JPH04253385A - Thin film laminated device - Google Patents

Abstract

PURPOSE:To obtain a thin film laminated device having high reliability without film peeling, curl, etc., with a light weight and a low cost by forming a board of plastic in which thin amorphous films made of inorganic substance are formed on both side surfaces. CONSTITUTION:A plastic film 1 made of polyethylene terephthalate, polyacrylate, polyethersulfone, polycarbonate, polymethylmethacrylate, polyimide, etc., is formed at both sides 1a, 1b with inorganic substance such as SiOX (1<=X<=2), Si:O:N, Si:O:H, Si:N:H, Si:O:N:H, SiXNY (Y=1-X), TiO2, ZnS, ZnO, Al2O3, AlN, MgO, GeO, ZrO2, Nb2O5, SiC, Ta2O5, etc., desirably 1000-10000Angstrom thick by a sputtering method, etc., a substrate temperature is set, to provide amorphous substance, to 150 deg.C or lower, and the film is manufactured by a sputtering method.

Description

[Detailed description of the invention]

0001

TECHNICAL FIELD The present invention relates to a thin film laminated device, and more particularly to a switching element that can be suitably used in flat panel displays for office automation equipment, TVs, and the like.

0002

2. Description of the Related Art There is a strong demand for the use of large-area liquid crystal panels in office automation equipment terminals and liquid crystal TVs, and for this reason, in the active matrix system, a switch is provided for each pixel to maintain the voltage. Further, in recent years, there have been active efforts to reduce the weight and cost of liquid crystal panels, and the use of plastic for the substrates of switching elements is being considered. However, when a thin film laminated switching element is formed on plastic, there are problems such as deformation and curling of the plastic substrate, and film peeling. Additionally, when manufacturing thin film laminated switching elements, there is a photolithography process in which plastic is immersed in a solution of acid, alkali, water, etc., and acid, alkali, water, etc. remain in the plastic, which can cause element deterioration. became. When finely patterning a thin film stacked device, expansion and contraction of the substrate causes pattern shift, making it difficult to expose a large area at once. Furthermore, the anisotropy of substrate expansion and contraction made pattern formation even more difficult. In manufacturing a liquid crystal display device using a plastic film substrate, it is necessary to use an alignment method unique to plastics during alignment treatment. However, SiO2
Japanese Patent Publication No. 1-47769 discloses that by forming a layer on one side of a plastic film, alignment treatment can be performed in the same manner as for glass substrates. However, when SiO2 is coated on a plastic film and a thin film laminated device is fabricated on it, cracks are often observed in the SiO2 during the manufacturing process that involves heat, resulting in insufficient reliability of the thin film laminated device. I took it as a thing.

0003

[Objective] The present invention aims to solve the above-mentioned conventional problems and provide a thin film laminated device that is lightweight, low cost, free from peeling, curling, etc., and has good reliability.

0004

[Structure] In order to achieve the above object, the present inventors have considered fabricating switching elements on lightweight and inexpensive plastic, and as a result of repeated research, they have found that the deformation of the plastic substrate during the element fabrication process is Curl has proven to be the biggest problem with plastic films. In addition, we discovered that the causes of plastic deformation and plastic film curling are internal stress in laminated thin films, thermal expansion and contraction of plastic, and swelling due to acids, alkalis, and water. It has become clear that it is effective to use a plastic substrate formed on both sides, and the present invention has been completed. That is, the present invention is characterized in that, in a substrate and a thin film laminated device formed on the substrate, the substrate is made of plastic with amorphous thin films made of an inorganic substance formed on both surfaces thereof.

