JPH08271932A - Liquid crystal display device - Google Patents

Abstract

PURPOSE: To provide an active matrix type liquid crystal display device in which a nonlinear resistance element having a metal-insulating material-metal structure and using a plastic substrate is used as a switching element. CONSTITUTION: A silicon oxide inorg. thin film 2 is formed on a polysulfone substrate 1, and a nonlinear resistance element 6 comprising a tantalum electrode 3, tantalum oxide nonlinear resistance film 4 and titanium electrode 5 is formed on the substrate 1. An oxide layer 7 of tantalum oxide is formed between the nonlinear resistance element 6 and the inorg. thin film 2. An ITO transparent electrode 8 for driving a liquid crystal is formed on the inorg. thin film 2 so that the electrode 8 is partly overlapped on the upper electrode 5. Then an orienting film 9 is formed to constitute a matrix array substrate 10. By forming the inorg. thin film 2 between the lower electrode 3 and the polysulfone substrate 1, the lower electrode 3 can be tightly adhered to the polysulfone substrate 1 and the polysulfone substrate 1 is hardly damaged during etching.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION The present invention relates to a conductor-nonlinear resistance film-
The present invention relates to a liquid crystal display device using a non-linear resistance element provided with a conductor.

[0002]

2. Description of the Related Art In recent years, in addition to displays on clocks, calculators, and various measuring devices, small-sized communication devices, portable information terminal devices, and the like are required to have a light weight, robustness, versatility in design, space restrictions, and plastic substrates. The demand for liquid crystal displays using LCDs is increasing. In order to meet such a demand, a conventional simple matrix liquid crystal display has a resolution of 0.
It is known to use a plastic film having a thickness of about 1 mm as a substrate.

[0003]

However, even though the simple matrix is small, it cannot be applied to the ones that require high performance, number of pixels, response speed and the like.
In other words, the active matrix method is the way to improve the performance, but in the method using the thin film transistor (Thin Film Transistor) for the switching element, the film forming temperature becomes 300 ° C. or more, and it is impossible to use the plastic substrate. Is. In this respect, the other switching element includes a metal-insulator-metal nonlinear resistance element (Meta
l InsulatorMetal), the maximum temperature is 100 ° C to 180 ° C.
It may be applicable to plastic substrates such as polyarylate, polyether sulfone or polysulfone.

Here, a conventional MIM type active matrix type liquid crystal display device will be described.

A conventional MIM type active matrix type liquid crystal display device of this type is disclosed in, for example, Japanese Patent Laid-Open No. 58-1.
As described in Japanese Patent No. 78320, tantalum (Ta) is sputtered on a glass substrate, the tantalum is anodized in citric acid to form tantalum oxide, and chromium (Cr) or gold (Au) is deposited on the tantalum oxide. And the like, and then processed by dry etching.

[0006] However, such Japanese Patent Laid-Open No. 58-1
In the MIM manufacturing method described in Japanese Patent No. 78320, when a substrate is made of plastic, a thin pattern of a metal film having a large film stress such as Ta has to be formed on the substrate, and it is difficult to maintain adhesion. Moreover, since dry etching is often used for processing the film, there is a problem that plasma may damage the plastic substrate.

The present invention has been made in view of the above problems, and provides an active matrix type liquid crystal display device using a non-linear resistance element having a metal-insulator-metal using a plastic substrate as a switching element. With the goal.

[0008]

According to another aspect of the present invention, there is provided a liquid crystal display device comprising: two translucent plastic substrates facing each other with a gap; and a liquid crystal layer sandwiched between the translucent plastic substrates. A liquid crystal driving transparent electrode provided on the translucent plastic substrate; a first conductor connected to the liquid crystal driving transparent electrode; a non-linear resistance film made of an oxide of the first conductor; and a second conductor. A nonlinear resistance element provided, an inorganic oxide layer interposed between the light-transmissive plastic substrate and the first conductor, and a first resistive element interposed between the first conductor and the inorganic oxide layer. And an oxide layer made of a conductor oxide.

A liquid crystal display device according to a second aspect is the first aspect.
In the liquid crystal display device described above, the inorganic oxide layer is an inorganic oxide in which the generation energy of the oxide is smaller than that of the oxide of the first conductor.

According to a third aspect of the present invention, there is provided a liquid crystal display device, wherein two transparent plastic substrates facing each other with a gap, a liquid crystal layer sandwiched between the transparent plastic substrates, and the transparent plastic substrate. And a first conductor connected to the liquid crystal driving transparent electrode.
A non-linear resistance film made of an oxide of a first conductor, a non-linear resistance element having a second conductor, the translucent plastic substrate and the translucent plastic substrate interposed between the first conductor and oxygen atoms. And an inorganic oxide layer bonded by the chemical bond of.

According to another aspect of the liquid crystal display device of the present invention, two translucent plastic substrates facing each other with a gap, a liquid crystal layer sandwiched between these translucent plastic substrates, and the translucent plastic substrate. A transparent electrode for driving a liquid crystal provided in the liquid crystal display device, a first conductor connected to the transparent electrode for driving a liquid crystal, a non-linear resistance film made of an oxide of the first conductor, and a non-linear resistance element including a second conductor. A nitride comprising an inorganic nitride layer interposed between the translucent plastic substrate and a first conductor, and a nitride of the first conductor interposed between the first conductor and the inorganic nitride layer And a physical layer.

The liquid crystal display device according to claim 5 is the liquid crystal display device according to claim 4.
In the liquid crystal display device described above, the inorganic nitride layer is an inorganic nitride having a nitride generation energy smaller than that of the nitride of the first conductor.

According to another aspect of the liquid crystal display device of the present invention, two translucent plastic substrates facing each other with a gap, a liquid crystal layer sandwiched between these translucent plastic substrates, and the translucent plastic substrate. A transparent electrode for driving a liquid crystal provided in the liquid crystal display device, a first conductor connected to the transparent electrode for driving a liquid crystal, a non-linear resistance film made of an oxide of the first conductor, and a non-linear resistance element including a second conductor. And an inorganic nitride layer interposed between the transparent plastic substrate and the first conductor and bonded to the transparent plastic substrate by a chemical bond of nitrogen atoms.

