JPS63109492A - Matrix display device - Google Patents

Abstract

(57) [Abstract] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed Description of the Invention] Industrial Application Field The present invention is a matrix consisting of a low-cost non-linear two-terminal element with a simple configuration and having high display quality such as high contrast, which is effective for use in video equipment, information equipment, etc. This invention relates to display devices.

BACKGROUND ART In recent years, matrix display devices, particularly liquid crystal display devices, have been actively approached in the field of information equipment centered on computers and in the field of video equipment, in the same way as large-capacity display, especially image display. It is attracting attention as a display that can be used to create low-cost devices. A nonlinear two-terminal element is a two-terminal element that exhibits nonlinear current-voltage characteristics and approximately constant voltage characteristics in a relatively large voltage region. An example of a conventionally proposed liquid crystal display device using a non-linear two-terminal element will be described below with reference to the drawings.

Figure 2(a) shows a nonlinear two-terminal element (MIM element: Met
FIG. 2 is an example of a cross-sectional view of the vicinity of a picture element of one side of the substrate of a liquid crystal display panel in which each picture element is provided with an al-1 nsulator-metal element (Al-1 nsulator-Metal element).

substrate 41, tantalum layer 42, anodized tantalum layer 43,
A non-linear two-terminal element 46 is composed of a picture element electrode layer 44 and a chromium layer 45, and a bus bar 47 and a lead terminal 48
, the pixel electrode layer 49 forms a nonlinear two-terminal array.

[I Triple E, transaction.

On, Electron, Devices, E.D.28I-6-1981 (IEEE TRANSACTIO
N ON ELECTO-RON DEVICES
, VOL, HD-28, N16.1981))Society For In
1984 International Symposium Technical Proceedings (SID International
ional Sympojium Digest Of
Tech-nical Papers) P2O3-
305) Also, Fig. 3 shows an example of PIN diodes connected in a ring shape to form a non-linear two-terminal element.
FIG. 2 is a layout diagram of one side of a substrate of a liquid crystal display panel using an IN diode. In FIG. 3(b) the PIN diode is shown with the usual PN diode symbol. Board 51
On top are a first electrode layer 52, an N-type amorphous silicon 53, an L-type amorphous silicon 54, an N-type amorphous silicon 55, a chromium layer 56, a protective layer 57 made of an insulator, and a second electrode layer 58. is formed, and the PIN diode 59 connected in a ring shape, the bus
The bar 60 and the picture element electrode 61 form a nonlinear two-terminal array. [Television Society Technical Report, May 2, 1982
Announced on the 5th] Normal LCD panels have a duty ratio of 1.
Although the limit is about /200, by using these nonlinear resistance elements, it is possible to obtain high-quality liquid crystal display characteristics with a duty ratio of 1/1000.

FIG. 4 is an equivalent circuit diagram of a liquid crystal display panel using nonlinear two-terminal elements. In order for this panel to work properly,
The current needs to flow mainly through the path of the nonlinear resistor 70 and the capacitor 73 of the liquid crystal layer. In order for the non-linear two-terminal element to function properly, the non-linear resistance parallel capacitance 71 must be made small. Note that 72 is the resistance of the liquid crystal layer, 74 is a non-linear resistance element, and 75 is the liquid crystal layer.

FIG. 5 is a diagram showing the structure of a matrix display panel using nonlinear two-terminal elements. An alignment film 83 is formed on the surfaces of the substrate 80 having strip-shaped electrodes and the non-linear two-terminal element array substrate 81 that are in contact with the display medium 82, glass fibers or fine resin particles are scattered, spacers 84 are provided, and then a sealing material 85 is formed. The display medium 82 is filled in the gap formed by the spacer 84 to form a matrix display device.

Problems to be Solved by the Invention In order to drive, for example, a liquid crystal display device using a non-linear two-terminal element, it is necessary to apply a sufficient voltage to the non-linear element. To achieve this, the capacitance of the non-linear element must be designed to be about 1/10 or less of the capacitance of the liquid crystal layer. Regarding the first method based on the conventional technology, when the thickness of tantalum oxide is about 500 mm, the dark voltage is 7 to IIV and the nonlinear characteristics are also extremely suitable. The capacitance of the linear element increases. Therefore, it is somewhat disadvantageous to obtain high-quality liquid crystal display characteristics with a duty of 1) 500 to 1/1000, and for this reason, the shape of the nonlinear elements is made finer, but this causes a significant deterioration in the yield of arrays. Furthermore, since the photolithography process, which is more complicated and time-consuming, is included at least three times, it not only deteriorates work efficiency but also causes a significant cost increase. Moreover, regarding the second method, the photolithography process is included at least 5 to 6 times, which causes deterioration in work efficiency, deterioration in yield, and further increase in cost.

