JPH05249498A - Electronic device and operating method therefor and production thereof - Google Patents

Abstract

PURPOSE:To prevent a degradation in yield by forming a semiconductor integrated circuit equiv. to an IC chip on the substrate of a display element or input device in order to eliminate high-density packaging of IC chips. CONSTITUTION:The display element for which, for example, solar batteries are used, has a solar battery element region 102, the integrated circuit region 103 and further a display element electrode region 104 of a segment type on a glass substrate 101. The production of the respective regions is separately executed. The semiconductor integrated circuit region 103 is formed by connecting TFTs with aluminum wirings. The pixel electrodes of the liquid crystal display region 104 is formed via a chromium film. The semiconductor integrated circuit 103 and the respective pixel electrodes of the display element region 104 are electrically connected to form the solar battery region 102 consisting of PIN 3 layers of amorphous silicon. A rear surface substrate is superposed thereon and a TN liquid crystal is injected therebetween. A polarizing plate is superposed thereon, by which the display device is constituted. This device is packaged by positioning the rear surface of the surface A of the substrate 101 on which the element is not formed to a front side.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a device requiring a large number of output terminals such as a segment type or matrix type display device, a device having a large number of input switches, and a method for manufacturing the same. The present invention relates to a semiconductor integrated circuit attached to the above device, which is incorporated on the same substrate as the device. In particular, the present invention aims to provide a device that can provide a large amount of display information at low cost.

[0002]

2. Description of the Related Art Display devices used in calculators and other devices are roughly classified into a segment system and a matrix system. In any of the methods currently used, one electrode of a display element is selectively formed by a transparent conductive material film such as ITO on an insulating substrate such as glass, and a large number of electrodes extending from the electrode are formed. The wiring is connected to a single crystal semiconductor integrated circuit (IC) chip.

As the connection method, wire bonding method, TAB (tape automatic bonding) method, COG
The (chip on glass) method is known. Of these, the COG method is the most highly integrated method. An example thereof is shown in FIG.

In the COG method, the IC chip 202 is directly
Alternatively, the anisotropic conductive material is sandwiched between the display element substrate 201 and
Glue to. At this time, the adhesive portion 203 of the display element substrate
Is provided with an electrode for connection. Figure 2
As shown in the enlarged view of (A), as can be seen, a large number of terminals 204 must be formed. Moreover, since the IC chip must be exactly connected to these terminals, the IC chip alignment is required to be accurate. Normally, in the COG method, the distance between adjacent terminals is 10
Since it is about 0 μm, the same accuracy is required for the alignment of the IC chip.

On the other hand, the number of terminals depends on the display capacity of the display element. For example, in the 7-segment display, 8 lines including the decimal point extend for each character (digit).
Eight terminals must be formed. For example, 10
When displaying characters (digits), 80 terminals are formed,
All of these terminals must be connected to the corresponding terminals of the IC chip. Therefore, the yield in this COG process was not high.

Further, as is clear from the figure, the wirings are crowded near the connecting portion, and a short circuit may occur between the adjacent wirings, or the wirings may be broken. In particular, the probability of occurrence of such a defect increases remarkably when the wiring interval becomes narrow and the wiring width becomes small.

A block diagram of a commercially available calculator is shown in FIG. This is a calculator using a solar cell, but as shown in the figure, an input device consisting of push buttons, an arithmetic circuit,
It is composed of a segment type liquid crystal display device, a control circuit for driving the liquid crystal display device, a solar cell and a backup power supply (battery).

In a calculator having a simple type of calculation, the calculation circuit and the control circuit of a liquid crystal display (LCD) are often integrated into one IC chip. In a device capable of high-level arithmetic, it is divided into a plurality of arithmetic chips and an LCD control chip. In both the matrix system and the segment system, the display element itself cannot display the numerical value (digital signal) emitted from the arithmetic circuit as a numerical value. Therefore, a control circuit for decoding the digital signal and sending the signal to each electrode of the LCD is required. And when connecting such a control circuit and a display element,
The above problems have arisen.