According to another aspect of the liquid crystal display device of the present invention, two translucent plastic substrates facing each other with a gap, a liquid crystal layer sandwiched between the translucent plastic substrates, and the translucent plastic substrate. And a first conductor connected to the liquid crystal driving transparent electrode.
A non-linear resistance film made of an oxide of a first conductor, a non-linear resistance element including a second conductor, an inorganic carbide layer interposed between the translucent plastic substrate and the first conductor, and the first And a carbide layer of the first conductor interposed between the conductor and the inorganic carbide layer.

The liquid crystal display device according to claim 8 is the liquid crystal display device according to claim 7.
In the liquid crystal display device described above, the inorganic carbide layer is an inorganic carbide in which the formation energy of the carbide is smaller than the formation energy of the carbide of the first conductor.

According to a ninth aspect of the present invention, there is provided a method of manufacturing a liquid crystal display device, wherein two translucent plastic substrates facing each other with a gap therebetween, a liquid crystal layer sandwiched between the translucent plastic substrates, and the translucent plastic substrate. Liquid crystal driving transparent electrode provided on a flexible plastic substrate, and a first conductor connected to the liquid crystal driving transparent electrode-a non-linear resistance film made of an oxide of the first conductor-a non-linear circuit including a second conductor A step of forming an inorganic thin film on the surface of the one translucent plastic substrate including a resistance element, a first conductor containing a component of the inorganic thin film, and a first conductor on the inorganic thin film. And a step of forming.

According to a tenth aspect of the present invention, there is provided a method of manufacturing a liquid crystal display device, wherein two translucent plastic substrates facing each other with a gap therebetween, a liquid crystal layer sandwiched between the translucent plastic substrates, and the translucent plastic substrate Liquid crystal driving transparent electrode provided on a flexible plastic substrate, and a first conductor connected to the liquid crystal driving transparent electrode-a non-linear resistance film made of an oxide of the first conductor-a non-linear circuit including a second conductor A step of forming an inorganic thin film on the surface of the one transparent plastic substrate, a step of forming the first conductor on the inorganic thin film, and after forming the first conductor. And a step of forming a first conductor containing a component of the inorganic thin film by heat treatment between the inorganic thin film and the first conductor.

A method of manufacturing a liquid crystal display device according to claim 11, wherein two transparent plastic substrates facing each other with a gap therebetween, a liquid crystal layer sandwiched between the transparent plastic substrates, and the transparent substrate. Liquid crystal driving transparent electrode provided on a flexible plastic substrate, and a first conductor connected to the liquid crystal driving transparent electrode-a non-linear resistance film made of an oxide of the first conductor-a non-linear circuit including a second conductor A step of subjecting the surface of the one translucent plastic substrate to glow discharge treatment in an oxygen atmosphere, a step of forming an inorganic oxide film after the glow discharge treatment, and forming this inorganic oxide film. And a step of forming the first conductor later.

According to a twelfth aspect of the present invention, in the method of manufacturing a liquid crystal display device, two translucent plastic substrates facing each other with a gap, a liquid crystal layer sandwiched between these translucent plastic substrates, and the translucent light Liquid crystal driving transparent electrode provided on a flexible plastic substrate, and a first conductor connected to the liquid crystal driving transparent electrode-a non-linear resistance film made of an oxide of the first conductor-a non-linear circuit including a second conductor A step of subjecting the surface of the one translucent plastic substrate to glow discharge treatment in a nitrogen atmosphere, a step of forming an inorganic nitride film after the glow discharge treatment, and forming this inorganic nitride film. And a step of forming a first conductor later.

[0020]

According to the present invention, when a non-linear resistance element having a first conductor, a non-linear resistance film made of an oxide of the first conductor, and a second conductor is formed on a transparent plastic substrate, By interposing the inorganic thin film between the conductor 1 and the transparent plastic substrate, the first conductor having large internal stress and poor adhesion to the transparent plastic substrate also adheres to the inorganic thin film. Can be adhered to the translucent plastic substrate through the inorganic thin film, and the plastic can be prevented from being damaged during patterning.

[0021]

DESCRIPTION OF THE PREFERRED EMBODIMENTS A liquid crystal display device according to an embodiment of the present invention will be described below with reference to the drawings.

As shown in FIG. 1, a transparent plastic substrate such as polyvinyl alcohol is used to prevent moisture,
An inorganic thin film 2, which is an inorganic oxide layer of silicon oxide (SiO ₂ ), is formed on a 0.5-mm-thick polysulfone substrate 1 that has been subjected to oxygen resistance treatment.
Lower electrode 3 of tantalum (Ta), which is a conductor of, a nonlinear resistance film 4 made of tantalum oxide (Ta ₂ O ₅ ) obtained by oxidizing the lower electrode 3, and titanium (Ti), which is a second conductor. A non-linear resistance element (Metal Insulato) having a first conductor having an upper electrode 5, an insulator, and a second conductor.
r Metal) 6 is formed.

The nonlinear resistance element 6 and the inorganic thin film 2 are also included.
An oxide layer 7 made of tantalum oxide (Ta ₂ O ₅ ) is formed between them.

Further, a liquid crystal driving transparent electrode 8 made of a transparent conductive film of ITO (Indium TinOxide) is formed on the inorganic thin film 2 so as to partially overlap with the upper electrode 5, and an alignment film 9 is formed thereon. The matrix array substrate 10 is formed by being formed.

On the other hand, similarly, a 0.5 mm-thick polysulfone substrate 11 as a translucent plastic substrate, which is moisture-proofed and oxygen-proofed with, for example, polyvinyl alcohol, is placed on an inorganic oxide layer of silicon oxide (SiO ₂ ). The inorganic thin film 12 is formed, and the metallic IT is formed on the inorganic thin film 12.
A counter electrode 13 such as O is formed, and an alignment film 14 is laminated on the counter electrode 13 to form a counter substrate 15.