Means for Solving the Problems In order to solve the above-mentioned problems, the matrix display device of the present invention includes a first conductor layer having gaps in sequence on a substrate, and a plurality of second conductor layers provided for each of the conductor layers. A semiconductor comprising a conductor layer, a resin layer interposed between the first conductor layer and the second conductor layer and electrically connected in cascade, and a compound of arsenic (As), sulfur (S), and selenium (Se). A display medium is sandwiched between a non-linear two-terminal element array having a composite layer of layers and a second substrate having strip-shaped electrodes.

Operation The present invention realizes nonlinear current-voltage characteristics by the semiconductor layer, that is, the nonlinear element portion having the conductor layer-resin layer-semiconductor layer-conductor layer structure with the above-described configuration. It is currently assumed that this nonlinearity is caused to a large extent by the semiconductor layer. Actual element current -
When the voltage characteristics are measured, they show characteristics that can be approximated in the form I=A-Vα. Here, A and α are constants. By interposing this element between the lead wiring and the display electrode, it is possible to increase the ratio between the on voltage and the off voltage applied to the picture element portion, and it is possible to improve contrast characteristics. Furthermore, since the dielectric constant of the compound of arsenic (As), sulfur (S), and selenium (Se) that forms the semiconductor layer is relatively small at 10 or less, the shape of the nonlinear element can be relatively large, which improves the yield. I can hope for it. For example, a first conductor layer patterned on a substrate (usually this is a lead wire) is topped with a semiconductor layer, then a second conductor layer (
Normally, it is possible to stack a part of the picture element electrode (or a connection wiring connecting the semiconductor layer and the picture element electrode) by forming a film twice and performing photolithography twice. However, considering that the nonlinear element has a relatively thick shape and that heating the substrate is not required when the semiconductor layer is formed by vapor deposition, the nonlinear element used in the display device according to the present invention has a relatively large shape. It can be seen that the manufacturing method is simple. That is, the formation of the semiconductor layer on the first conductor layer patterned on the substrate is easily achieved by using a metal mask and performing mask-aligned vapor deposition. Further, the second conductor layer may also be easily formed by subsequent mask vapor deposition depending on what constitutes the second conductor layer.

In addition, the resin layer relieves the stress between the substrate and the semiconductor layer, which contributes to uniformity of characteristics and provides a more stable non-linear two-terminal element. It becomes possible to realize a liquid crystal display device with high display quality at low cost without causing any problems.

Embodiment Hereinafter, a matrix display device according to a typical embodiment of the present invention will be described with reference to the drawings.

As mentioned above, the first conductor layer is the lead wiring or a part thereof branched from the lead wiring, and the second conductor layer is a part of the pixel electrode or a connection for the purpose of connecting to the pixel electrode. It's the wiring. Although it has been confirmed that the effects of the present invention are exhibited in any case, in this example, the following describes the case where the first conductor layer is a lead wiring and the second conductor layer is a part of the pixel electrode. shall be stated.

FIG. 1(a) is a cross-sectional view of the configuration, and FIG. After forming a polyimide film 3 on the entire surface of the board except for the terminals, alignment is performed using a mask made of magnetic stainless steel plate with a thickness of about 30 μm with predetermined holes and an aligner, and samarium film is applied from the back side of the board. Place a cobalt magnet and bring it close together.
Thereafter, this is placed in a vacuum chamber for vapor deposition, and a semiconductor layer 4 is formed on the substrate by a resistance heating method, and a second conductor layer 5 is further formed by a similar method. The substrate l is made of quartz glass, soda glass, etc., and the first conductor N2 is made of indium oxide (IT) containing tin.
O), tin oxide containing antimony, chromium, aluminum, titanium, etc. The semiconductor layer 4 is formed of an alloy of arsenic, sulfur, and selenium, respectively. Further, the second conductor layer 5 is made of tellurium, chromium, aluminum, or the like.

After measuring the current-voltage characteristics of the non-linear two-terminal element array obtained as described above, and performing alignment treatment on the surfaces of the non-linear two-terminal element array and the transparent substrate with strip-shaped electrodes, respectively. The two substrates were bonded together to form a panel, and a display medium was injected to form a liquid crystal display panel.

