIG. 3 is a schematic plan view and a schematic cross-sectional view of one of the sensor arrays.

The photoconductive layer other than the photoelectric conversion part is shielded from light by the individual electrodes 4-4-b and the electrode 4-6, and the insulating layer 4-5 of the capacitor
also serves as a passivation film.

Figure 5 (al to Figure 5 (d) 1 Figure 6 (at to Figure 6)
Figure (d) G1 each, 1! FIG. 3 is a diagram illustrating a type of photosensor array in which load storage capacitors are not stacked on individual electrodes of photosensor elements.

Figure 5 (al to Figure 5 (d) shows the case where no passivation is applied, and Figure 6 (al to Figure 6 (dl) shows the case where the insulating layer of the charge storage capacitor and the passivation film are the same. This is the case when it is made up of parts.

5(a) and 6(a) are schematic plan partial views, FIG. 5(bl to 5(al) and FIG. 6(bl to 6)
Figures dl and dl are schematic cross-sectional partial views taken along dashed lines xx', YY', and ZZ' shown in Figure 5 (al) and Figure 6 (al), respectively.

〔effect〕

As described above in detail, a photosensor array having the structure of the present invention has a structure that is formed continuously with at least one of the electrodes of the charge storage capacitor. Since at least a portion of the pole serves as a light shielding member for the photoconductive layer, there is no need to form a new light shielding member.

Also, when applying a passivation film, by using the insulating layer that forms the capacitor as it is, even if you perform the process of applying the passivation film again in this case, the passivation film can be removed only in the process of forming the capacitor. Can be applied.

Therefore, according to the present invention, an electric field storage capacitor, a phosphorescent film,
Furthermore, since the passivation film can be formed all at once, a low-cost photosensor array with a high yield can be manufactured.

[Brief explanation of the drawing]

Figure 1 (at is a schematic partial plan view showing a conventional photosensor array, Figure 1 (bl), Figure 1 (c) is XX', YY' in Figure 1 (a) in order of valleys. 2(a) to 2(c) are explanatory diagrams showing embodiments of the present invention, and FIG. 2(b) and FIG.
1 is a schematic cross-sectional view cut at xx'. YY' of FIG. 1 (al). FIG. 6(d) to 6(d) are views showing other embodiments of the present invention, and FIG. 4(a) and FIG. 5(a). Figure 4 (
h) 1 Fig. 4 (cl is a schematic cross-sectional partial view cut in order at XX' and YY' of Fig. 4 (al). Fig. 5 (b) to Fig. 5 (dl, Fig. 6) (b) to 6th
Figures (dl are xx in Figure 5 (a) and Figure 6 (at) in order, respectively.
1-1. It is a schematic cross-section partial view when cut at ', yy; zz'. 1-1. 2-1. 4-1. 5-1. 6-1...
Substrates 1-2, 2-2. 4-2. 5-2. 6-2...
...Semiconductor layer 1-3. 2-3. 4-3. 5-3.6-3...
・Ohmic contact layer 1-4-8% 2-4-a, 4-4-a, 5-4
-a, 6-4-a... Common electrode of photosensor 1-4-b, 2-4-b, 4-4-b, 5
-4-b, 6-4-b...Individual electrode 1-5%
2-5.4-5. 5-5.6-5...Insulating layer 1-6.2-6.4-6. 5-6.6-6...Leaving the common electrode of a capacitor 8he (Japanese) i 4th work b) 84 solid (C)

Claims (1)

[Scope of Claims] In a photosensor array in which a plurality of sensor elements 1 and 7 are arranged in parallel in a row and a charge storage capacitor is provided on the same base, the individual electrodes of the photosensor elements and the capacitor are connected to each other. One t-pole is used as a common electrode, and at least one of the electrodes of the photosensor array or the light! A photosensor array characterized in that a light-shielding member is provided in the light-guiding X layer other than the conversion section. 2. The photosensor array according to claim 1, characterized in that a film of a charge storage capacitor is not used in the passivation film of the nine electric transformer portion. .