Then, the matrix array substrate 10 and the counter substrate 15 are opposed to each other with a gap, and the liquid crystal layer 16 is enclosed and sandwiched between the matrix array substrate 10 and the counter substrate 15 to form a liquid crystal cell 17 as a liquid crystal display device. are doing.

Next, the manufacturing method of the above embodiment will be described.

First, as shown in FIG. 2, 0.5, which has been subjected to moisture-proof and oxygen-proof treatment with, for example, polyvinyl alcohol or the like.
5 mm by low temperature sputtering on a polysulfone substrate 1 with a thickness of mm.
A SiO ₂ film of 00 Å is formed as the inorganic thin film 2, and a metal thin film 21 made of Ta of 2000 Å is formed by the sputtering method. Next, this metal thin film 21 is heat-treated at 180 ° C. to form a Ta oxide layer 22 between the metal thin film 21 and the inorganic thin film 2. Then, a positive type photoresist, that is, a photosensitive resin is applied over the entire surface of the metal thin film 21, exposed using a photomask, and developed to form a resist pattern 23.

Subsequently, as shown in FIG. 3, the metal thin film 21 and the oxide layer 22 are etched by the chemical dry etching method to form the oxide layer 7 and the lower electrode 3.
Here, etching is performed in plasma in which CF ₄ and O ₂ gases are mixed in equal amounts, and a taper shape is formed around the pattern, that is, the so-called edge portion. At this time, the presence of the inorganic thin film 2 does not damage the polysulfone substrate 1. Subsequently, with the resist pattern 23 removed, the lower electrode 3 was used as an anode, the platinum mesh plate was used as a cathode, and an electrolyte solution was prepared.
The nonlinear resistance film 4 is formed to a desired thickness on the surface of the lower electrode 3 by performing chemical formation in a weight% ammonium borate aqueous solution and controlling the voltage at this time. In the embodiment, a voltage of 48 V is applied to obtain the 800 Å nonlinear resistance film 4. Further, when Ta is exposed to the electrolytic solution, Ta having a film thickness of 320 Å is Ta ₂ O ₅ having a film thickness of 800 Å.
Changes to

Next, as shown in FIG. 4, a thin film 24 of titanium (Ti) having a film thickness of 1200 angstrom is formed on the entire surface by a sputtering method. A positive type photoresist is applied over the entire surface of the thin film 24, exposed using a photomask, and developed to form a resist pattern 25. Subsequently, 9 g of EDTA (ethylenediamine-tetra-acetic acid), 400 cc of water, 216 cc of hydrogen peroxide and 30 ml of ammonia water were mixed and kept at room temperature to etch the thin film 24, remove the resist, and remove the upper electrode 5. Is formed.

Further, as shown in FIG. 5, a transparent conductive film 26 made of ITO of 1000 angstrom is formed by a sputtering method, and then a positive type photoresist is applied on the entire surface of the transparent electrode film 26, and then a photomask is used. It is exposed to light and developed to form a resist pattern 27.

Then, as shown in FIG. 6, a liquid crystal of the same shape as the resist pattern 27 is driven by an etching solution in which water, hydrochloric acid and nitric acid are mixed at a volume ratio of 1: 1: 0.1 and heated at 30 ° C. The transparent electrode 8 is formed, and the matrix array substrate 10 is formed.

Further, the alignment film 9 made of polyimide resin is applied to the element formation surface of the matrix array substrate 10, baked and rubbed to regulate the liquid crystal alignment direction.

On the other hand, an inorganic thin film is formed on the polysulfone substrate 11.
12 and the counter electrode 13 are formed to form the counter substrate 15, and the alignment film 14 made of polyimide resin or the like is applied to this surface, baked, and rubbed in a direction twisted by about 90 ° with respect to the matrix array substrate 10. This regulates the liquid crystal alignment direction.

The matrix array substrate 10 and the counter substrate 15 are arranged such that the liquid crystal layer 16 has a molecular major axis direction of about 90 °.
A liquid crystal is injected into the liquid crystal layer 16 to form a liquid crystal cell 17 while the liquid crystal is injected so as to be twisted and held at a distance of 5 to 10 μm. Further, a polarizing plate is arranged outside the liquid crystal cell 17 with the polarization axis twisted by about 90 °.

Next, another embodiment will be described. The shape is the same as that of the above-described embodiment shown in FIGS.

Also in this case, as shown in FIG. 1, silicon carbide (SiC) is formed on a 0.4 mm-thick polycarbonate substrate 1 as a translucent plastic substrate that has been moisture-proofed and oxygen-proofed with, for example, polyvinyl alcohol. An inorganic thin film 2 that is an inorganic carbide layer is formed, and a lower electrode 3 of tantalum (Ta) that is a first conductor and tantalum oxide (Ta ₂₎ obtained by oxidizing the lower electrode 3 are formed on the inorganic thin film _2.
O ₅ ), and a nonlinear resistance element (Meta) having a first conductor-insulator-second conductor having a nonlinear resistance film 4 made of O ₅ ) and an upper electrode 5 made of titanium (Ti) which is a second conductor.
l Insulator Metal) 6 is formed.

Further, the nonlinear resistance element 6 and the inorganic thin film 2
An oxide layer 7 made of tantalum oxide (Ta ₂ O ₅ ) is formed between them.

Further, a liquid crystal driving transparent electrode 8 made of a transparent conductive film of ITO (Indium TinOxide) is formed on the inorganic thin film 2 so as to partially overlap the upper electrode 5, and as shown in FIG. An alignment film 9 is formed on the above to form a matrix array substrate 10.

On the other hand, similarly, a 0.5 mm-thick polycarbonate substrate 11 as a translucent plastic substrate, which has been moisture-proofed and oxygen-proofed with, for example, polyvinyl alcohol.
An inorganic thin film 12, which is an inorganic oxide layer of silicon oxide (SiO ₂ ), is formed on the upper surface of the inorganic thin film 12.
A counter electrode 13 such as TO is formed, and an alignment film 14 is laminated on the counter electrode 13 to form a counter substrate 15.

