JP2989285B2 - Thin film laminated device with substrate - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a thin-film laminated device, and more particularly, to a switching element which can be suitably used for a flat panel display for OA equipment and TV.

[0002]

2. Description of the Related Art There is a strong demand for use of large area liquid crystal panels in OA equipment terminals and liquid crystal TVs. For this reason, a switch is provided for each pixel in the active matrix system so that a voltage is maintained. In recent years, liquid crystal panels have been actively reduced in weight and cost, and the use of plastic for the switching element substrate has been studied. However, when a thin film laminated switching element is formed on plastic, the plastic substrate is deformed or curled, and there is a problem such as film peeling. Also, when fabricating a thin-film laminated switching element, there is a photolithography step of immersing the plastic in a solution of acid, alkali, water, etc.Acid, alkali, water, etc. remain in the plastic, causing the element deterioration. became. When a thin film laminated device is formed into a fine pattern, a pattern shift occurs due to expansion and contraction of a substrate, and it has been difficult to expose a large area at a time. Further, the anisotropy of the expansion and contraction of the substrate made pattern formation more difficult. In the production of a liquid crystal display device using a plastic film substrate, it is necessary to perform an alignment method specific to plastic at the time of alignment treatment. But Si
Japanese Patent Publication No. 47776/1992 discloses that an O ₂ layer is formed on one side of a plastic film so that orientation treatment can be performed in the same manner as a glass substrate.

[0003]

An object of the present invention is to solve the above-mentioned conventional problems, and to provide a thin-film laminated device which is light in weight, low in cost, free of film peeling, curl and the like, and has good reliability.

[0004]

To achieve the above object, the present inventors have:
Investigating the fabrication of switching devices on lightweight and inexpensive plastics and conducting repeated studies, it became clear that curling was the biggest problem in the case of plastic film deformation of the plastic substrate in the device fabrication process. . The inventors found that the causes of plastic deformation and plastic film curl were internal stress of the thin film to be laminated, thermal expansion and contraction of the plastic, swelling with acid, alkali, and water, and the like.
It has been found that it is effective to use a plastic substrate having a thin film of 00 ° formed on both sides. further,
When a thin film laminated device is microfabricated on the above substrate, the stretch anisotropy of the plastic substrate has become a problem. The cause was found to be due to the structural anisotropy of the plastic substrate, and it was found that it was effective to use an amorphous plastic substrate having a thin film made of an inorganic substance and having a thickness of 5000 to 10000 ° on both surfaces. Thus, the present invention has been completed. That is, the present invention provides a thin-film laminated device with a substrate, wherein the substrate is an amorphous plastic in which a thin film made of an inorganic substance is formed on both surfaces of the thin-film laminated device formed on the substrate. About. Further, the transmittance of the amorphous plastic substrate of the thin film laminated device is preferably 80% or more at a wavelength of 400 to 850 nm. The formation of an inorganic substance thin film on a plastic substrate is important for solving problems such as peeling of a thin film laminated device formed thereon. If the thin film is formed only on one side of the plastic substrate (film), curl occurs in accordance with the internal stress of the inorganic material thin film, causing problems such as handling. In order to avoid this, it is important to form an inorganic thin film on both sides of the plastic substrate (film). When the thin film laminated device of the present invention is used for a liquid crystal display driving element, the transmittance of a plastic substrate is set to a wavelength of 400 to 85 in order to secure display contrast.
It is preferably 80% or more at 0 nm. In order to produce the thin film laminated device of the present invention, first, an amorphous plastic such as polyarylate, polyethersulfone, polyetherimide, or polysulfone or SiOx (1 ≦ x ≦ 2) on both surfaces of a plastic film,
Si: O: N, Si: O: H, Si: N: H, Si:
O: N: H, Si ₃ N ₄ , TiO ₂ , ZnS, ZnO,
Al ₂ O ₃ , AlN, MgO, GeO, ZrO ₂ , Nb
An inorganic material selected from the group consisting of ₂ O ₅ , SiC and Ta ₂ O ₅ is formed in a thickness of 300 to 10000 ° by a sputtering method, an evaporation method, a plasma CVD method, or the like. The inorganic substance may be crystalline or amorphous, but amorphous is preferable because it has no stretching anisotropy and there is no intrusion of moisture from the crystal grain boundaries. In order to make these inorganic substances amorphous, the substrate temperature is preferably 200 ° C. or lower, more preferably 150 ° C. or lower, and it is preferable to manufacture them by a sputtering method or a plasma CVD method. The formed thin film does not necessarily need to have the same inorganic substance on both surfaces, and does not need to have the same thickness. Particularly preferred inorganic substances are SiO ₂ , S
i ₃ N ₄ , Si: N: O, Si: O: H, Si: N:
H, Si: O: N: H, AlN and the like. The thickness of the plastic is 50 μm to 2 mm.
It is preferably at most 00 μm, particularly preferably at most 300 μm. The glass transition point of the plastic is 150 ° C. or more, particularly preferably 1
80 ° C. or higher is preferred. Further, a thin film laminated device is formed on a plastic coated on both sides with an inorganic substance. Examples of the thin film laminated device include a MIM element having a metal-insulator-metal layer structure, and an MSI element (Metal-Semi-I) described in JP-A-61-275811.
SIS element having a semiconductor-insulator-semiconductor layer configuration, and a metal-insulator-metal-insulator-metal MIMIM element described in JP-A-64-7577. Among them, an MIM element using a hard carbon film as an insulator is advantageous. When a hard carbon film is used for the insulating layer, the plastic substrate (film) curls greatly. Therefore, it is necessary to form an inorganic material film on both surfaces of the substrate to increase the rigidity of the substrate.