[0005] Amorphous thin films made of inorganic substances have a wavelength of 400 nm.
It is preferable that the transmittance is 75% or more in the range of 850 nm to 850 nm. Inorganic substances include SiO2, Si3N4, Si:N:
O, Si:O:H, Si:N:H, Si:O:N:H,
Preferably, it is selected from the group consisting of AlN. Further, as a thin film laminated device, an MIM type element having a hard carbon film as an insulating layer can exhibit the features of the present invention extremely effectively. SiO2 on plastic substrate
The formation of inorganic thin films such as these is important for solving problems such as peeling of thin film laminated devices fabricated thereon. If the thin film is formed only on one side of the plastic substrate (film), curling will occur depending on the internal stress of the inorganic thin film, resulting in problems such as handling. Furthermore, it has been found that when the inorganic material thin film is crystalline, moisture etc. inherent in the plastic substrate reach the bottom of the thin film stacked device through the crystal grain boundaries, causing deterioration of the device. Furthermore, cracks occurred in the inorganic material thin film with crystal grain boundaries as nuclei during the thermal step in the thin film laminated device fabrication process. Furthermore, it has been found that when fine-fabricating a thin film stacked device, anisotropy of expansion and contraction of the substrate occurs due to the anisotropy of thermal expansion of the inorganic material, making pattern formation difficult. In order to avoid these problems, it is important to form amorphous thin films made of inorganic substances on both sides of the plastic substrate (film). When the thin film laminated device of the present invention is used in a liquid crystal display driving element, in order to ensure display contrast, it is preferable that the inorganic substance has a transmittance of 75% or more at a wavelength of 400 to 850 nm. In order to produce the thin film laminated device of the present invention, first, SiOx (1≦x≦2) is applied to both sides of a plastic or plastic film such as polyethylene terephthalate, polyarylate, polyethersulfone, polycarbonate, polyethylene, polymethyl methacrylate, or polyimide. ,Si
:O:N, Si:O:H, Si:N:H, Si:O:N
:H, SixNy (y=1-x), TiO2, ZnS,
ZnO, Al2O3, AlN, MgO, GeO, ZrO
2. Inorganic materials such as Nb2O5, SiC, and Ta2O5 are deposited by sputtering, vapor deposition, plasma CVD, etc.
It is formed to a thickness of ~15,000 Å, preferably 1,000 to 10,000 Å. In order to make these inorganic substances amorphous, it is preferable to lower the substrate temperature to 200° C. or lower, preferably 150° C. or lower, and to manufacture by sputtering or plasma CVD. The formed thin film does not necessarily need to have the same inorganic substance on both sides, nor does it need to have the same film thickness. Particularly preferable inorganic substances include SiO2, Si3N4, and Si:N, which have a large passivation effect.
O, Si:O:H, Si:N:H, Si:O:N:H,
Examples include AlN. The thickness of the plastic is 50 μm ~
2 mm is used, but it is less than 500 μm, especially 30 μm.
It is preferably 0 μm or less. Furthermore, a thin film laminated device is formed on the plastic coated on both sides with an inorganic substance. As a thin film stacked device, an MIM type element with a metal-insulator-metal layer structure, an MSI element (Metal-Semi-I
SIS devices having a semiconductor-insulator-semiconductor layer structure, and MIMIM devices having a metal-insulator-metal-insulator-metal structure described in Japanese Patent Application Laid-open No. 7577/1983. Among these, an MIM type element using a hard carbon film as an insulator is advantageous. When a hard carbon film is used as an insulating layer, the plastic substrate (film) will curl significantly, so this can be countered by forming an inorganic film on both sides of the substrate to increase the rigidity of the substrate.