Then, the matrix array substrate 10 and the counter substrate 15 are opposed to each other with a gap, and the liquid crystal layer 16 is enclosed and sandwiched between the matrix array substrate 10 and the counter substrate 15 to form a liquid crystal cell 17 as a liquid crystal display device. are doing.

Next, the manufacturing method of the above embodiment will be described.

First, as shown in FIG. 2, 0.4 that has been subjected to moisture-proof and oxygen-proof treatment with, for example, polyvinyl alcohol.
A 300 angstrom SiC film is formed as an inorganic thin film 2 by low temperature sputtering on a polycarbonate substrate 1 having a thickness of mm, and a metal thin film 21 made of Ta of 1500 angstrom is formed by a sputtering method. Next, this metal thin film 21 is heat-treated at 180 ° C. to form a carbonized layer 22 of Ta in the middle of the metal thin film 21 and the inorganic thin film 2. Then, a positive type photoresist, that is, a photosensitive resin is applied over the entire surface of the metal thin film 21, exposed using a photomask, and developed to form a resist pattern 23.

Subsequently, as shown in FIG. 3, the metal thin film 21 and the oxide layer 22 are etched by the chemical dry etching method to form the oxide layer 7 and the lower electrode 3.
Here, etching is performed in plasma in which CF ₄ and O ₂ gases are mixed in equal amounts, and a taper shape is formed around the pattern, that is, the so-called edge portion. At this time, the polycarbonate substrate 1 is not damaged by the presence of the inorganic thin film 2. Continued
With the resist pattern 23 removed, the lower electrode 3 is used as an anode, the platinum mesh plate is used as a cathode, and formation is performed in an aqueous solution of 1% by weight ammonium borate as an electrolytic solution. By controlling the voltage at this time, the lower electrode is controlled. A non-linear resistance film 4 is formed on the surface of No. 3 with a desired thickness. In the embodiment, a voltage of 48 V is applied to form the 800 Å nonlinear resistance film 4. Further, with respect to the electrolyte solution, the Ta is exposed, thickness 320 Å Ta is the thickness 800 Å Ta ₂
Change to O ₅ .

Next, as shown in FIG. 4, a thin film 24 made of titanium (Ti) having a film thickness of 1000 angstrom is formed on the entire surface by a sputtering method. A positive type photoresist is applied over the entire surface of the thin film 24, exposed using a photomask, and developed to form a resist pattern 25. Subsequently, 9 g of EDTA (ethylenediamine-tetra-acetic acid), 400 cc of water, 216 cc of hydrogen peroxide and 30 ml of ammonia water were mixed and kept at room temperature to etch the thin film 24, remove the resist, and remove the upper electrode 5. Is formed.

Further, as shown in FIG. 5, a transparent conductive film 26 made of ITO having a thickness of 800 Å is formed by a sputtering method, and then a positive type photoresist is applied on the entire surface of the transparent electrode film 26, and then a photomask is used. It is exposed to light and developed to form a resist pattern 27.

Then, as shown in FIG. 6, a liquid crystal of the same shape as the resist pattern 27 is driven by an etching solution in which water, hydrochloric acid and nitric acid are mixed at a volume ratio of 1: 1: 0.1 and heated at 30 ° C. The transparent electrode 8 is formed, and the matrix array substrate 10 is formed.

Further, the alignment film 9 made of polyimide resin is applied to the element formation surface of the matrix array substrate 10, baked and rubbed to regulate the liquid crystal alignment direction.

On the other hand, an inorganic thin film 12 and a counter electrode 13 are formed on a polycarbonate substrate 11 to form a counter substrate 15,
Alignment film 14 made of polyimide resin or the like is applied to this surface,
The liquid crystal alignment direction is regulated by firing and rubbing in a direction twisted by about 90 ° with respect to the matrix array substrate 10.

Then, similarly to the above-mentioned embodiment, the liquid crystal cell 17 is constructed as shown in FIG.

Another embodiment will be described. In this case as well, the shape is the same as that of the above-described embodiment shown in FIGS. 1 to 6.

Also in this case, as shown in FIG. 1, silicon nitride (SiN) is formed on a 0.45 mm-thick polycarbonate substrate 1 as a translucent plastic substrate that has been moisture-proofed and oxygen-proofed with, for example, polyvinyl alcohol. An inorganic thin film 2 which is an inorganic nitride layer is formed.
A tantalum (Ta) lower electrode 3 serving as a first conductor and a tantalum oxide (Ta ₂₎ obtained by oxidizing the lower electrode 3 are provided on the upper side.
O ₅ ), and a nonlinear resistance element (Meta) having a first conductor-insulator-second conductor having a nonlinear resistance film 4 made of O ₅ ) and an upper electrode 5 made of titanium (Ti) which is a second conductor.
l Insulator Metal) 6 is formed.

Further, the nonlinear resistance element 6 and the inorganic thin film 2
An oxide layer 7 made of tantalum oxide (Ta ₂ O ₅ ) is formed between them.

Further, a liquid crystal driving transparent electrode 8 made of a transparent conductive film of ITO (Indium TinOxide) is formed on the inorganic thin film 2 so as to partially overlap the upper electrode 5, and as shown in FIG. An alignment film 9 is formed on the above to form a matrix array substrate 10.

On the other hand, similarly, a 0.5 mm-thick polycarbonate substrate 11 as a translucent plastic substrate, which has been moisture-proofed and oxygen-proofed with, for example, polyvinyl alcohol.
An inorganic thin film 12, which is an inorganic oxide layer of silicon oxide (SiO ₂ ), is formed on the upper surface of the inorganic thin film 12.
A counter electrode 13 such as TO is formed, and an alignment film 14 is laminated on the counter electrode 13 to form a counter substrate 15.

Then, the matrix array substrate 10 and the counter substrate 15 are opposed to each other with a gap, and the liquid crystal layer 16 is enclosed and sandwiched between the matrix array substrate 10 and the counter substrate 15 to form a liquid crystal cell 17 as a liquid crystal display device. are doing.

Next, the manufacturing method of the above embodiment will be described.