An input device such as a keyboard has the same problem. In an input device with multiple switches, the signals from each switch are collected into a digital signal,
It was necessary to flow it out by one output signal line. An IC chip is required for such signal processing,
The work of connecting a large number of wires extending from each switch (key) and the IC chip was very time-consuming, and the yield was not high.

[0010]

SUMMARY OF THE INVENTION The present invention has been made in order to solve the problems of the conventional display device or input device, and in particular, the COG method and other IC chips that directly lead to a decrease in yield. The present invention relates to display devices and input devices that do not require mounting technology, and their applied products.

[0011]

The present invention is intended to form a semiconductor integrated circuit having a function equivalent to that of an IC chip on a display element or an input device substrate in order to eliminate high-density IC chip mounting. For example, in the present invention, not only the transparent electrodes of the display element but also the control circuit of the display element and, in some cases, other arithmetic / logic circuits are integrated on the transparent insulating substrate used for the display element. Suggest things. In this way, since the display element and the integrated circuit are formed on the same substrate, the chip mounting process becomes unnecessary, and the yield resulting from it is not reduced.

Of course, in forming an integrated circuit, an unsuitable substrate material cannot be used. For example, when a polycrystalline silicon TFT manufactured by a high temperature process (maximum process temperature of 1000 ° C. or higher) is used as an integrated circuit, quartz is preferable as the substrate. Further, in a polycrystalline silicon TFT manufactured by a low temperature process (maximum process temperature of 550 ° C. or higher), various non-alkali glasses can be used in addition to the quartz substrate. The choice of substrate depends on the fabrication process.

When the present invention is applied to a display element, other elements may be formed on such a substrate in addition to the transparent electrode of the display element and the integrated circuit. For example, when applied to a calculator, a photoelectric conversion element such as a solar cell may be formed on the same substrate as a power source. An example is shown in FIG. As shown in FIG. 1A, the electronic device of the present invention has an integrated circuit region 1 including a solar cell element region 102, a logic / arithmetic circuit, and a display element control circuit on a glass substrate 101.
03, and a segment type display element electrode region 104. A matrix method may be adopted instead of the segment method. Since a thin film forming technique may be applied to the connection of these regions, defects such as connection defects, disconnections, and short circuits do not occur unlike the case of using the COG method or other methods. Therefore, it exerts a sufficient effect in improving the yield. In particular, a display element driving circuit of such an integrated circuit is provided with a display element (9-digit segment system).
If it is formed in a slender shape in accordance with the above, the density of the wiring is reduced, and it is extremely effective for defects such as disconnection and short circuit.

[0014]

【Example】

[Embodiment 1] FIG. 1B shows a plastic package 1 having a push button 105 for the electronic device of the present invention.
An example of a calculator incorporated in 06 is shown below. As shown in FIG. 1 (A), the electronic device of the present invention has an integrated circuit region 103 made of an aluminum gate silicon TFT manufactured by a low temperature process and an ITO for a liquid crystal display element on a 7059 glass substrate 101 manufactured by Corning. The segment type transparent conductive film region (display element region) 104 and the PIN type amorphous silicon solar cell region 102 are formed. A publicly known method may be applied to each element technology. For example, Japanese Patent Application No. 3-237, which is an invention of the present inventors, regarding the production of a low temperature silicon TFT.
100, the same 3-238713, the same 4-30220, etc. may be referred to.

Each area was manufactured separately. First, a TFT was manufactured by a low temperature process. The maximum process temperature at this time was 600 ° C. After that, each TFT was connected by an aluminum wiring to form a semiconductor integrated circuit region 103, and then a pixel electrode of a liquid crystal display region 104 was formed of ITO via a chromium film. At this time, the semiconductor integrated circuit 103 and each pixel electrode in the display element region 104 were electrically connected. Further, the solar cell region 102 formed of a PIN3 layer of amorphous silicon was formed by the plasma CVD method. Since the maximum process temperature for producing the solar cell region affects the aluminum wiring of the semiconductor integrated circuit portion, it is desirable that the temperature is as low as possible. In this example, the maximum process temperature was 250 to 350 ° C. At the final stage of forming the solar cell region 102, an aluminum film is formed as a back surface electrode, and in this step, connection to the semiconductor integrated circuit portion is also performed. After that, a liquid crystal alignment film was formed to complete the electronic device.