[0006] Next, a method for manufacturing the above-mentioned element will be explained in detail. First, coat both sides with the above-mentioned inorganic substance (2a, 2b
) A transparent electrode material for a pixel electrode is deposited on the plastic substrate 1 by a method such as vapor deposition or sputtering, and patterned into a predetermined pattern to form a pixel electrode 4. Next, a conductor thin film for the lower electrode is formed by a method such as vapor deposition or sputtering, and patterned into a predetermined pattern by wet or dry etching to form the first conductor 7 that will become the lower electrode,
A hard carbon film 2 is coated thereon by a plasma CVD method, an ion beam method, etc., and then patterned into a predetermined pattern by dry etching, wet etching, or a lift-off method using a resist to form an insulating film. A conductive thin film for the bus line is coated by a method such as sputtering, and patterned into a predetermined pattern to form the second conductor 6 that will become the bus line.Finally, unnecessary portions of the lower electrode are removed to expose the transparent electrode pattern. This is used as the pixel electrode 4. In this case, the configuration of the MIM element is not limited to this, but after the MIM element is fabricated, a transparent electrode is provided on the top layer, a transparent electrode also serves as an upper or lower electrode, a side surface of the lower electrode, etc. Various modifications are possible, such as one in which an MIM element is formed on the top. Here the bottom electrode,
The thickness of the upper electrode and transparent electrode is usually several hundred to several thousand Å each.
, in the range of several hundred to several thousand Å, and in the range of several hundred to several thousand Å. The thickness of the hard carbon film is 100 to 8000 Å, preferably 200 to 8000 Å.
The thickness is preferably 6000 Å, more preferably 300 to 4000 Å. Furthermore, in the case of plastic substrates, it has been extremely difficult to fabricate active matrix devices using active elements due to their heat resistance. However, a hard carbon film can be produced at a substrate temperature of about room temperature, and can also be produced on a plastic substrate, making it a very effective means for improving image quality.

Next, the material of the MIM element used in the present invention will be explained in more detail. The material of the first conductor 7 serving as the lower electrode includes Al, Ta, Cr, W, Mo, and Pt.
, Ni, Ti, Cu, Au, ITO, ZnO: Al, I
Various conductors such as n2O3 and SnO2 are used. Next, the material of the second conductor 6 which becomes the bus line is Al, C.
r, Ni, Mo, Pt, Ag, Ti, Cu, Au, W,
Various conductors can be used, such as Ta, ITO, ZnO:Al, In2O3, SnO2, etc., but Ni, Pt, and Ag are preferred because of their particularly excellent stability and reliability of IV characteristics. In the MIM device using the hard carbon film 2 as an insulating film, the symmetry does not change even if the type of electrode is changed, and lnI∝
From the relationship √v, it can be seen that Poole-Frenkel type conduction is occurring. Also, from this fact, in the case of this type of MIM element,
It can be seen that the upper electrode and lower electrode may be combined in any way. However, the device characteristics (IV characteristics) deteriorate and change depending on the adhesion between the hard carbon film and the electrode and the state of the interface. Considering these, it was found that Ni, Pt, and Ag are good. The current-voltage characteristics of the MIM element of the present invention are shown in FIG. 4, and are approximately expressed by the conduction equation shown below.

[0008]

[Math 1]

I: Current V: Applied voltage κ: Conductivity coefficient
β: Poole-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: Ambient temperature ε
1: Dielectric constant of hard carbon ε2: Vacuum dielectric constant

Next, a method for manufacturing a liquid crystal display device will be described with reference to FIG. First, a transparent conductor for the common electrode 4', such as ITO, ZnO:Al, ZnO:Si, Sn, is placed on the insulating substrate 1'.
O2, In2O3, etc. are sputtered, vapor-deposited, etc. to a thickness of several hundred Å.
The common electrode 4' is deposited to a thickness of several μm and patterned into stripes. Substrate 1 provided with this common electrode 4'
', an alignment material 8 such as polyimide is applied to the surface of each substrate 1 on which MIM elements are provided in a matrix, a rubbing treatment is performed, a sealing material is applied, a gap material 9 is inserted to make the gap constant, The liquid crystal 3 is sealed to form a liquid crystal display device. In this way, a liquid crystal display device is obtained.

The hard carbon film used in the MIM element of the device of the present invention will be explained 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 have to be a gas phase at normal temperature and pressure; they can be used in either a liquid or solid phase as long as they can be vaporized through melting, evaporation, sublimation, etc. by heating or reduced pressure. be. Regarding hydrocarbon gas as raw material gas, for example, CH4, C2H6, C3H8
, C4H10, etc., olefinic hydrocarbons such as C2H4, diolefinic hydrocarbons, and even aromatic hydrocarbons. Furthermore, other than hydrocarbons, compounds containing at least the carbon element can be used, such as alcohols, ketones, ethers, esters, CO, and CO2. In the method of forming a hard carbon film from a raw material gas in the present invention, the film-forming active species is
It is preferable to use a plasma state generated by a plasma method using direct current, low frequency, high frequency, microwave, etc., but for the purpose of increasing the area, improving uniformity, and forming a film at a low temperature, A method using a magnetic field effect is more preferable. Active species can also be formed by thermal decomposition at high temperatures. In addition, it may be formed through an ion state generated by an ionization vapor deposition method, an ion beam vapor deposition method, etc., or a vacuum vapor deposition method,
Alternatively, it may be formed from neutral particles produced by a sputtering method or the like, or may be formed from a combination of these.