First, as shown in FIG. 2, 0.4 which has been subjected to moisture-proof / oxygen-proof treatment with, for example, polyvinyl alcohol or the like.
A 700 Å SiN film is formed as an inorganic thin film 2 by low temperature sputtering on a polycarbonate substrate 1 having a thickness of 5 mm, and a metal thin film 21 of 1500 Å Ta is formed by a sputtering method. Next, this metal thin film 21 is heat-treated at 180 ° C. to form a carbonized layer 22 of Ta in the middle of the metal thin film 21 and the inorganic thin film 2. And
A positive type photoresist, that is, a photosensitive resin is applied over the entire surface of the metal thin film 21, exposed by using a photomask, and developed to form a resist pattern 23.

Subsequently, as shown in FIG. 3, the metal thin film 21 and the oxide layer 22 are etched by the chemical dry etching method to form the oxide layer 7 and the lower electrode 3.
Here, etching is performed in plasma in which CF ₄ and O ₂ gases are mixed in equal amounts, and a taper shape is formed around the pattern, that is, the so-called edge portion. At this time, the polycarbonate substrate 1 is not damaged by the presence of the inorganic thin film 2. Continued
With the resist pattern 23 removed, the lower electrode 3 is used as an anode, the platinum mesh plate is used as a cathode, and formation is performed in an aqueous solution of 1% by weight ammonium borate as an electrolytic solution. By controlling the voltage at this time, the lower electrode is controlled. A non-linear resistance film 4 is formed on the surface of No. 3 with a desired thickness. In the embodiment, a voltage of 48 V is applied to form the 800 Å nonlinear resistance film 4. Further, with respect to the electrolyte solution, the Ta is exposed, thickness 320 Å Ta is the thickness 800 Å Ta ₂
Change to O ₅ .

Next, as shown in FIG. 4, a thin film 24 made of titanium (Ti) having a film thickness of 1000 angstrom is formed on the entire surface by a sputtering method. A positive type photoresist is applied over the entire surface of the thin film 24, exposed using a photomask, and developed to form a resist pattern 25. Subsequently, 9 g of EDTA (ethylenediamine-tetra-acetic acid), 400 cc of water, 216 cc of hydrogen peroxide and 30 ml of ammonia water were mixed and kept at room temperature to etch the thin film 24, remove the resist, and remove the upper electrode 5. Is formed.

Further, as shown in FIG. 5, a transparent conductive film 26 made of ITO having a thickness of 800 Å is formed by a sputtering method, and then a positive type photoresist is applied on the entire surface of the transparent electrode film 26, and then a photomask is used. It is exposed to light and developed to form a resist pattern 27.

Then, as shown in FIG. 6, a liquid crystal of the same shape as the resist pattern 27 is driven by an etching solution prepared by mixing water, hydrochloric acid and nitric acid in a volume ratio of 1: 1: 0.1 and heating at 30 ° C. The transparent electrode 8 is formed, and the matrix array substrate 10 is formed.

Further, the alignment film 9 made of polyimide resin is applied to the element formation surface of the matrix array substrate 10, baked and rubbed to regulate the liquid crystal alignment direction.

On the other hand, the inorganic thin film 12 and the counter electrode 13 are formed on the polycarbonate substrate 11 to form the counter substrate 15,
Alignment film 14 made of polyimide resin or the like is applied to this surface,
The liquid crystal alignment direction is regulated by firing and rubbing in a direction twisted by about 90 ° with respect to the matrix array substrate 10.

Then, similarly to the above-mentioned embodiment, the liquid crystal cell 17 is constructed as shown in FIG.

Further, another embodiment will be described. In this case as well, the shape is the same as that of the above-described embodiment shown in FIGS. 1 to 6.

Also in this case, as shown in FIG. 1, 0.5 mm
An inorganic thin film 2 that is an inorganic oxide layer is formed on a thick polycarbonate substrate 1, and a lower electrode 3 of tantalum (Ta) that is a first conductor and the lower electrode 3 are oxidized on the inorganic thin film 2. The non-linear resistance film 4 made of tantalum oxide (Ta ₂ O ₅ ) and the titanium (T
i) A non-linear resistance element (Metal Insulator Me) including a first conductor having an upper electrode 5, an insulator, and a second conductor.
tal) 6 is formed.

Further, the nonlinear resistance element 6 and the inorganic thin film 2
An oxide layer 7 made of tantalum oxide (Ta ₂ O ₅ ) is formed between them.

Further, a liquid crystal driving transparent electrode 8 made of a transparent conductive film of ITO (Indium TinOxide) is formed on the inorganic thin film 2 so as to partially overlap with the upper electrode 5, and as shown in FIG. An alignment film 9 is formed on the above to form a matrix array substrate 10.

On the other hand, similarly, a 0.5 mm-thick polycarbonate substrate 11 as a translucent plastic substrate which has been moisture-proofed and oxygen-proofed with, for example, polyvinyl alcohol.
An inorganic thin film 12, which is an inorganic oxide layer of silicon oxide (SiO ₂ ), is formed on the upper surface of the inorganic thin film 12.
A counter electrode 13 such as TO is formed, and an alignment film 14 is laminated on the counter electrode 13 to form a counter substrate 15.

Then, the matrix array substrate 10 and the counter substrate 15 are opposed to each other with a gap, and the liquid crystal layer 16 is enclosed and sandwiched between the matrix array substrate 10 and the counter substrate 15 to form a liquid crystal cell 17 as a liquid crystal display device. are doing.

Next, the manufacturing method of the above embodiment will be described.

First, as shown in FIG. 2, a 0.5 mm thick polycarbonate substrate 1 was subjected to an oxygen glow discharge treatment by causing a discharge in 1 Pa of oxygen to form an inorganic thin film 2, and Ta _{2 of} 500 angstrom was formed. O ₅ film is an oxide layer 22
Then, a metal thin film 21 made of Ta of 2000 angstrom is formed by the sputtering method. Then, a positive type photoresist, that is, a photosensitive resin is applied over the entire surface of the metal thin film 21, exposed using a photomask, and developed to form a resist pattern 23.