In one embodiment of the present invention, the substrate 1 shown in FIG. 1 is made of soda glass coated with silicon dioxide (SiO□), and the first conductor layer 2 is made of ITOl or Two types of titanium (Ti) were formed. For each of them, the semiconductor layer 4 is a compound of arsenic, sulfur, and selenium, with sulfur and selenium in the same component ratio, arsenic of 1 atomic %, 5 atomic %, and 1 atomic %.
0 atomic%, 25 atomic%, 40 atomic%, 50 atomic%, 60
A total of nine types of atomic %, 80 atomic %, and 85 atomic % were deposited, and the second conductor layer 5 was a tellurium film with a thickness of approximately 500 ml. The nonlinearity of the current-voltage characteristics of the nonlinear two-terminal element was significantly large, and its capacitance was also sufficiently small compared to the capacitance of the liquid crystal layer. When a liquid crystal display panel was manufactured using these substrates, a display with a contrast of 10:1 or more was confirmed during matrix driving with a duty ratio of 1/1000 and a bias ratio of 1/7.

By the way, in the panel manufacturing process, formation of an alignment film,
When injecting the liquid crystal material, it is necessary to heat the substrate to at least 90°C, but if the arsenic, sulfur, and selenium compound constituting the semiconductor layer 4 has an arsenic content of 10 at%, The device was destroyed during heat treatment due to the significantly lower vitrification temperature. Further, in a device with an arsenic component ratio of 85 atomic %, arsenic precipitation was observed, making it impractical. From the above, it was confirmed that a compound of arsenic, sulfur, and selenium with arsenic content of 10 atomic % or more and 80 atomic % or less has satisfactory characteristics as a nonlinear two-terminal element for liquid crystal display.

In another embodiment of the present invention, the substrate 1 shown in FIG. 1 is made by coating silicon dioxide (SiOz) on soda glass, and the first conductor layer 2 is made by coating silicon dioxide (SiOz) with a thickness of about 1,500 mm. IT
Two types were formed: Ol and titanium (Ti). For each of them, the second conductor layer 5 is coated with a tellurium film with a film thickness of 200 people,
300 people, 500 people, 1000 people, 2000 people, 300
A total of nine types were deposited with 0, 4,000, 5,000, and 8,000 people. The semiconductor layer 4 contains 2 sulfur
Approximately 100 people deposited selenium arsenic (AsSeS). The nonlinearity of the current-voltage characteristics of the nonlinear two-terminal device obtained as described above was extremely large, and the capacitance thereof was also sufficiently small compared to the capacitance of the liquid crystal layer.

When a liquid crystal display panel was manufactured using these substrates, a display with a contrast of 10:1 or more was confirmed during matrix driving with a duty ratio of 1/1000 and a bias ratio of 1/7.

In another embodiment of the present invention, the substrate 1 shown in FIG. 1 is made of soda glass coated with silicon dioxide (SiO□), and the first conductor layer 2 is made of ITO with a thickness of approximately 2,500 mm. Alternatively, two types of titanium (Ti) were formed. For each of them, the second conductor layer 5 is made of chromium (Cr) and aluminum (
A1) A total of six types of films with film thicknesses of 500, 1,000, and 2,000 were deposited, and the semiconductor layer 4 was made of 1
Approximately 1,500 people deposited sulfur, selenium, and arsenic (AsSezS). The nonlinearity of the current-voltage characteristics of the nonlinear two-terminal device obtained as described above was extremely large, and the capacitance thereof was also sufficiently small compared to the capacitance of the liquid crystal layer.

When a liquid crystal display panel was manufactured using these substrates, a display with a contrast of 10:1 or more was confirmed during matrix driving with a duty ratio of 1/1000 and a bias ratio of 1/7.

In another embodiment of the present invention, the substrate 1 shown in FIG. 1 is made of soda glass coated with silicon dioxide (SiOz), and the first conductor layer 2 is made of chromium (SiOz) with a thickness of about 1,500 mm. C
r), aluminum (Al), or antimony (Sb
) is formed, and after forming a polyimide film, a semiconductor layer 4 (2 sulfur, 1 selenide, 2 arsenic (A S
2 S e Sz )) was deposited by 2,000 people, and the second conductor layer 5 (tellurium) was deposited by 500 people in turn by a resistance heating method. The nonlinearity of the current-voltage characteristics of the nonlinear two-terminal device obtained as described above was extremely large, and the capacitance thereof was also sufficiently small compared to the capacitance of the liquid crystal layer. When a liquid crystal display panel was manufactured using these substrates, a display with a contrast of 10:1 or more was confirmed during matrix driving with a duty ratio of 1/1000 and a bias ratio of 1/7.

In another embodiment of the present invention, the substrate 1 shown in FIG. 1 is made of soda glass coated with silicon dioxide (Sing), and the first conductor layer 2 is made of ITO with a thickness of about 2000. or titanium (Ti), and the semiconductor layer 4 for each of them is made of 1 sulfur 2 selenium 2 arsenic (AszSag).
S) with film thickness of 300, 500, 1000, 2
000 people, 3000 people, 4000 people, 5000 people, 60
A total of eight types were deposited, each with a total of 00 people. A 400-layer tellurium coating was formed on the second conductor layer 5. The nonlinearity of the current-voltage characteristics of the nonlinear two-terminal device obtained as described above was extremely large, and the capacitance thereof was also sufficiently small compared to the capacitance of the liquid crystal layer. When a liquid crystal display panel was manufactured using these substrates, display with a contrast of 1O:1 or more was confirmed during matrix driving with a duty ratio of 1/1000 and a bias ratio of 1/7.