An example of the deposition conditions for the hard carbon film produced in this manner is as follows in the case of the plasma CVD method. RF output: 0.1 to 50 W/cm2 Pressure: 1/103 to 10 Torr Deposition temperature: Room temperature to 350°C Due to this plasma state, the raw material gas is decomposed into radicals and ions and reacts, thereby forming carbon atoms C on the substrate.
A hard carbon film containing at least one of amorphous (amorphous) and microcrystalline (crystal size is several tens of angstroms to several μm) is deposited. Further, Table 1 shows various properties of the hard carbon film.

[0013]

[Table 1]

Note) Measuring method: Specific resistance (ρ): Obtained from the IV characteristics using a coplanar cell. Optical bandgap (Egopt):
Obtain the absorption coefficient (α) from the spectral characteristics and determine it from the relationship shown in Equation 2.

[0015]

[Equation 2] Amount of hydrogen in the film [C(H)]: 29 from the infrared absorption spectrum
It is determined by integrating the peak near 00/cm and multiplying it by the absorption cross section A. That is, [C(H)]=A・∫α(v)/v・dvSP3/SP
2 ratio: The infrared absorption spectrum is decomposed into Gaussian functions assigned to SP3 and SP2, respectively, and determined from the area ratio. Vickers hardness (H): Based on a micro Vickers meter. Refractive index (n): By ellipsometer. Defect density: Based on ESR.

