JPH04348090A - Thin film laminated device with substrate - Google Patents

Abstract

PURPOSE:To remove film separation, curls, etc., and seek weight reduction, cost cutdown, and improvement of reliability by putting a substrate in multilayer structure, in a thin film multilayered device made on the substrate. CONSTITUTION:First, a transparent electrode material for picture element electrode is deposited on a multilayer structure, for example, a substrate consisting of glass 11 and polylate 12 by the method of sputtering, etc., and are patterned and are made a picture element electrode. Next, a conductor film for lower electrode is made by the method of deposition or the like, and is patterned into the first conductor 7 to become the lower electrode. It is covered with a hard carbon film 2 by plasma CVD method or the like, and then it is patterned by dry etching into an insulating film. It is covered with a conductor film for bus line by the method of deposition or the like, and it is patterned into the second conductor 6, and the needless part of the lower electrode is removed to expose the transparent electrode pattern, and this is made a picture electrode. Hereby, there never occurs deformation, curl, or pattern dislocation of a substrate, and cost reduction and weight reduction can be achieved.

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. On the other hand, when the glass substrate is made thinner to about 100 μm to reduce its weight, there is a problem that the glass substrate easily breaks during the process of manufacturing a thin film laminated device. Further, even if a thin film laminated device is fabricated on a thin glass substrate, there is a problem in that cracks occur during subsequent device mounting.

0003

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

0004

[Structure] In order to achieve the above object, the present inventors
As a result of repeated research and consideration of fabricating switching elements on lightweight, inexpensive plastic, it became clear that curling is the biggest problem when using plastic film due to the deformation of the plastic substrate during the element fabrication process. . 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. Furthermore, when a thin film laminated device is microfabricated on the above-mentioned substrate, there is a problem in that pattern shift and expansion/contraction anisotropy occur due to expansion and contraction of the plastic substrate. To summarize the technical issues when forming thin film laminated devices on these plastic substrates: 1) Adhesion between the plastic substrate and thin film laminated devices;
2) deformation (curl) of the plastic during the fabrication of thin film stacked devices; 3) pattern deviation due to expansion and contraction of the plastic substrate during microfabrication processing. It has been extremely difficult to solve these technical problems by using one type of plastic substrate. As a result, the present inventors found that it is effective to use a substrate laminated with materials suitable for solving each of these problems and to fabricate a thin film laminated device thereon, thereby completing the present invention. That is, the present invention relates to a thin film laminated device with a substrate and a thin film laminated device formed on the substrate, wherein the substrate has a multilayer structure. The thin film stacked device is preferably an MIM element having a hard carbon film as an insulating layer. Furthermore, it is more preferable that at least one layer of the substrate having a multilayer structure is a plastic layer. The combination of each layer of a multilayered substrate varies depending on the purpose of solving the problem, but in general, the layers of the substrate that make up the part in contact with the thin film stacked device have good adhesion to the thin film stacked device and surface smoothness. A material group that can ensure properties and structural isotropy is preferable. Specific examples include glass, polyarylate, polycarbonate, polyether sulfone, and polymethyl methacrylate. The layers of the substrate constituting the portions not in contact with the thin film stacked device are preferably made of materials with high rigidity in order to reduce deformation and curling of the substrate. Specifically, glass, polyethylene terephthalate, polyimide, etc. can be used. However, it is not preferable for both layers to be made of glass from the viewpoint of weight reduction. Additionally, adhesive layers or barrier layers against water and oxygen may optionally be incorporated between the layers. Fluororesin or the like is used for the barrier layer. Among the substrates having the above-mentioned layer structures, an effective layer structure is a combination of glass and plastic. This combination is effective whether the thin film laminated device is fabricated on either a glass surface or a plastic surface. When manufacturing thin film laminated devices on thin glass substrates with the aim of reducing the weight of thin film laminated devices, the presence of plastic on the back side of the glass prevents them from breaking easily even if the glass substrate is thin. Furthermore, even when a thin-film stacked device is formed on a plastic surface, the presence of highly rigid glass on the back side of the plastic eliminates the substrate deformation, curling, and handling difficulties that are seen with substrates made solely of plastic. In consideration of handling, substrate deformation, and weight reduction, in the case of a substrate made of two layers of glass and plastic, the thickness is preferably 200 μm or less for glass and 300 μm or less for plastic. A laminated structure of glass and plastic is also effective in a structure with three or more layers. The plastic/glass/plastic configuration is effective in terms of impact resistance. A substrate having a laminated structure of glass and plastic is produced by forming a polymer layer such as polyarylate, polycarbonate, polyether sulfone, etc. to a predetermined thickness on one or both sides of Pyrex glass having a thickness of about 150 μm by a casting method. Alternatively, it is also possible to bond plastic and glass using an epoxy adhesive. A substrate having a layered structure of several types of plastics can be bonded using solvents, heat, adhesives, etc., and is manufactured by selecting an appropriate bonding method depending on the physical properties of the plastic. Further, a lightweight and flexible substrate can be manufactured by a method as shown in FIG. After preparing the thin film laminated device 14 in advance on a thick glass substrate 11 of 500 μm or more {FIG. 8(a)}, the thin film laminated device portion is protected by coating with resist or polymer 13 {FIG. 8(b)}, The back surface of the glass substrate is etched or polished to make the glass substrate part several μm thick {Fig. 8(c)}, and a plastic layer is cast on it or a plastic plate (film) is bonded with adhesive {Fig. 8(c)}. (d)}.Finally, the resist or polymer 13 is removed using a solvent, etc., and the thin film laminated device 1 is placed on the substrate laminated with the glass 1 and the plastic layer 12.
4 is produced {FIG. 8(e)}. The resist or polymer 13 protects the thin film stacked device 14 (c
) It serves as a reinforcing member to prevent the thin film laminated device from deforming when the glass becomes thinner in the step ( ). This method allows thin film laminated devices to be fabricated directly on glass substrates, so the expansion and contraction of the substrate is small, resulting in smaller pattern deviations.
At the same time, flexibility can be ensured.