Next, a method for manufacturing the device will be described in detail with reference to FIGS. First, a transparent electrode material for a pixel electrode is deposited on a plastic substrate 1 having both surfaces coated with the inorganic substance (2a, 2b) by a method such as vapor deposition or sputtering, and is patterned into a predetermined pattern. Then, a conductor thin film for a lower electrode is formed by a method such as vapor deposition or sputtering, and is patterned into a predetermined pattern by wet or dry etching to form a first conductor 7 serving as a lower electrode, on which a plasma CVD method and an ion beam method are applied. After the hard carbon film 2 is coated by a method such as dry etching, wet etching or a lift-off method using a resist, a predetermined pattern is formed into an insulating film, and then a conductor thin film for a bus line is formed thereon by a method such as vapor deposition or sputtering. And form a second conductor 6 which becomes a bus line by patterning into a predetermined pattern. And, finally removing the unnecessary portion of the lower electrode, to expose the transparent electrode pattern, and the pixel electrode 4. In this case, the configuration of the MIM element is not limited to this. After the MIM element is manufactured, a transparent electrode is provided on the uppermost layer, a transparent electrode also serves as an upper or lower electrode, a side surface of the lower electrode. To M
Various modifications are possible, such as those in which an IM element is formed.
Here, the thickness of the lower electrode, the upper electrode and the transparent electrode is usually
They are in the range of hundreds to several thousand, several hundred to several thousand, and several hundred to several thousand, respectively. The thickness of the hard carbon film is 100 to 8000, preferably 200 to 6000, more preferably 300.
In the range of Å4000 °. In the case of a plastic substrate, it has been extremely difficult to fabricate an active matrix device using an active element because of its heat resistance. However, a hard carbon film can be produced at a substrate temperature of about room temperature, and a high quality film can be produced on a plastic substrate, which is a very effective means for improving image quality.

Next, the material of the MIM element used in the present invention will be described in more detail. The material of the first conductor 1 serving as the lower electrode includes Al, Ta, Cr, W, Mo, P
t, Ni, Ti, Cu, Au, W, ITO, ZnO: A
Various conductors such as 1, In ₂ O ₃ and SnO ₂ are used.

Next, as the material of the second conductor 3 serving as a bus line, Al, Cr, Ni, Mo, Pt, Ag, Ti,
Cu, Au, W, Ta, ITO, ZnO: Al, In ₂
Although various conductors such as O ₃ and SnO ₂ are used, Ni and P are particularly excellent in stability and reliability of IV characteristics.
t and Ag are preferred. It can be seen that the MIM element using the hard carbon film 2 as the insulating film does not change its symmetry even when the type of the electrode is changed, and that it has a Pool-Frenkel conduction from the relationship of lnI∝√v. Also from this, this kind of M
In the case of the IM device, it can be understood that any combination of the upper electrode and the lower electrode may be used. However, the device characteristics (IV characteristics) are degraded and changed due to the adhesion between the hard carbon film and the electrode and the state of the interface. Considering these, Ni, P
It was found that t and Ag were good. The current-voltage characteristics of the MIM device of the present invention are shown in FIG. 2, and are approximately expressed by the following conduction equation.