As a result of analysis by Raman spectroscopy and IR absorption method, the hard carbon film thus formed shows that the carbon atoms have SP3 hybrid orbitals and SP2 hybrid orbitals, as shown in FIGS. 6 and 7, respectively.
It has become clear that there are interatomic bonds that form a hybrid orbital. The ratio of SP3 bonds to SP2 bonds can be approximately estimated by peak-separating the IR spectrum. 2800-3150/cm for IR spectrum
Although the spectra of many modes overlap and are measured,
The attribution of peaks corresponding to each wave number is clear, and if we perform peak separation using a Gaussian distribution as shown in Figure 5, calculate the area of each peak, and find the ratio, we can obtain SP.
3/SP2 can be known. Moreover, according to X-ray and electron diffraction analysis, it has been found that it is in an amorphous state (a-C:H) and/or an amorphous state containing microcrystalline grains of about 50 Å to several μm. In the case of the plasma CVD method, which is generally suitable for mass production, the lower the RF output, the higher the specific resistance and hardness of the film, and the lower the pressure, the longer the life of active species, so lowering the substrate temperature and increasing the The area can be made uniform, and the specific resistance and hardness tend to increase. Furthermore, since the plasma density decreases at low pressures, methods using magnetic field confinement effects are particularly effective in increasing resistivity. Furthermore, this method has the characteristic that it can form a hard carbon film of good quality even under relatively low temperature conditions of about room temperature to 150° C., so it is optimal for lowering the temperature of the MIM element manufacturing process. Therefore, the degree of freedom in selecting the substrate material to be used is increased, and the substrate temperature can be easily controlled, so that a uniform film can be obtained over a large area. Furthermore, as shown in Table 1, the structure and physical properties of the hard carbon film can be controlled over a wide range, so there is an advantage that device characteristics can be designed freely. Furthermore, the dielectric constant of the film is 2 to 6, which is Ta2O, which is used in conventional MIM devices.
5.Since it is smaller than Al2O3 and SiNx, when making an element with the same capacitance, the element size only needs to be larger, so it does not require much fine processing and the yield improves (because of the driving conditions, LCD The capacitance ratio of C(LCD)/C(MIM) = approximately 10:1 is required between C(LCD) and MIM element. Furthermore, since the element steepness β∝1/√ε·√d, the smaller the dielectric constant ε, the greater the steepness, and the ratio between the on-current Ion and the off-current Ioff can be increased. Therefore, it becomes possible to drive the LCD at a lower duty ratio, and a high-density LCD can be realized. Furthermore, since the film has high hardness, there is less damage caused by the rubbing process during encapsulation of the liquid crystal material, which also improves the yield. Considering the above points, by using a hard carbon film, a low-cost, gradation (color), and high-density LCD can be realized. In addition to carbon atoms and hydrogen atoms, this hard carbon film
It may contain a Group III element, a Group IV element, a Group V element, an alkali metal element, an alkaline earth metal element, a nitrogen atom, an oxygen element, a chalcogen element, or a halogen atom as a constituent element. If a group III element of the periodic table, a group V element, an alkali metal element, an alkaline earth metal element, nitrogen atom, or oxygen atom is introduced as one of the constituent elements, the thickness of the hard carbon film is non-doped. It can be made about 2 to 3 times thicker than that of 100%, and this can prevent the occurrence of pinholes during device fabrication and dramatically improve the mechanical strength of the device. 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 can be obtained. Similarly, devices incorporating Group IV elements of the periodic table, chalcogen elements, or halogen elements dramatically improve the stability of the hard carbon film and improve the hardness of the film, resulting in highly reliable elements. can be made. These effects can be obtained because Group IV elements and chalcogen elements reduce the active double bonds present in the hard carbon film, and in the case of halogen elements, 1) abstraction for hydrogen The reaction promotes the decomposition of the raw material gas and reduces dangling bonds in the film, and 2) during the film formation process, the halogen element X pulls out hydrogen in the C-H bond and replaces it, forming a C-X bond. enters the membrane and increases the binding energy (C-