A back substrate is stacked on the electronic device of FIG. 1A thus manufactured, TN liquid crystal is injected, and a polarizing plate is further stacked to complete a display device. Unformed surface (ie, FIG. 1)
The back side of (A) was used as the front side for packaging. The substantial limit of the thickness of this package excluding the push button is determined by the thickness of the back substrate facing the glass substrate 101, and is typically up to about 1 mm. Although it was possible to make it less than that, there was a problem due to mechanical strength. In this embodiment, as shown in FIG. 1, the semiconductor integrated circuit region 103 has an elongated shape, and
Solar cell area 102 and liquid crystal segment display element area 10
It has a structure sandwiched between 4. Such an arrangement has advantages such as shortening the wiring, reducing noise and preventing disconnection when sending a signal to the display element while supplying power to the semiconductor integrated circuit area, and is extremely efficient. Met. Also,
In this semiconductor integrated circuit area, necessary arithmetic circuits and circuits for driving display elements are incorporated. As described above, by arranging the semiconductor integrated circuit region adjacent to the display element region, it is possible to easily connect the wiring to the display element, and reduce defects such as disconnection and short circuit due to congestion of the wiring. In particular, in order to effectively send a signal to the display element and simplify the wiring, it is desired that the length of the semiconductor integrated circuit area be substantially the same as the length of the display element area as in this embodiment.

[Embodiment 2] In this embodiment, an electronic device in which a semiconductor integrated circuit, a matrix type liquid crystal display panel, a solar cell and an optical input switch device are incorporated on one substrate will be described. As shown in FIG. 3 (A), the device manufactured in this example is made of transparent glass (Corning 70
59) Solar cell 303, arithmetic circuit 30 on substrate 302
7, a matrix type (320 × 128 dot) TN liquid crystal display panel 308, a scan driver circuit 305, data driver circuits 304 and 306, and an optical input device 309 are formed integrally. The surface on which these elements and devices are formed is made to face the glass back substrate 310, and the liquid crystal injected between them is covered with a resin package 301 for mechanical protection. Although not shown in the figure, a polarizing plate is also provided.

Explaining the liquid crystal display panel, the screen is of a passive matrix type in which the screen is vertically divided into two and driven at a 1/64 duty. Conventionally, such a matrix type display panel has been adopted only in high-end models, but it is necessary to connect the IC chips by the TAB method or the COG method in order to drive the matrix. This is because it took a lot of time. In addition, the entire device was large and heavy due to these connections.

However, the simple segment method has a limit in display capacity, which limits the purpose of use. For example, displaying numbers was fine, but displaying alphabets and kana characters required complex segments, making it almost impossible to display kanji. On the other hand, there was a strong need for displaying kanji and alphabets. The present invention can be said to be suitable for such needs. The cost is less than half that of the COG method. However, in order to obtain a clear display with 1/64 duty driving, even if the threshold voltage of the liquid crystal is about 3V,
The applied voltage needs to be 10 V or higher, preferably 15 to 30 V. Therefore, in the present invention, a booster circuit is provided and a TFT having a high breakdown voltage and anodized aluminum gate is used. Regarding the manufacturing method and structure of this TFT, for example, Japanese Patent Application No. 3-2 which is the invention of the present inventors.
37100, 3-238713, 4-302220, etc. may be referred to.

In this electronic device, input is performed optically without using a push button type input switch such as those used in ordinary computers and calculators. That is, each input switch 309 of this embodiment has a small optical sensor portion 311 formed in the center thereof. This optical sensor may be made of a material such as a compound semiconductor such as CdSe or CdTe whose conductivity changes by irradiation with light as it is, but it is a material sensitive to light such as amorphous silicon. You may use what formed the laminated structure. The latter is used in this embodiment because it can be formed at the same time when the solar cell 303 is formed. In the present embodiment, the display portion 309 of the input switch (actually, only the portion corresponding to the button is printed, and the structure is not particularly different from other substrate portions) 309 is set to 6 mm × 6 mm. On the other hand, the photosensor portion 311 was made extremely small as 0.5 mm × 0.5 mm and formed at the center of each display portion.