Next, a method for manufacturing the substrate-attached thin film laminated device of the present invention will be explained in detail with reference to FIGS. 1 to 3. First, a transparent electrode material for a pixel electrode is vapor-deposited on a multilayered substrate made of glass 11 and polyarylate 12.
It is deposited by a method such as sputtering and patterned into a predetermined pattern to form the 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. After coating the hard carbon film 2 by a method such as a dry etching method, it is patterned into a predetermined pattern by dry etching, wet etching, or a lift-off method using a resist to form an insulating film, and then a bus line conductor is formed on the insulating film by a method such as vapor deposition or sputtering. A thin film is coated and patterned into a predetermined pattern to form a second conductor 6 that will become a bus line.Finally, an unnecessary portion of the lower electrode is removed to expose a transparent electrode pattern to form a 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 thickness of the lower electrode, upper electrode, and transparent electrode is usually several hundred to several thousand Å, and several hundred to several thousand Å, respectively.
It ranges from several thousand Å to several hundred to several thousand Å. The thickness of the hard carbon film is 100 to 8000 Å, preferably 200 to 6000 Å.
Å, more preferably in the range of 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 1 serving as the lower electrode includes Al, Ta, Cr, W, Mo, and Pt.
, Ni, Ti, Cu, Au, W, ITO, ZnO:Al
, In2O3, SnO2, etc. are used.

Next, the materials for the second conductor 3 that will become the bus line include Al, Cr, Ni, Mo, Pt, Ag, Ti,
Cu, Au, W, Ta, ITO, ZnO:Al, In2
Various conductors such as O3 and SnO2 are used, but I-V
Ni, because of its particularly excellent stability and reliability of properties,
Pt and Ag are preferred. In the MIM element using the hard carbon film 2 as an insulating film, the symmetry does not change even if the type of electrode is changed, and it can be seen from the relationship lnI∝√v that Poole-Frenkel type conduction is performed. Also, from this fact, this kind of M
It can be seen that in the case of an IM element, the upper electrode and lower electrode may be combined in any manner. 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, Ni, P
It was found that t,Ag is 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: Film thickness of hard carbon (Å) k: Boltzmann constant T: Ambient temperature ε1: Dielectric constant of hard carbon ε2: Vacuum permittivity Next, the liquid crystal display is shown in Figure 3. The method for manufacturing the device will be described. first,
A transparent conductor for the common electrode 4', for example I
TO, ZnO:Al, ZnO:Si, SnO2, In2
O3 or the like is deposited to a thickness of several hundred Å to several μm by sputtering, vapor deposition, etc., and patterned into stripes to form the common electrode 4'.
shall be. The substrate 1' provided with this common electrode 4' and the MI
An alignment material 8 such as polyimide is applied to the surface of each substrate 1 on which M 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, and a liquid crystal 3 is sealed. and use it as a liquid crystal display device. In this way, a liquid crystal display device is obtained.

The hard carbon film in 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 the hydrocarbon gas as the raw material gas, for example, paraffinic hydrocarbons such as CH4, C2H6, C3H8, C4H10, acetylene hydrocarbons such as C2H2, etc.
Gases containing at least all hydrocarbons such as olefinic hydrocarbons, diolefinic hydrocarbons, and even aromatic hydrocarbons can be used. 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.