This is because the bond energy between H and between C-X is larger for C-X. In order to use these elements as constituent elements of the film, in addition to hydrocarbon gas and hydrogen as raw material gases, group III elements of the periodic table,
In order to contain Group IV elements, Group V elements, alkali metal elements, alkaline earth metal elements, nitrogen atoms, oxygen atoms, chalcogen elements, or halogen elements, compounds containing these elements or atoms (or molecules) (hereinafter these may also be referred to as "other compounds") gases are used. Examples of compounds containing Group III elements of the periodic table include B(OC2H5)3, B2H6, BCl3,
BBr3, BF3, Al(O-i-C3H7)3, (C
H3)3Al, (C2H5)3Al, (i-C4H9)
3Al, AlCl3, Ga(O-i-C3H7)3, (
CH3)3Ga, (C2H5)3Ga, GaCl3,G
aBr3, (O-i-C3H7)3In, (C2H5)
There are 3In etc. Examples of compounds containing Group IV elements of the periodic table include S
i2H6, (C2H5)3SiH, SiF4, SiH2
Cl2, SiCl4, Si(OCH3)4, Si(OC
2H5)4, Si(OC3H7)4, GeCl4, Ge
H4,Ge(OC2H5)4,Ge(C2H5)4,(
There are CH3)4Sn, (C2H5)4Sn, SnCl4, etc. Examples of compounds containing Group V elements of the periodic table include PH
3, PF3, PF5, PCl2F3, PCl3, PCl
2F, PBr3, PO(OCH3)3, P(C2H5)
3, POCl3, AsH3, AsCl3, AsBr3,
AsF3, AsF5, AsCl3, SbH3, SbF3
, SbCl3, Sb(OC2H5)3, etc. As a compound containing an alkali metal atom, for example, LiO
-i-C3H7, NaO-i-C3H7, KO-i-C
There are 3H7 etc. Examples of compounds containing alkaline earth metal atoms include C
a(OC2H5)3, Mg(OC2H5)2, (C2H
5) There are 2Mg, etc. Examples of compounds containing nitrogen atoms include nitrogen gas, inorganic compounds such as ammonia, organic compounds having functional groups such as amino groups and cyano groups, and nitrogen-containing heterocycles. Examples of compounds containing oxygen atoms include oxygen gas, ozone, water (steam), hydrogen peroxide, carbon monoxide, carbon dioxide, suboxide, nitrogen monoxide, nitrogen dioxide, dinitrogen trioxide, and dinitrogen pentoxide. , inorganic compounds such as nitrogen trioxide, hydroxyl groups, aldehyde groups, acyl groups, ketone groups, nitro groups, nitroso groups, sulfone groups, ether bonds, ester bonds, peptide bonds, and functional groups or bonds such as heterocycles containing oxygen. Further, examples thereof include organic compounds having a metal alkoxide, metal alkoxides, and the like. Examples of compounds containing chalcogen elements include H2S
, (CH3)(CH2)4S(CH2)4CH3,CH
2=CHCH2SCH2CH=CH2,C2H5SC2
H5, C2H5SCH3, thiophene, H2Se, (C
2H5) 2Se, H2Te, etc. Compounds containing halogen elements include, for example, fluorine,
Inorganic compounds such as chlorine, bromine, iodine, hydrogen fluoride, carbon fluoride, chlorine fluoride, bromine fluoride, iodine fluoride, hydrogen chloride, bromine chloride, iodine chloride, hydrogen bromide, iodine bromide, hydrogen iodide, etc. Organic compounds such as halogenated alkyl, halogenated aryl, halogenated styrene, halogenated polymethylene, and haloform are used. It is advantageous for a hard carbon film suitable as a liquid crystal driving MIM element to have a film thickness in a range of 100 to 8000 Å and a specific resistance in a range of 10 6 to 10 13 Ω·cm in view of driving conditions. In addition, considering the margin between drive voltage and withstand voltage (dielectric breakdown voltage), it is desirable that the film thickness be 200 Å or more, and color unevenness due to the step difference (cell gap difference) between the pixel part and the thin film two-terminal element part should be avoided. In order to prevent this from becoming a practical problem, it is desirable that the film thickness be 6000 Å or less, so the thickness of the hard carbon film should be 200 to 6000 Å.
It is more preferable that the specific resistance is 5×10 6 to 10 13 Ω·cm. The number of device defects due to pinholes in hard carbon films increases as the film thickness decreases, and becomes especially noticeable below 300 Å (defect rate exceeds 1%), and the uniformity of the in-plane distribution of film thickness (The accuracy of film thickness control is limited to about 30 Å, and the variation in film thickness exceeds 10%).
More preferably, the film thickness is 300 Å or more. Also,
In order to prevent the hard carbon film from peeling off due to stress, the duty ratio should be lower (preferably 1/100).
0 or less), the film thickness is more desirably 4000 Å or less. Taking these into consideration,
The thickness of the hard carbon film is 300 to 4000 Å, and the specific resistivity is 1.
More preferably, it is 07 to 1011 Ω·cm.