Subsequently, as shown in FIG. 3, the metal thin film 21 and the oxide layer 22 are etched by the chemical dry etching method to form the oxide layer 7 and the lower electrode 3.
Here, etching is performed in plasma in which CF ₄ and O ₂ gases are mixed in equal amounts, and a taper shape is formed around the pattern, that is, the so-called edge portion. At this time, the polycarbonate substrate 1 is not damaged by the presence of the inorganic thin film 2. Continued
With the resist pattern 23 removed, the lower electrode 3 is used as an anode, the platinum mesh plate is used as a cathode, and formation is performed in an aqueous solution of 1% by weight ammonium borate as an electrolytic solution. By controlling the voltage at this time, the lower electrode is controlled. A non-linear resistance film 4 is formed on the surface of No. 3 with a desired thickness. In the embodiment, a voltage of 48 V is applied to form the 800 Å nonlinear resistance film 4. Further, with respect to the electrolyte solution, the Ta is exposed, thickness 320 Å Ta is the thickness 800 Å Ta ₂
Change to O ₅ .

Next, as shown in FIG. 4, a thin film 24 of titanium (Ti) having a film thickness of 1200 angstrom is formed on the entire surface by a sputtering method. A positive type photoresist is applied over the entire surface of the thin film 24, exposed using a photomask, and developed to form a resist pattern 25. Subsequently, 9 g of EDTA (ethylenediamine-tetra-acetic acid), 400 cc of water, 216 cc of hydrogen peroxide and 30 ml of ammonia water were mixed and kept at room temperature to etch the thin film 24, remove the resist, and remove the upper electrode 5. Is formed.

Further, as shown in FIG. 5, a transparent conductive film 26 made of ITO of 1000 angstrom is formed by a sputtering method, and then a positive type photoresist is applied on the entire surface of the transparent electrode film 26, and then a photomask is used. It is exposed to light and developed to form a resist pattern 27.

Then, as shown in FIG. 6, a liquid crystal of the same shape as the resist pattern 27 is driven by an etching solution prepared by mixing water, hydrochloric acid and nitric acid in a volume ratio of 1: 1: 0.1 and heating at 30 ° C. The transparent electrode 8 is formed, and the matrix array substrate 10 is formed.

Further, by aligning the alignment film 9 made of polyimide resin on the element formation surface of the matrix array substrate 10, firing and rubbing, the liquid crystal alignment direction is regulated.

On the other hand, the inorganic thin film 12 and the counter electrode 13 are formed on the polycarbonate substrate 11 to form the counter substrate 15,
Alignment film 14 made of polyimide resin or the like is applied to this surface,
The liquid crystal alignment direction is regulated by firing and rubbing in a direction twisted by about 90 ° with respect to the matrix array substrate 10.

Then, similarly to the above-mentioned embodiment, the liquid crystal cell 17 is constructed as shown in FIG.

Furthermore, another embodiment will be described. In this case as well, the shape is similar to that shown in FIGS.
Is the same as the above-mentioned embodiment shown in FIG.

Also in this case, as shown in FIG. 1, 0.4 mm
An inorganic thin film 2 which is an inorganic nitride layer is formed on a thick polysulfone substrate 1, and a lower electrode 3 of tantalum (Ta) which is a first conductor and an oxidation of the lower electrode 3 are formed on the inorganic thin film 2. The non-linear resistance film 4 made of tantalum oxide (Ta ₂ O ₅ ) and the titanium (T
i) A non-linear resistance element (Metal Insulator Me) including a first conductor having an upper electrode 5, an insulator, and a second conductor.
tal) 6 is formed.

Further, the nonlinear resistance element 6 and the inorganic thin film 2
An oxide layer 7 made of tantalum oxide (Ta ₂ O ₅ ) is formed between them.

Further, a liquid crystal driving transparent electrode 8 made of a transparent conductive film of ITO (Indium Tin Oxide) is formed on the inorganic thin film 2 so as to be partially overlapped with the upper electrode 5, and as shown in FIG. An alignment film 9 is formed on the above to form a matrix array substrate 10.

On the other hand, similarly, a 0.5 mm-thick polycarbonate substrate 11 as a translucent plastic substrate, which has been moisture-proofed and oxygen-proofed with, for example, polyvinyl alcohol.
An inorganic thin film 12, which is an inorganic oxide layer of silicon oxide (SiO ₂ ), is formed on the upper surface of the inorganic thin film 12.
A counter electrode 13 such as TO is formed, and an alignment film 14 is laminated on the counter electrode 13 to form a counter substrate 15.

Then, the matrix array substrate 10 and the counter substrate 15 are opposed to each other with a gap, and the liquid crystal layer 16 is enclosed and sandwiched between the matrix array substrate 10 and the counter substrate 15 to form a liquid crystal cell 17 as a liquid crystal display device. are doing.

Next, the manufacturing method of the above embodiment will be described.

First, as shown in FIG. 2, a polysulfone substrate 1 having a thickness of 0.4 mm was subjected to a nitrogen glow discharge treatment by causing an electric discharge in nitrogen of 1 Pa to form an inorganic thin film 2, which was sputtered at a low temperature of 300 angstroms. Ta ₂ O
_An inorganic thin film layer 22 is formed from ₅ films, and a metal thin film 21 made of Ta of 1500 angstrom is formed by a sputtering method. Then, a positive type photoresist, that is, a photosensitive resin is applied over the entire surface of the metal thin film 21, exposed using a photomask, and developed to form a resist pattern 23.

Subsequently, as shown in FIG. 3, the metal thin film 21 and the oxide layer 22 are etched by the chemical dry etching method to form the oxide layer 7 and the lower electrode 3.
Here, etching is performed in plasma in which CF ₄ and O ₂ gases are mixed in equal amounts, and a taper shape is formed around the pattern, that is, the so-called edge portion. At this time, the polycarbonate substrate 1 is not damaged by the presence of the inorganic thin film 2. Continued
With the resist pattern 23 removed, the lower electrode 3 is used as an anode, the platinum mesh plate is used as a cathode, and chemical formation is performed in an aqueous solution of 1% by weight ammonium borate as an electrolytic solution. By controlling the voltage at this time, the lower electrode is controlled. A non-linear resistance film 4 is formed on the surface of No. 3 with a desired thickness. In the embodiment, a voltage of 48 V is applied to form the 800 Å nonlinear resistance film 4. Further, with respect to the electrolyte solution, the Ta is exposed, thickness 320 Å Ta is the thickness 800 Å Ta ₂
Change to O ₅ .