[0008]

(Equation 1)

I: current V: applied voltage κ: conductivity coefficient
β: Pool Frenkel coefficient n: Carrier density μ: Carrier mobility q: Electron charge Φ: Trap depth ρ: Specific resistance d: Hard carbon film thickness (Å) k: Boltzmann constant T: Atmospheric temperature ε ₁ : Hard Dielectric constant of carbon ε ₂ : vacuum dielectric constant

The hard carbon film of the present invention will be described in detail. An organic compound gas, especially a hydrocarbon gas, is used to form a hard carbon film. The phase state of these raw materials does not necessarily need to be a gaseous phase at normal temperature and normal pressure, but may be used in a liquid phase or a solid phase as long as it can be vaporized through melting, evaporation, sublimation, etc. by heating or decompression. is there. Examples of the hydrocarbon gas as a raw material gas include paraffinic hydrocarbons such as CH ₄ , C ₂ H ₆ , C ₃ H ₈ , and C ₄ H ₁₀ , acetylene hydrocarbons such as C ₂ H ₂ , and olefinic hydrocarbons. And a gas containing at least all hydrocarbons such as diolefin-based hydrocarbons and aromatic hydrocarbons. Further, other than hydrocarbons, for example,
Alcohols, ketones, ethers, esters, C
Any compound containing at least a carbon element such as O and CO ₂ can be used. As a method for forming a hard carbon film from a source gas in the present invention, a method in which a film forming active species is formed through a plasma state generated by a plasma method using a direct current, a low frequency, a high frequency, or a microwave or the like However, a method utilizing a magnetic field effect is more preferable because deposition is performed under a low pressure for the purpose of increasing the area, improving uniformity, and forming a film at a low temperature. Active species can also be formed by thermal decomposition at high temperatures. In addition, ionization evaporation,
Alternatively, it may be formed through an ion state generated by an ion beam evaporation method or the like, may be formed from neutral particles generated by a vacuum evaporation method, a sputtering method, or the like, and further, a combination thereof. May be formed. An example of the conditions for depositing the hard carbon film thus produced is as follows in the case of the plasma CVD method. RF output: 0.1 to 50 W / cm ² Pressure: 1/10 ^{3 to} 10 Torr Deposition temperature: room temperature to 350 ° C. The raw material gas is decomposed into radicals and ions by this plasma state, and reacts to form carbon on the substrate. Atom C
And a hydrogen atom H, a hard carbon film containing at least one of amorphous (amorphous) and microcrystalline (crystal size is several tens of degrees to several μm) is deposited. Table 1 shows various properties of the hard carbon film.

[0011]

[Table 1]

Note) Measuring method; Specific resistance (ρ): Determined from the IV characteristics of a coplanar cell. Optical band gap (Egopt): The absorption coefficient (α) is determined from the spectral characteristics, and is determined from the relationship of Expression 2.

(Equation 2) Hydrogen content in film [C (H)]: 29 from infrared absorption spectrum
The peak near 00 / cm is integrated and multiplied by the absorption cross section A to obtain the peak. That is, [C (H)] = A · ∫α (v) / V
Dv SP ³ / SP ² ratio: Infrared absorption spectrum was measured using SP ³ , SP ²
Is decomposed into Gaussian functions respectively belonging to the above, and is obtained from the area ratio. Vickers hardness (H): According to a micro Vickers meter. Refractive index (n): Based on ellipsometer. Defect density: by ESR.