[0011]

[Table 1]

Note) Measurement method; Specific resistance (ρ): I-V using a coplanar cell
Determined from characteristics. Optical bandgap (Egopt): Obtain the absorption coefficient (α) from the spectral characteristics and determine from the relationship shown in Equation 2.

[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 micro Vickers meter. Refractive index (n): By ellipsometer. Defect density: Based on ESR.

The hard carbon film thus formed was analyzed by IR absorption method and Raman spectroscopy, and the results are shown in FIGS. 5 and 6, respectively.
and 7, the carbon atom has a hybrid orbital of SP3 and SP
It has become clear that there are interatomic bonds that form a hybrid orbital of 2. The ratio of SP3 bonds to SP2 bonds can be approximately estimated by peak-separating the IR spectrum. IR spectrum includes 2800-3150/c
Although the spectra of many modes overlap in the measurement, the attribution of the peak corresponding to each wave number is clear, and the peak area is calculated by separating the peaks using a Gaussian distribution as shown in Figure 5. , if you find the ratio, S
You can know P3/SP2. 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,
A method using the magnetic field confinement effect is 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 Ta2, which is used in conventional MIM devices.
Since it is smaller than O5, Al2O3, and SiNx, when making an element with the same capacitance, the element size only needs to be larger, so microfabrication is not required and the yield is improved (due to 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 is 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, LC with lower duty ratio
D drive becomes possible 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.

Furthermore, this hard carbon film contains, in addition to carbon atoms and hydrogen atoms, Group III elements, Group IV elements, Group V elements of the periodic table, alkali metal elements, alkaline earth metal elements, and nitrogen atoms. , an oxygen element, a chalcogen-based element, or a halogen atom may be included as a constituent element. 1 of the constituent elements
Group III elements of the periodic table, as well as group V elements,
Those into which alkali metal elements, alkaline earth metal elements, nitrogen atoms, or oxygen atoms are introduced can make the hard carbon film about 2 to 3 times thicker than non-doped ones.
Moreover, 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 film, and the bond energy increases (the bond energy between C-H and C-X is
This is because the distance between X is larger. In order to use these elements as constituent elements of the film, in addition to hydrocarbon gas and hydrogen as raw material gases, it is necessary to add elements from periodic table I as dopants to the film.
In order to contain a group II element, a group IV element, a group V element, an alkali metal element, an alkaline earth metal element, a nitrogen atom, an oxygen atom, a chalcogen element, or a halogen element, these elements or atoms are added. Compounds (or molecules) containing (
Hereinafter, these gases may also be referred to as "other compounds").

Examples of compounds containing Group III elements of the periodic table include B(OC2H5)3, B2H6, B2H6, and
Cl3, BBr3, BF3, Al(O-i-C3H7)
3, (CH3)3Al, (C2H5)3Al, (i-C
4H9)3Al,AlCl3,Ga(O-i-C3H7
)3, (CH3)3Ga, (C2H5)3Ga, GaC
l3, GaBr3, (O-i-C3H7)3In, (C
2H5)3In etc. Examples of compounds containing Group IV elements of the periodic table include Si2H6, (C2H5)3S
iH, SiF4, SiH3Cl, SiCl4, Si(O
CH3)4,Si(OC2H5)4,Si(OC3H7
)4, GeCl4, GeH4, Ge(OC2H5)4,
Ge(C2H5)4, (CH3)4Sn, (C2H5)
4Sn, SnCl4, etc. Examples of compounds containing Group V elements of the periodic table include PH3, PF3, PF5, P
Cl2F3, PCl3, PCl2F, PBr3, PO(
OCH3)3, P(C2H5)3, POCl3, AsH
3, AsCl3, AsBr3, AsF3, AsF5, A
sCl3, SbH3, SbF3, SbCl3, Sb(O
C2H5)3 etc. Examples of compounds containing alkali metal atoms include LiO-i-C3H7, NaO-i-
There are C3H7, KO-i-C3H7, etc. Examples of compounds containing alkaline earth metal atoms include Ca(OC2H
5) 3, Mg(OC2H5)2, (C2H5)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,
Organic compounds having functional groups or bonds such as hydroxyl groups, aldehyde groups, acyl groups, ketone groups, nitro groups, nitroso groups, sulfone groups, ether bonds, ester bonds, peptide bonds, heterocycles containing oxygen, metal alkoxides, etc. can be mentioned. Compounds containing chalcogen elements include:
For example, H2S, (CH3) (CH2)4S (CH2)4
CH3,CH2=CHCH2SCH2CH=CH2,C
2H5SC2H5, C2H5SCH3, thiophene, H
There are 2Se, (C2H5)2Se, and H2Te. Compounds containing halogen elements include, for example, fluorine, 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, and other inorganic compounds, halogens Organic compounds such as alkyl halides, aryl halides, styrene halides, polymethylene halides, and haloform are used.