Next, as shown in FIG. 4, a thin film 24 made of titanium (Ti) having a film thickness of 1200 Å is formed on the entire surface by a sputtering method. A positive type photoresist is applied over the entire surface of the thin film 24, exposed using a photomask, and developed to form a resist pattern 25. Subsequently, 9 g of EDTA (ethylenediamine-tetra-acetic acid), 400 cc of water, 216 cc of hydrogen peroxide and 30 ml of ammonia water were mixed and kept at room temperature to etch the thin film 24, remove the resist, and remove the upper electrode 5. Is formed.

Further, as shown in FIG. 5, a transparent conductive film 26 made of ITO of 1000 angstrom is formed by a sputtering method, and then a positive type photoresist is applied on the entire surface of the transparent electrode film 26, and then a photomask is used. It is exposed to light and developed to form a resist pattern 27.

Then, as shown in FIG. 6, a liquid crystal of the same shape as the resist pattern 27 is driven by an etching solution prepared by mixing water, hydrochloric acid and nitric acid in a volume ratio of 1: 1: 0.1 and heating at 30 ° C. The transparent electrode 8 is formed, and the matrix array substrate 10 is formed.

The alignment film 9 made of polyimide resin is applied to the element formation surface of the matrix array substrate 10, baked and rubbed to regulate the liquid crystal alignment direction.

On the other hand, the inorganic thin film 12 and the counter electrode 13 are formed on the polycarbonate substrate 11 to form the counter substrate 15,
Alignment film 14 made of polyimide resin or the like is applied to this surface,
The liquid crystal alignment direction is regulated by firing and rubbing in a direction twisted by about 90 ° with respect to the matrix array substrate 10.

Then, similarly to the above-mentioned embodiment, the liquid crystal cell 17 is constructed as shown in FIG.

The same effects can be obtained by using any of the well-known transparent plastics such as polyether sulfone, polyarylate or polycarbonate for the transparent plastic substrates 1 and 11.

The lower electrode 3 forming the linear resistance element 6 is generally made of Ta, an alloy thereof, or a refractory metal of the same family, and these have a large internal stress of the film and are transparent to light having different surface properties. Inorganic thin film 2 such as an inorganic oxide film, an inorganic nitride film, an inorganic carbonized film containing an organic component element that constitutes the plastic as an inorganic film having a relatively good adhesiveness to the plastic, although the adhesiveness is extremely poor on the plastic 1 By using, the adhesion between the lower electrode 3 and the polysulfone substrate 1 or the polycarbonate substrate 1 is improved.

Further, the oxide layer 7 or the metal and oxygen,
If a mixed composition layer of nitrogen, carbon, etc. is provided between the inorganic thin film 2 and the lower electrode 3, the adhesion without any problems in processing and practical use can be obtained, and the constituent layers such as the nonlinear resistance element 6 can be obtained. Polysulfone substrate 1 when patterning
Alternatively, it is possible to prevent the polycarbonate substrate 1 from being damaged. This layer can be formed by newly forming one having such a composition. To make it simpler, however, the inorganic thin film 2 and the lower electrode 3 are individually laminated and heat-treated to form a metal compound layer therebetween. Is also good. In this case, it is necessary that the formation energy of the compound forming the inorganic compound layer such as oxide, nitride or carbide is smaller than the formation energy of the compound of the lower electrode. For example, when Ta is used as the lower metal, TiO ₂ or SiO ₂
The oxide energy of is less than Ta ₂ O ₅ formation energy, which is preferable.

That is, this is because the chemical bond between atoms forming each layer is weak. Then, in order to make many oxygen bonds bonded to the structural carbon in the plastic exist on the surface, the surface should be exposed to glow discharge, and hydrogen existing on the surface is desorbed. In order to combine oxygen or nitrogen with this oxygen, the discharge atmosphere may be oxygen or nitrogen. After that, an inorganic oxide containing oxygen or nitrogen and having good adhesiveness to the lower electrode 3 constituting the nonlinear resistance element 6, most preferably an oxide of the lower electrode 3, or an inorganic nitride, most preferably nitriding of the lower electrode 3. After forming the object, the non-linear resistance element 6 may be formed.

[0100]

According to the present invention, the first conductor-this first conductor
Non-linear resistance film made of oxide of conductor-When forming a non-linear resistance element having a second conductor on a transparent plastic substrate, an inorganic thin film is interposed between the first conductor and the transparent plastic substrate. By doing so, the first conductor having large internal stress and poor adhesion to the translucent plastic substrate also adheres to the inorganic thin film, so that the first conductor can be adhered to the translucent plastic substrate through the inorganic thin film. Also, the plastic can be prevented from being damaged even when patterning.

[Brief description of drawings]

FIG. 1 is a cross-sectional view showing a liquid crystal display device of an embodiment of the present invention.

FIG. 2 is a cross-sectional view showing one manufacturing process of the above liquid crystal display device.

FIG. 3 is a cross-sectional view showing a next manufacturing step of the above liquid crystal display device shown in FIG.

FIG. 4 is a cross-sectional view showing a next manufacturing step of the above liquid crystal display device shown in FIG.

5 is a cross-sectional view showing the next manufacturing step of the liquid crystal display device shown in FIG. 4 shown in FIG.

FIG. 6 is a cross-sectional view showing the next manufacturing step of the above liquid crystal display device shown in FIG. 5.