The hard carbon film thus formed was analyzed by Raman spectroscopy and IR absorption.
As shown in FIGS. 7 and 7, the carbon atom has a hybrid orbital of SP ³ and SP ²
It has been clarified that interatomic bonds that form hybrid orbitals are mixed. The ratio of SP ³ binding to SP ² binding is
It can be roughly estimated by separating the IR spectrum into peaks. In the IR spectrum, spectra of many modes are overlapped and measured at 2800 to 3150 / cm. The assignment of peaks corresponding to each wave number is clear, and peak separation is performed by Gaussian distribution as shown in FIG. And calculate the respective peak areas and determine the ratio,
P ³ / SP ² can be known. According to X-ray and electron diffraction analyses, it is known that it is in an amorphous state (aC: H) and / or an amorphous state containing fine crystal grains of about 50 ° to several μm. In general, in the case of the plasma CVD method suitable for mass production, the smaller the RF output, the higher the specific resistance and hardness of the film. The lower the pressure, the longer the lifetime of the active species. The area can be made uniform, and the specific resistance and hardness tend to increase. Furthermore, since the plasma density decreases at low pressure, the method utilizing the magnetic field confinement effect is particularly effective for increasing the specific resistance. Further, this method has a feature that a high-quality hard carbon film can be similarly formed even under a relatively low temperature condition of about room temperature to about 150 ° C., and is therefore most suitable for lowering the temperature of the MIM element manufacturing process. Therefore, there is a feature that a degree of freedom in selecting a substrate material to be used is widened and a uniform film can be obtained over a large area because the substrate temperature can be easily controlled. Further, as shown in Table 1, the structure and physical properties of the hard carbon film can be controlled in a wide range, and therefore, there is an advantage that device characteristics can be freely designed. Further, the relative dielectric constant of the film is 2 to 6, which is Ta which has been used for the conventional MIM element.
_Since it is smaller than ₂ O ₅ , Al ₂ O ₃ , and SiNx, when manufacturing an element having the same electric capacity, the element size can be large, so that fine processing is not so required and the yield is improved (driving From the relation of conditions, the capacitance ratio between the LCD and the MIM element needs to be about C (LCD) / C (MIM) = 10: 1). Further, since the element steepness β∝1 / √ε · √d, if the relative dielectric constant ε is small, the steepness increases, and the ratio between the on current Ion and the off current Ioff can be increased. For this reason, the LCD can be driven at a lower duty ratio, and a high-density LCD can be realized. Further, since the hardness of the film is high, the damage due to the rubbing step at the time of enclosing the liquid crystal material is small, and the yield is also improved from this point. In view of the above points, the use of a hard carbon film makes it possible to realize a low-cost, gradation (color) and high-density LCD.

Further, in addition to carbon atoms and hydrogen atoms, the hard carbon film is composed of a Group III element, a Group IV element,
The group V element, alkali metal element, alkaline earth metal element, nitrogen atom, oxygen element, chalcogen element or halogen atom may be included as a constituent element. As one of the constituent elements, those in which Group III element of the periodic table, Group V element, alkali metal element, alkaline earth metal element, nitrogen atom or oxygen atom are introduced are those in which the thickness of the hard carbon film is non-doped The thickness can be increased by about 2 to 3 times as compared with the above, and thereby, the generation of pinholes at the time of manufacturing the device can be prevented, and the mechanical strength of the device can be remarkably improved. Further, in the case of a nitrogen atom or an oxygen atom, the same effect as in the case of a group IV element of the periodic table as described below is obtained. In the same way, the elements incorporating a Group IV element of the periodic table, a chalcogen-based element or a halogen element significantly improve the stability of the hard carbon film and also improve the hardness of the film. Can be produced. These effects are obtained because the group IV element and the chalcogen-based element reduce the active double bond existing in the hard carbon film. In the case of the halogen element, 1) abstraction with respect to hydrogen The reaction promotes the decomposition of the source gas to reduce dangling bonds in the film. 2) During the film formation process, the halogen element X extracts hydrogen in the C—H bond and replaces it.
This is because they enter the film as CX bonds, and the bond energy increases (the bond energy between CH and CX is larger between CX). In order to make these elements the constituent elements of the film, in addition to hydrocarbon gas and hydrogen as the raw material gas, and in the film as a dopant in the periodic table III as a dopant,
In order to contain group element, group IV element, group V element, alkali metal element, alkaline earth metal element, nitrogen atom, oxygen atom, chalcogen element or halogen element, include these elements or atoms Compound (or molecule) (hereinafter referred to as
These are sometimes referred to as “other compounds”.