[0017]

EXAMPLES Examples of the present invention will be described, but the present invention is not limited thereto. Example 1 As shown in FIG. 1, SiO2 layers (2a, 2b) with a thickness of 6000 Å were formed on both sides of a polyarylate film 1 with a thickness of 100 μm by a sputtering method at a substrate temperature of 50° C. X-ray diffraction revealed that the SiO2 film was amorphous. Further, it exhibited a transmittance of 80% or more in the wavelength range of 400 to 850 nm. Next, ITO was deposited on SiO2 to a thickness of about 1000 Å by sputtering, and then patterned to form a pixel electrode. Next, an MIM element was provided as follows. First, Al was deposited to a thickness of about 1000 Å by vapor deposition and patterned to form the lower electrode 7. On top of that, a hard carbon film was deposited to a thickness of about 1000 Å by plasma CVD as an insulating layer 2, and then dried. Patterned by etching. The conditions for forming the hard carbon film at this time are as follows. Pressure: 0.035TorrCH4 Flow rate:
10 SCCM RF power: 0.2 W/cm2 Furthermore, Ni is deposited on this by approximately 1000 Å by EB evaporation method.
The upper electrode 6 was formed by depositing it thickly and patterning it.

Example 2 As shown in FIG. 1, Si3N4 layers 2a and 2b with a thickness of 5000 Å were formed on both sides of a 250 μm thick polyether sulfone film by sputtering at a substrate temperature of 30°C. The Si3N4 layer was found to be amorphous by X-ray diffraction. Further, it exhibited a transmittance of 80% or more in the wavelength range of 400 to 850 nm. Next, I
TO was deposited to a thickness of about 1000 Å by sputtering, and then patterned to form a pixel electrode. Next, an MIM element was provided as follows. First, Al was deposited to a thickness of about 1000 Å by vapor deposition and patterned to form the lower electrode 7. On top of that, a hard carbon film was deposited to a thickness of about 1000 Å by plasma CVD as an insulating layer 2, and then dried. Patterned by etching. The conditions for forming the hard carbon film at this time are as follows. Pressure: 0.035TorrCH4 Flow rate:
10 SCCM RF power: 0.2 W/cm2 Furthermore, Ni is deposited on this by approximately 1000 Å by EB evaporation method.
The upper electrode 6 was formed by depositing it thickly and patterning it. In the MIM type devices shown in Examples 1 and 2, no peeling of the film, deformation of the substrate, curling of the substrate, or cracking of the inorganic material was observed. Further, no deterioration was observed even after high temperature storage at 80° C. for 1000 hours.

[0019]

[Effects] Since the present invention is constructed as described above, the thin film laminated device of the present invention does not cause deformation or curling of the substrate, and can achieve low cost and weight reduction. MIM using hard carbon film as insulating layer
When used as a type element, the hard carbon film is 1) Plasma CV
Because it is produced using a vapor phase synthesis method such as the D method, its physical properties can be controlled over a wide range of conditions depending on the film formation conditions, and there is therefore a large degree of freedom in device design.2) It can be made into a hard and thick film;
It is less susceptible to mechanical damage and can be expected to reduce pinholes due to thicker films; 3) It is possible to form high-quality films even at low temperatures near room temperature, so there are no restrictions on the substrate material; 4)
) Excellent uniformity in film thickness and film quality, making it suitable for thin film devices; 5) Low dielectric constant,
It does not require advanced microfabrication technology, and is therefore advantageous for increasing the area of the device.Furthermore, since the dielectric constant is low, the steepness of the device is high, and the Ion/Ioff ratio can be maintained, so it can be driven at a low duty ratio. Therefore, it is suitable as a particularly reliable switching element for liquid crystal display, and is extremely useful industrially.

[Brief explanation of the drawing]

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

[Figure 2] MIM configured by the thin film device of the present invention
FIG. 3 is an explanatory diagram of the main parts of the element.

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

FIGS. 4a and 4b are graphs showing an IV characteristic curve and an lnI-√v characteristic curve, respectively, of the MIM element.

FIG. 5 shows the Gaussian distribution of the IR spectrum of the hard carbon film used as the insulating layer of the MIM device of the present invention.

FIG. 6 is a spectrum diagram showing the results of spectroscopic analysis of the hard carbon film used as the insulating layer of the MIM element of the present invention using an IR absorption method.

FIG. 7 is a spectrum diagram showing the results of Raman spectroscopy analysis of the hard carbon film used for the insulating layer of the MIM element of the present invention.

[Explanation of symbols]

1 Plastic substrate 1' Plastic substrate 2 Hard carbon film 2a Inorganic material layer 2b Inorganic material layer 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

Claims (3)

[Claims] 1. A thin film laminated device comprising: a plastic substrate having thin films made of an inorganic substance formed on both sides; and a thin film laminated device formed on the substrate, wherein the thin film made of the inorganic substance is amorphous. 2. The thin film made of the inorganic substance has a wavelength of 40
The thin film laminated device according to claim 1, having a transmittance of 75% or more in the range of 0 to 850 nm. 3. The thin film stacked device according to claim 1, wherein the thin film stacked device is an MIM type element having a hard carbon film as an insulating layer.