[Explanation of symbols]

1 Polysulfone substrate as a transparent plastic substrate, polycarbonate substrate 2 Inorganic thin film as an inorganic oxide layer, inorganic nitride layer or inorganic carbide layer 3 Lower electrode as a first conductor 4 Non-linear resistance film 5 As a second conductor Upper electrode 6 Non-linear resistance element 7 Oxide layer 8 Transparent electrode for driving liquid crystal 11 Polysulfone substrate as a transparent plastic substrate, polycarbonate substrate 16 Liquid crystal layer 17 Liquid crystal cell as liquid crystal display device

Claims (12)

[Claims] 1. Two translucent plastic substrates facing each other with a gap, a liquid crystal layer sandwiched between these translucent plastic substrates, and a liquid crystal driving transparent layer provided on the translucent plastic substrate. An electrode and a first conductor connected to the liquid crystal driving transparent electrode-a first conductor
A non-linear resistance film made of an oxide of a conductor, a non-linear resistance element having a second conductor, an inorganic oxide layer interposed between the light-transmissive plastic substrate and the first conductor, A liquid crystal display device comprising: a conductor and an oxide layer formed of an oxide of the first conductor, the oxide layer being interposed between the conductor and the inorganic oxide layer. 2. The liquid crystal display device according to claim 1, wherein the inorganic oxide layer is an inorganic oxide having an oxide generation energy smaller than that of the oxide of the first conductor. 3. A pair of translucent plastic substrates facing each other with a gap, a liquid crystal layer sandwiched between the translucent plastic substrates, and a liquid crystal driving transparent film formed on the translucent plastic substrate. An electrode and a first conductor connected to the liquid crystal driving transparent electrode-a first conductor
Non-linear resistance film made of oxide of conductor-Non-linear resistance element having second conductor, chemistry of oxygen atom interposed between the light-transmissive plastic substrate and the first conductor A liquid crystal display device, comprising an inorganic oxide layer bonded by bonding. 4. Two translucent plastic substrates facing each other with a gap, a liquid crystal layer sandwiched between these translucent plastic substrates, and a liquid crystal driving transparent layer provided on the translucent plastic substrate. An electrode and a first conductor connected to the liquid crystal driving transparent electrode-a first conductor
Non-linear resistance film made of oxide of conductor-non-linear resistance element having a second conductor, inorganic nitride layer interposed between the light-transmissive plastic substrate and the first conductor, and the first conductor And a nitride layer made of a nitride of the first conductor interposed between the inorganic nitride layers. 5. The liquid crystal display device according to claim 4, wherein the inorganic nitride layer is an inorganic nitride having a nitride generation energy smaller than that of the nitride of the first conductor. 6. Two translucent plastic substrates facing each other with a gap, a liquid crystal layer sandwiched between these translucent plastic substrates, and a liquid crystal driving transparent layer provided on the translucent plastic substrate. An electrode and a first conductor connected to the liquid crystal driving transparent electrode-a first conductor
Non-linear resistance film made of oxide of conductor-Non-linear resistance element having second conductor, chemistry of nitrogen atom interposed between the light-transmissive plastic substrate and the first conductor A liquid crystal display device comprising an inorganic nitride layer bonded by bonding. 7. Two transparent plastic substrates facing each other with a gap, a liquid crystal layer sandwiched between the transparent plastic substrates, and a transparent liquid crystal driving substrate provided on the transparent plastic substrate. An electrode and a first conductor connected to the liquid crystal driving transparent electrode-a first conductor
Non-linear resistance film made of oxide of conductor-non-linear resistance element including second conductor, inorganic carbide layer interposed between the light-transmissive plastic substrate and the first conductor, and the first conductor And a carbide layer of the first conductor interposed between the inorganic carbide layers, and a liquid crystal display device. 8. The liquid crystal display device according to claim 7, wherein the inorganic carbide layer is an inorganic carbide having a carbide formation energy smaller than that of the carbide of the first conductor. 9. Two translucent plastic substrates facing each other with a gap, a liquid crystal layer sandwiched between these translucent plastic substrates, and a liquid crystal driving transparent layer provided on the translucent plastic substrate. An electrode and a first conductor connected to the liquid crystal driving transparent electrode-a first conductor
A non-linear resistance film made of oxide of a conductor of the above-a non-linear resistance element provided with a second conductor, and a step of forming an inorganic thin film on the surface of the one translucent plastic substrate; A method of manufacturing a liquid crystal display device, comprising: a first conductor containing a component of an inorganic thin film; and a step of sequentially forming the first conductor. 10. Two translucent plastic substrates facing each other with a gap, a liquid crystal layer sandwiched between these translucent plastic substrates, and a liquid crystal driving transparent layer provided on the translucent plastic substrate. An electrode and a first conductor connected to the liquid crystal driving transparent electrode-a first conductor
A non-linear resistance film made of an oxide of a conductor of the above-a non-linear resistance element provided with a second conductor, and a step of forming an inorganic thin film on the surface of the one translucent plastic substrate; A step of forming a first conductor; and a step of forming a first conductor containing a component of the inorganic thin film by heat treatment between the inorganic thin film and the first conductor after forming the first conductor. A method for manufacturing a liquid crystal display device, comprising: 11. Two translucent plastic substrates facing each other with a gap, a liquid crystal layer sandwiched between these translucent plastic substrates, and a liquid crystal driving transparent layer provided on the translucent plastic substrate. An electrode and a first conductor connected to the liquid crystal driving transparent electrode-a first conductor
A non-linear resistance film made of an oxide of a conductor of the above-described non-linear resistance element having a second conductor, and the step of performing glow discharge treatment on the surface of the one translucent plastic substrate in an oxygen atmosphere; A method for manufacturing a liquid crystal display device, comprising: a step of forming an inorganic oxide film after the treatment; and a step of forming the first conductor after forming the inorganic oxide film. 12. A pair of translucent plastic substrates facing each other with a gap, a liquid crystal layer sandwiched between these translucent plastic substrates, and a liquid crystal driving transparent layer provided on the translucent plastic substrate. An electrode and a first conductor connected to the liquid crystal driving transparent electrode-a first conductor
A non-linear resistance film made of an oxide of a conductor of the above-described non-linear resistance element having a second conductor, the step of performing glow discharge treatment on the surface of the one transparent plastic substrate in a nitrogen atmosphere, and the glow discharge A method of manufacturing a liquid crystal display device, comprising: a step of forming an inorganic nitride film after the treatment; and a step of forming a first conductor after forming the inorganic nitride film.