The compound containing a Group III element of the periodic table includes, for example, B (OC ₂ H ₅ ) ₃ , B ₂ H ₆ , BC
_{l 3, BBr 3, BF 3} , Al (O-i-C 3 H 7) 3, (C
_{H 3) 3 Al, (C} 2 H 5) 3 Al, (i-C 4 H 9) 3 Al,
_{AlCl 3, Ga (O-i} -C 3 H 7) 3, (CH 3) 3 G
_{a, (C 2 H 5)} 3 Ga, GaCl 3, GaBr 3, (O-
_{i-C 3 H 7) 3} In, there is a (C ₂ H _{5) 3} In like. As the compound containing a Group IV element of the periodic table, for example, Si
₂ H ₆ , (C ₂ H ₅ ) ₃ SiH, SiF ₄ , SiH ₃ Cl, S
iCl ₄ , Si (OCH ₃ ) ₄ , Si (OC ₂ H ₅ ) ₄ , Si
(OC ₃ H ₇ ) ₄ , GeCl ₄ , GeH ₄ , Ge (OC
_{2 H 5) 4, Ge (} C 2 H 5) 4, (CH 3) 4 Sn, (C
₂ H _{5) 4} Sn, there is SnCl ₄ and the like. Examples of the compound containing a Group V element of the periodic table include PH ₃ , PF ₃ , PF ₅ ,
PCl ₂ F ₃ , PCl ₃ , PCl ₂ F, PBr ₃ , PO (O
CH ₃ ) ₃ , P (C ₂ H ₅ ) ₃ , POCl ₃ , AsH ₃ , As
Cl ₃ , AsBr ₃ , AsF ₃ , AsF ₅ , AsCl ₃ , S
bH ₃ , SbF ₃ , SbCl ₃ , Sb (OC ₂ H ₅ ) _{3 and the} like. As the compound containing an alkali metal atom, for example, L
_{iO-i-C 3 H 7} , NaO-i-C 3 H 7, KO-i-C
There are ₃ H ₇ and the like. Examples of the compound containing an alkaline earth metal atom include Ca (OC ₂ H ₅ ) ₃ , Mg (OC ₂ H ₅ ) ₂ ,
(C ₂ H ₅ ) ₂ Mg and the like. Examples of the compound containing a nitrogen atom include nitrogen gas, inorganic compounds such as ammonia, organic compounds having a functional group such as an amino group and a cyano group, and heterocycles containing nitrogen. Examples of the compound containing an oxygen atom include oxygen gas, ozone, water (steam), hydrogen peroxide, carbon monoxide, carbon dioxide, carbon suboxide, nitric oxide, nitrogen dioxide, nitrous oxide, and nitrous oxide. Functional groups or bonds such as inorganic compounds such as nitric oxide, hydroxyl groups, aldehyde groups, acyl groups, ketone groups, nitro groups, nitroso groups, sulfone groups, ether bonds, ester bonds, peptide bonds, and heterocycles containing oxygen. Organic compounds, and metal alkoxides. As a compound containing a chalcogen element, for example, H ₂ S, (CH ₃ ) (CH
₂ ) ₄ S (CH ₂ ) ₄ CH ₃ , CH ₂ = CHCH ₂ SCH ₂ CH
_{= CH 2, C 2 H 5} SC 2 H 5, C 2 H 5 SCH 3, thiophene, H ₂ Se, there are _{(C 2 H 5) 2 Se} , H 2 Te. Examples of the compound containing a halogen element include fluorine, chlorine, bromine, iodine, hydrogen fluoride, carbon fluoride, chlorine fluoride, bromine fluoride, iodine fluoride, hydrogen chloride, bromine chloride, iodine chloride, and hydrogen bromide. , Iodine bromide, inorganic compounds such as hydrogen iodide, alkyl halides, aryl halides, halogenated styrenes,
Organic compounds such as halogenated polymethylene and haloform are used.

The hard carbon film suitable for the liquid crystal driving MIM element has an advantageous thickness of 100 to 8000 ° and a specific resistance of 10 ⁶ to 10 ¹³ Ω · cm in terms of driving conditions. In consideration of a margin between a driving voltage and a withstand voltage (dielectric breakdown voltage), the film thickness is desirably 200 ° or more, and color unevenness caused by a step (cell gap difference) between a pixel portion and a thin-film two-terminal device portion. In order not to cause a problem in practice, it is desirable that the film thickness is 6000 ° or less, so that the film thickness of the hard carbon film is 200 to 6000 ° and the specific resistance is 5 × 10 ⁶ to 10 ¹³ Ω · cm. Is more preferable. The number of defects in the element due to pinholes in the hard carbon film increases as the film thickness decreases, and becomes particularly remarkable below 300 ° (the defect rate exceeds 1%), and the in-plane distribution of the film thickness is uniform. Properties (and, consequently, uniformity of element characteristics) cannot be secured (the accuracy of film thickness control is limited to about 30 °,
Since the variation of the film thickness exceeds 10%), the film thickness is 3
More preferably, it is not less than 00 °. Further, in order to make it difficult for the hard carbon film to peel off due to stress and to drive at a lower duty ratio (preferably 1/1000 or less), the film thickness is more preferably 4000 ° or less. Taking these into consideration, the thickness of the hard carbon film is 300 to 4000 ° and the specific resistivity is 10 ⁷
More preferably, it is 10 to 10 ¹¹ Ω · cm.