In another embodiment of the invention, the group Fi1 shown in FIG.
Soda glass is coated with silicon dioxide (SiO□), and the first conductor layer 2 is made of ITO with a thickness of approximately 2000 mm.
or titanium (Ti), and for each of them, the semiconductor N4 is a compound of arsenic, sulfur, and selenium, with the component ratio of arsenic being 30 at% and 50 at%, and the remaining component ratio being sulfur: selenium. =s:t, 3:1, 1:1, 1:3
, a total of 10 types with a ratio of 1:5, about 2000 each.
Deposited.

The second conductor layer 5 formed a 200-layer tellurium coating.

The nonlinearity of the current-voltage characteristics of the nonlinear two-terminal device obtained as described above was extremely large, and the capacitance thereof was also sufficiently small compared to the capacitance of the liquid crystal layer. When a liquid crystal display panel was manufactured using these substrates, a display with a contrast of 10:1 or more was confirmed during matrix driving with a duty ratio of 1/1000 and a bias ratio of 1/7.

In the embodiments of the present invention, a method using a metal mask was used to batten the semiconductor layer and the second conductor layer, but even if a lift-off method using a photoresist was used,
Further, as a display medium, for example, an electrophoretic display device (EPID) other than a liquid crystal composition.

It goes without saying that similar results can be obtained when an electroluminescent display element (EL), an electrochromic display element (ECD), or the like is used.

Effects of the Invention As described above, the matrix display device of the present invention includes a first conductor layer having gaps on a substrate, a resin layer, and a semiconductor made of a compound of arsenic (As), sulfur (S), and selenium (Se). By having a structure in which a conductor layer and a second conductor layer are laminated, defects such as peeling do not occur in a simple process that does not use a photolithography process or a lift-off process as shown in the example. A nonlinear two-terminal array for matrix display that exhibits stable characteristics was obtained, and not only work efficiency and yield were significantly improved, but also a matrix display device with high display quality could be realized at low cost.

[Brief explanation of the drawing]

FIG. 1(a) is a cross-sectional view of the configuration of a non-linear two-terminal element for liquid crystal display according to the present invention, FIG. 1(b) is a plan view thereof, and FIG.
a) and FIG. 3(a) are cross-sectional views of the configuration of a conventional non-linear two-terminal element, FIG. 2 (bl) and FIG. An equivalent circuit diagram of a liquid crystal display panel with linear two-terminal elements, and FIG. 5 is a configuration diagram of a matrix display panel using non-linear two-terminal elements. 1...Substrate, 2... first conductor layer, 3.
...Polyimide layer, 4...Semiconductor layer, 5
...Second conductor layer. Name of agent: Patent attorney Toshio Nakao (1 person) /-Basic sales?-1st conductor 1 Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 "J8/

Claims (6)

[Claims] (1) A first conductor layer having gaps sequentially on the substrate, a plurality of second conductor layers provided for each of the conductor layers, interposed between the first conductor layer and the second conductor layer, a composite layer of a resin layer and a semiconductor layer made of a compound of arsenic (As), sulfur (S), and selenium (Se) which are cascade-connected; the resin layer is in contact with the substrate; A matrix display device characterized in that a display medium is sandwiched between a non-linear two-terminal element array and a second substrate having strip-shaped electrodes. (2) The matrix display according to claim (1), characterized in that, in the compound of arsenic, sulfur, and selenium constituting the semiconductor layer, the component ratio of arsenic is 10 atomic % or more and 80 atomic % or less Device. (3) The first conductor layer is indium oxide (In_2O_3) containing tin (Sn), tin oxide (SnO_2) containing antimony (Sb), chromium (Cr), aluminum (A
1) The matrix display device according to claim 1, wherein the matrix display device is made of either titanium (Ti). (4) The second conductor layer is indium oxide (In_2O_3) containing tin (Sn), tellurium (Te), aluminum (
Claims (1) and (1) are made of any one of Al), chromium (Cr), and titanium (Ti).
The matrix display device according to either item 2) or item (3). (5) The matrix display according to any one of claims (1), (2), (3), or (4), wherein the resin layer is formed of polyimide. Device. (6) Claim (1), characterized in that the display medium is made of any one of a liquid crystal composition, an electrophoretic display element, an electroluminescent display element, and an electrochromic display element;
The matrix display device according to any one of item (2), item (3), item (4), or item (5).