The principle of operation of such an optical input device will be described. The circuit diagram is shown in FIG. That is, the respective photosensors (comprising a photodiode and a charge storage capacitor) 311 are connected in parallel by common wiring. When an input is to be made in this device, the display of the switch portion is pressed with a finger, but the light to the optical sensor in the pressed portion is blocked. The input is done by that. The signals from these photosensors are collected in the signal comparison circuit 312. In this signal comparison circuit, the signals from each photosensor are periodically compared. In this embodiment, 0.2
The signal of the optical sensor is sampled every second,
The data was integrated. That is, in order to input a signal, it is necessary to hold the switch portion with a finger for about 0.2 seconds. However, the input may be discriminated even if the time is shorter than that (for example, about 0.1 second). Also,
It is necessary to take preventive measures so that data will not be overlapped when input is continued for 0.2 seconds or longer. For example, if you press and hold the same switch for about 1 second,
Since the sampling is performed about times, there is a risk that it is determined that the same input signal is input five times in succession. However, it is easy to solve such a problem, and a program that invalidates the result of the second sampling if the same input as the first sampling result is continuously made during the second sampling. Build a flow chart. To further strengthen this, a program flow chart in which all input signals are invalid unless there is no input for at least one sampling period after the first input is made. Good.

In the present embodiment, the average value and standard deviation of the signals collected from the respective optical sensors are obtained, and the minimum value and the optical sensor which has transmitted the minimum value are determined. In principle,
The switch part of the optical sensor that sends the minimum value is considered as the input. However, the light that hits such an optical sensor varies depending on the place, so even if you do not press the button, the part where the light incident happens to emit the lowest value due to the reason such as the shadow of your finger. Sometimes, erroneous input occurs. In order to avoid this, in this embodiment, a mechanism is adopted in which the standard deviation is calculated and only the switch portion that has transmitted the intentional data is determined as the input. That is, in the present embodiment, when the lowest value was obtained, only when the value was (average value-standard deviation) or less was determined as an input. Therefore, we tried to prevent accidental input by accidental factors.

To further enhance this method, for example,
A method may be adopted in which only one signal having (average value-standard deviation) or less is used as an input signal, and when there are two or more signals, no input is considered.

Although the method of using the standard deviation is effective in discriminating between the intentional one and the accidental one, for example, when the operation is performed in a sufficiently bright environment, Even an accidental signal such as the shadow of
Standard deviation). In that case, the latter method of the former two methods cannot be used. Also, in the former method, even if the shadow of the finger happens to pass through the switch part, the signal emitted by the optical sensor is
It is sufficiently smaller than other signals, and falls below a reference value such as (average value-standard deviation), resulting in erroneous input.

In order to avoid such a problem, the signals emitted from the respective photosensors are passed through a limiter, all signals above a certain level are regarded as the same value, and then the average value and standard deviation are calculated, The above determination may be performed.
Alternatively, the signal having a certain output level or more may be excluded from the beginning, and the average value and the standard deviation may be calculated only for the signals having the certain output level or less to make the determination.

In the present embodiment, the above mathematical formula is adopted as a standard for distinguishing between the intentional input signal and the accidental input signal, but it goes without saying that another standard mathematical formula may be adopted. .. Alternatively, two lower signal levels may be determined, and the determination may be made based on whether or not the difference is a certain value or more.

After the input signal is discriminated in this way, a signal is transmitted from the signal comparison circuit 312 and input to the circuit 313 at the input stage of the arithmetic circuit. In this example,
Since the input operation is not mechanical as in the past, the structure is extremely simple, and there is no reduction in reliability due to mechanical damage (for example, push button destruction). In particular, since the switch portion and the arithmetic circuit can be formed on one substrate, there is substantially no wiring connecting step, the yield is improved, and the cost can be reduced.

In the conventional pocket computer of this type, the production of the keyboard portion composed of push buttons was a labor-intensive operation of soldering the wiring of each button. Further, the button portion needs to have mechanically sufficient reliability and needs a high-grade material. In addition, the button part was the first to break when continued use. Therefore, the cost of the keyboard or push button has become extremely high.