[0017]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described.
It is not limited to them. Example 1 As shown in FIG. 1, a 100 μ thick amorphous polyarylate
6000 on both sides of film 1 by sputtering
ＳｉＯ thick SiO_TwoLayers (2a, 2b) were formed. Amorphous
Glassy transition temperature of 215 ° C
Use those with a transmittance of 90% or more at a length of 400 to 850 nm
Was. The SiO_TwoThe fabrication conditions are that the substrate temperature is 50 ° C or less.
The film formation was performed at a deposition rate of 300 ° / min. This SiO_Two
The film was found to be amorphous by X-ray diffraction and electron diffraction.
won. Next, SiO_TwoITO on top by sputtering
After deposition to a thickness of about 1000 mm, patterning and pixel electrode
Was formed. Next, the MIM element is provided as follows.
Was. First, after depositing Al to a thickness of about 1000
The lower electrode 7 is formed by patterning, and an insulating layer
As No. 2, a hard carbon film was formed by plasma CVD for about 10
After being deposited to a thickness of about
Turned. The conditions for forming the hard carbon film at this time are as follows:
It is on the street. Pressure: 0.035 Torr CH_FourFlow rate: 10 SCCM RF power: 0.2 w / cm^Two  Further, Ni is deposited thereon by an EB evaporation method to a thickness of about 1000 mm.
After patterning, an upper electrode 6 was formed by patterning.

Example 2 As shown in FIG. 1, a 100 μm thick amorphous polyether
On both sides of the film 1 by sputtering
5000mm thick Si_ThreeN_FourLayers (2a, 2b) were formed.
Amorphous polyether sulfone film has glass transition point
223 ° C, transmittance of 84% or less at a wavelength of 400 to 850 nm
The above was used. Next, SiO_TwoSputter ITO on top
Deposit about 1000mm thick by ring method
To form a pixel electrode. Next, the MIM element is
Provided. First, about 1000 mm thick Al
After depositing, a lower electrode 7 is formed by patterning,
Next, a hard carbon film is formed as an insulating layer 2 by a plasma CVD method.
After depositing more than 1000mm thick, dry etch
Patterning. At this time, the strip of hard carbon film
The matter is as follows. Pressure: 0.035 Torr CH_FourFlow rate: 10 SCCM RF power: 0.2 w / cm^Two  Further, Ni is deposited thereon by an EB evaporation method to a thickness of about 1000 mm.
After patterning, an upper electrode 6 was formed by patterning. Implementation
Using the MIM elements manufactured in Examples 1 and 2, a liquid crystal display
When the device was manufactured, good display characteristics were obtained.

Comparative Example 1 As in Examples 1 and 2, uniaxially stretched
Sputtering on both sides of ethylene terephthalate film
6000mm thick SiO_TwoLayer (2a, 2b)
Was prepared. Used uniaxially stretched polyethylene tere turret
As a result of X-ray diffraction, the film had crystallinity. Ma
At a glass transition point of 80 ° C. and a wavelength of 400 to 850 nm.
The transmittance was 83 ° or more. Next, SiO_TwoITO on top
After depositing to a thickness of about 1000mm by sputtering,
To form pixel electrodes. Next, set the MIM element.
First, about 1000 mm thick Al is deposited by evaporation.
After patterning, a lower electrode 7 is formed, and
Next, a hard carbon film is formed as an insulating layer 2 by a plasma CVD method.
After depositing more than 1000mm thick, dry etch
Patterning. At this time, the strip of hard carbon film
The matter is as follows. Pressure: 0.035 Torr CH_FourFlow rate: 10 SCCM RF power: 0.2 w / cm^Two  Further, Ni is deposited thereon by an EB evaporation method to a thickness of about 1000 mm.
After deposition on the surface, patterning was attempted.
Pattern shift occurred. Even if the exposure area is reduced, Ni
The pattern could not be formed. Also, how to stretch
Observation of film peeling corresponding to the direction and deformation of the pattern due to heat
Was done.

[0020]

Since the present invention is configured as described above, the thin-film laminated device of the present invention is free from substrate deformation, curl, and pattern shift, and can achieve low cost and light weight. When a thin-film laminated device is an MIM-type element using a hard carbon film as an insulating layer, the hard carbon film is manufactured by a gas phase synthesis method such as a plasma CVD method. 2) Hardness and a thick film make it hard to be damaged mechanically, and can be expected to reduce pinholes by thickening. 3) At low temperature around room temperature 4) Suitable for thin film devices because of excellent uniformity of film thickness and film quality. 5) Highly fine because of low dielectric constant. processing No operation is required, therefore, it is advantageous to increase the area of the element. Further, since the dielectric constant is low, the steepness of the element is high and the Ion / Ioff ratio can be obtained, so that driving at a low duty ratio is possible. It has features and is therefore particularly suitable as a highly reliable switching element for a liquid crystal display, and is extremely useful in industry.

[Brief description of the drawings]

FIG. 1 is a sectional view showing a structure of a thin film device of the present invention.

FIG. 2 shows an MIM constituted by the thin film device of the present invention.
FIG. 4 is an explanatory diagram of a main part of an element.

FIG. 3 is a partial sectional perspective view of a liquid crystal display device incorporating the thin film device of the present invention.

FIG. 4A is an IV characteristic curve of the MIM element, and b is lnI.
4 is a graph showing a -√v characteristic curve.

FIG. 5 shows a Gaussian distribution by a 1R spectrum of a hard carbon film used for an insulating layer of the MIM element of the present invention.

FIG. 6 is a spectrum diagram showing an analysis result obtained by spectroscopy of a hard carbon film used for an insulating layer of the MIM element of the present invention by an IR absorption method.

FIG. 7 is a spectrum diagram showing an analysis result obtained by analyzing a hard carbon film used for an insulating layer of the MIM element of the present invention by a Raman spectrum method.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Plastic substrate 1 'Plastic substrate 2 Hard carbon film 2a Inorganic substance 2b Inorganic substance 3 Liquid crystal 4 Pixel electrode 4' Common electrode 5 Active element (MIM element) 6 Second conductor (bus line) (upper electrode) 7 First conductor ( Lower electrode) 8 alignment film 9 gap material

Continued on the front page (72) Inventor Masayoshi Takahashi 1-3-6 Nakamagome, Ota-ku, Tokyo Inside Ricoh Company (72) Inventor Yuji Kimura 1-3-6 Nakamagome, Ota-ku, Tokyo Co., Ltd. Inside Ricoh (72) Inventor Kenji Kameyama 1-3-6 Nakamagome, Ota-ku, Tokyo Inside Ricoh Company (72) Inventor Makoto Tanabe 1-3-6 Nakamagome, Ota-ku, Tokyo Inside Ricoh Company (56) reference Patent flat 2-259729 (JP, a) JP Akira 60-7420 (JP, a) JP flat 4-143724 (JP, a) (58 ) investigated the field (Int.Cl. ⁶ , DB name) H01L 27/12 G02F 1/133 550 G02F 1/136 510 H01L 29/786 H01L 49/00

Claims (2)

(57) [Claims] 1. A substrate and a thin-film laminated device formed on the substrate, wherein the substrate has a thickness of 5,000 to 10 on both sides.
000 ° SiOx (1 ≦ x ≦ 2), Si: O: N, S
i: O: H, Si: N: H, Si: O: N: H, Si ₃
N ₄ , TiO ₂ , ZnS, ZnO, Al ₂ O ₃ , Al
_{N, MgO, GeO, ZrO 2} , Nb 2 O 5, SiC and _Ta 2 _{O 5} has an inorganic material layer selected from the group consisting of and with the substrate, wherein the substrate is amorphous plastics Thin film stacking device. 2. The plastic substrate has a transmittance of 80% or more at a wavelength of 400 to 850 nm.
The thin-film laminated device with a substrate according to 1.