In reality, when such labor-intensive work is performed in Japan, where labor is insufficient, the cost is extremely high, so that it is almost always produced in countries with low labor costs such as Taiwan and Malaysia. It was However, in recent years, as labor costs have risen in these countries as well, there are moves to move manufacturing bases to Bangladesh and India, where wages are even lower. For Japan, this is a problem of hollowing out of industry. Of course, it is preferable in terms of distributing wealth to developing countries, but in reality, the method of transporting parts from Japan to these overseas bases, assembling them overseas, and then shipping them back to Japan is adopted. ing. Therefore, the cost of transporting products and parts is enormous. The cost increases as the manufacturing base becomes farther from Japan. We must not forget the fact that transportation is not only expensive but also consumes a lot of oil. Considering environmental problems such as global warming, it is obvious that it is desirable to consistently produce without unnecessary transport.

The manufacture of the device shown in this example is not labor intensive. Therefore, even if it is produced in Japan, the cost is low, and rather Japan with better infrastructure is more suitable for production. The degree of environmental damage caused by transportation will be significantly reduced.

[Embodiment 3] FIG. 4 shows an example of steps for carrying out the present invention. First, a silicon nitride film for blocking mobile ions such as alkali ions is formed over the glass substrate 401. It is desirable that the substrate material contains no or low alkali content. The most preferable substrate is a quartz substrate, and in particular, synthetic quartz has no alkali ions contained in the substrate. Since quartz has excellent heat resistance, a gate oxide film can be formed by a thermal oxidation method when forming a semiconductor integrated circuit. When such an ideal substrate material is used, the silicon nitride film 402 need not be provided. However, large quartz substrates are very expensive. That is, the substrate cost per unit area increases as the area increases. Therefore, when a large-sized device is formed, the cost of the substrate becomes ridiculous if the quartz substrate is used. As a substitute material, various alkali-free glasses can be used. For example, Corning 705
9 glass, 1733 glass, 1724 glass, 1729
Examples thereof include glass, N-0 glass manufactured by Nippon Electric Glass Co., Ltd., and NH-35 glass manufactured by NH Techno Glass Co., Ltd. These substrates are
When a liquid crystal display is adopted as the display method, it is desirable to use a polished one without waviness or warpage in order to keep the cell thickness constant. Further, since each glass has a different strain point, it is necessary to select a glass suitable for the maximum temperature of the manufacturing process. Below, the example which uses a non-quartz glass substrate is shown.

The method of forming the silicon nitride film is carried out by a known low pressure CV method.
The D method or the plasma CVD method may be used. Silicon nitride film 4
A silicon oxide film 403 was deposited on 02. The thickness varies depending on the quality of the silicon nitride film, but is 30 to 1000 n.
m is preferred. As a film forming method, a sputtering method or ECR
The plasma CVD method was suitable.

Further, the ITO film 4 is formed by the sputtering method.
04 was selectively formed. This ITO film becomes an electrode on the incident side of the solar cell region. A suitable thickness is 20 to 500 nm. If it is too thin, the sheet resistance increases, which is not preferable. Then, an N-type silicon carbide film 405 was selectively formed by a plasma CVD method or a low pressure CVD method. The thickness is preferably 30 to 200 nm. Further, a substantially intrinsic silicon film is formed thereon and patterned to form an I layer 406 in the solar cell region and a T layer in the integrated circuit region.
An FT active layer 407 was formed. The thickness is 2
0-200 nm is preferable. In this example,
Since the silicon films 406 and 407 are formed at the same time, they have the same thickness. Therefore, the silicon films 406 and 407 must be made to have a thickness suitable for use in both a solar cell and a TFT. Silicon film 406 in the solar cell area
With respect to the above, it is convenient to employ a structure in which the N-type silicon film 405 is completely covered, because a short circuit in a later step can be prevented.

In this state, the silicon substrate was crystallized by thermal annealing of the substrate. When the raw material for the silicon film is silane, the annealing temperature is 55.
0-650 ° C was preferred. When the material of the silicon film is disilane instead of silane, the annealing temperature is further increased to 5
It was possible to lower the temperature by 0 ° C. The annealing atmosphere is preferably nitrogen, hydrogen, or vacuum. The annealing time was 12 to 72 hours depending on the temperature.

After that, the sputtering method and the ECR plasma CV are used.
A gate oxide film 408 was formed by the D method. Thickness is 100 ~
300 nm was preferred. In this way, FIG.
(A) was obtained.

After that, the gate electrode of the TFT was formed of aluminum. A sputtering method or an electron beam evaporation method is desirable for forming the aluminum film. After patterning aluminum, aluminum oxide was formed on the surface and side surfaces of the aluminum film by an anodic oxidation method to form a gate electrode portion. That is, a substantial gate electrode 409 and an aluminum oxide film 410 were formed around it. The anodic oxidation method is described in Japanese Patent Application No. 3-2371, filed by the present inventor.
00, 3-238713, 4-302220, etc. may be referred to.

After that, ion implantation was performed with the photoresist 411 covering the solar cell region to form an N-type impurity region (source, drain) 412. Although only NMOS is described in FIG. 4, when forming a CMOS circuit, it is necessary to similarly perform P-type impurity implantation in the PMOS TFT. Of course, it is desirable that the solar cell region is masked at that time as well.

After this step, the crystal broken by the ion implantation was recrystallized by the laser annealing method. Regarding the conditions of laser annealing, the above application was also referred to. Thus, FIG. 4B was obtained.

After removing the photoresist, a P-type silicon film 413 was selectively formed in the solar cell region by a low pressure CVD method or a plasma CVD method. Thickness is 30 ~ 200nm
Is desirable. In this way, the PIN structure of the solar cell region was completed. As is clear from the above description, the I layer in the solar cell region is substantially in the polycrystalline state like the active layer of the TFT, and exhibits a better energy conversion efficiency than the conventional amorphous silicon.

After that, an interlayer insulator 414 was formed, holes for electrodes were opened, an aluminum film was formed, and aluminum wirings 415 and 416 were formed. At this time, a chromium film may be formed on the aluminum coating to form an aluminum / chrome multilayer structure. By forming the upper surface with chromium in this way, it is possible to reduce the resistance at the boundary when the ITO film is formed later. Then IT
An O film was selectively formed to form an electrode 417 in the display pixel area. This state is shown in FIG.

On the other hand, on the other glass substrate 418, a metal coating 419 of chromium, aluminum or the like was formed only on the display pixel region. This will be a reflector. As the glass substrate 418, a material containing an alkali can be used. Polyimide resin was flatly formed on both substrates thus obtained, and rubbing treatment was performed to obtain alignment films 420 and 421. Then, both substrates were opposed to each other, and a liquid crystal material, for example, TN liquid crystal 422 was injected between them to seal the substrates. In this way, an electronic device having a solar cell region, an integrated circuit region, and a display pixel region was manufactured. The cross section is shown in FIG.

[0042]

The electronic device which is the object of the present invention is most simply a display device or a device having a large number of input switches and its peripheral circuits formed on the same substrate, and an arithmetic circuit, a memory circuit, etc. Further semiconductor integrated circuits, power supply elements such as solar cells, and elements such as input elements such as optical sensors are integrated. as a result,
In the conventional electronic device, it was possible to incorporate functions that could not be realized in terms of cost.

For example, according to the present invention, a matrix type display device which has been difficult and expensive to manufacture can be manufactured at low cost. This is particularly effective for small areas. For example, in the case of a large STN liquid crystal panel with 640 × 480 dots, the number of ICs required for TAB connection is 11 (160 IC terminals, 1/24 IC terminals).
When the unit price of the IC is 1,000 yen in the case of 0 duty driving), the cost is 11,000 yen. On the other hand, if this is a TN liquid crystal panel of 320 × 120 dots of 1/8 scale, the number of required ICs is 5, and the cost is 5,000 yen, which is 1/8 according to the scale of the matrix. It doesn't. That is, the smaller the area, the higher the cost.

On the contrary, if an attempt is made to fabricate a drive circuit having a matrix of 640 × 480 dots according to the present invention, the cost will be extremely high. This is because the cost of the substrate increases and the yield decreases as the circuit scale increases. However, with a matrix that is 1 / 8th the size, the cost drops dramatically. Estimated cost is 1/100
The total cost is about 2,000 yen, which is far less than 6,000 yen in the TAB connection method. For example, in the case of a 320 × 120 dot panel and TAB connection, if the STN liquid crystal is used instead of the TN liquid crystal, the number of ICs used can be reduced to three.
This is because the STN liquid crystal is suitable for high duty driving. In that case, the total cost is 4,000 yen. However, the STN liquid crystal requires a delicate control of the cell thickness and has a coloring effect. To remove it, a retardation film or the like must be used, and the viewing angle is narrow. Overall, the characteristics are not good compared to TN liquid crystal.

Further, in the optical input device (switch substrate or switch panel) as described in the second embodiment, the arithmetic circuit and the substrate are the same, so that a synergistic effect can be obtained. That is, even if it is used alone, it does not require mechanical parts, there is no decrease in reliability due to mechanical destruction, there is little physical fatigue due to use, and benefits such as failure do not occur easily. Even if you can do it, the final cost will not be different from the conventional push button type considering the connection problem. In the present invention, not only a large number of optical sensors are formed on such a switch substrate, but also an integrated circuit for discriminating these inputs is formed at the same time, thereby eliminating the need for wiring connection. For example, if the switch board has only 20 photosensors arranged, the wiring that comes out from it is 20
It is a book and these must be connected to the IC chip of the required signal processing circuit. However, in the present invention,
Since 20 photosensors and the circuit that processes the signals obtained from those sensors are also formed on the same substrate, only one wiring that outputs a digital signal will eventually be output (strictly speaking, the power supply line as well). Since it is necessary (if necessary) to be connected to the outside, the labor for wiring connection is significantly reduced. Furthermore, by incorporating an arithmetic circuit and a display device on the same substrate as in the second embodiment, a system can be constructed without the trouble of wiring. Thus, the present invention is an industrially extremely useful invention.

[Brief description of drawings]

FIG. 1 shows an example (calculator) of an electronic device according to the invention.

FIG. 2 shows a method of connecting a display portion of a conventional electronic device.

FIG. 3 shows an example of an electronic device according to the invention.

FIG. 4 shows an example of a manufacturing process of an electronic device according to the present invention.

[Explanation of symbols]

 101 ・ ・ ・ Substrate 102 ・ ・ ・ Solar cell area 103 ・ ・ ・ Arithmetic circuit area 104 ・ ・ ・ Segment type liquid crystal display area 105 ・ ・ ・ Button 106 ・ ・ ・ Package

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁵ Identification code Office reference number FI technical display location H01L 31/04

Claims (8)

[Claims] 1. A semiconductor integrated circuit composed of a single crystal, a polycrystal, or a substantially polycrystal semiconductor on a single insulating substrate, and a transparent conductive film used as a pixel electrode of a display element. And electronic device. 2. The electronic device according to claim 1, wherein the thin film photoelectric conversion element is provided on the same substrate. 3. The electronic device according to claim 1, wherein a thin film optical sensor is provided on the same substrate as the input device. 4. The electronic device according to claim 2, wherein a portion of the semiconductor thin film forming the photoelectric conversion element, which is closer to the substrate, is made of a single crystal, polycrystal, or substantially polycrystal semiconductor. 5. The electronic device according to claim 2, wherein a part or all of the semiconductor integrated circuit has an elongated shape sandwiched between the photoelectric conversion element region and the display element region. 6. The electronic device according to claim 5, wherein the semiconductor integrated circuit region has substantially the same length as the display element region. 7. A step of selectively forming a P-type or N-type first semiconductor film on the insulating substrate, and a step of selectively forming a substantially I-type second semiconductor film thereafter. ,
The step of forming a gate insulating film on the portion of the second semiconductor film where the first semiconductor film is not formed, the step of forming a gate electrode thereafter, and the step of forming an N-type or P-type third film And a step of forming a semiconductor film. 8. In a device having a plurality of optical sensors, the output signals of all the optical sensors are compared to obtain the minimum value, the average value, and the standard deviation, and the minimum value, the average value, and the standard of the detected light. Input of an electronic device characterized by recognizing the sensor showing the minimum value as the selected sensor when there is only one sensor whose difference from the reference formula expressed using the deviation is equal to or greater than the threshold value. Signal detection method.