[0016] A hard carbon film suitable as a liquid crystal driving MIM element has a film thickness of 100 to 8000 Å and a specific resistance of 10 6 to 10 13 Ω·cm, depending on the 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 100 to 6000 Å,
More preferably, the specific resistance is 5×10 6 to 10 13 Ω·cm. The number of device defects due to pinholes in a hard carbon film increases as the film thickness decreases, and becomes especially noticeable below 300 Å (defect rate exceeds 1%);
Uniformity of in-plane distribution of film thickness (and therefore uniformity of device characteristics)
(The accuracy of film thickness control is limited to about 30 Å, and the variation in film thickness exceeds 10%). Therefore, it is more desirable that the film thickness is 300 Å or more. In addition, in order to make the hard carbon film less likely to peel off due to stress, and to lower the duty ratio (preferably 1/1000
(below), it is more desirable that the film thickness be 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 10.
More preferably, it is 7 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, a 75 μm thick polyarylate 12 layer was formed on the back surface of a 120 μm thick glass substrate 11 by a casting method. Next, ITO was applied to the surface of the glass substrate.
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, approximately 1% Al was deposited by vapor deposition.
After depositing to a thickness of 0.000 Å, a lower electrode 7 is formed by patterning, and a hard carbon film is deposited on top of it as an insulating layer 2 using plasma carbon.
After depositing the film to a thickness of about 1000 Å using the VD method, it was patterned using dry etching. The conditions for forming the hard carbon film at this time are as follows. Pressure: 0.035 Torr
CH4 flow rate: 10 SCCMRF power: 0.2 w/cm2 Furthermore, N on top of this
After depositing i to a thickness of about 1000 Å by EB evaporation, it was patterned to form the upper electrode 6. At this time, no pattern deviation occurred. In addition, there was no deformation of the substrate throughout the entire process, and it was easy to handle. Example 2 Approximately 10% of ITO was deposited on a glass substrate by sputtering method.
After depositing to a thickness of 0.00 Å, it was patterned to form a pixel electrode. Next, the MIM element 14 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 this, 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: 0.035 Torr
CH4 flow rate: 10 SCCMRF power: 0.2 w/cm2 Furthermore, N on top of this
After depositing i to a thickness of about 1000 Å by EB evaporation, it was patterned to form the upper electrode 6 {FIG. 8(a)}. Next, as shown in FIG. 8(b), a resist 13 was formed to a thickness of 50 μm on the MIM element 14 by a casting method. Next, the back surface of the glass substrate 11 was thinned to about 5 μm with hydrofluoric acid {FIG. 8(c)}. Next, a polyarylate layer 12 having a thickness of 100 μm was formed on the back surface of the thinned glass substrate 11 by a casting method. Next, the 50 μm thick resist 13 on the element 14 was removed using a peeling solution. In this way, an MIM element 1 having a hard carbon film as an insulator is placed on a thin glass substrate 11 having a plastic layer 12 on the back surface.
4 could be manufactured without any pattern deviation. Moreover, this substrate-attached MIM device was lightweight and had excellent flexibility.

[0018]

[Effects] Since the present invention is constructed as described above, the thin film laminated device of the present invention is free from substrate deformation, curling, and pattern shift, and can achieve low cost and weight reduction. When the device is an MIM type element using a hard carbon film as an insulating layer, the hard carbon film is manufactured by 1) a vapor phase synthesis method such as plasma CVD method, so the physical properties can be controlled over a wide range by changing the film forming conditions; Therefore, there is a large degree of freedom in device design. 2) Since the film can be made hard and thick, it is less susceptible to mechanical damage, and pinholes can be expected to be reduced by thickening the film. 3) Good quality even at low temperatures near room temperature. 4) Excellent uniformity in film thickness and film quality, making it suitable for thin film devices; 5) Low dielectric constant, making it suitable for advanced microfabrication technology It is advantageous for increasing the area of the device, and 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 drawings]

FIG. 1 is a cross-sectional view showing the structure of a thin film laminated device with a substrate according to the present invention.

FIG. 2 is an explanatory diagram of a main part of an MIM element configured by a thin film laminated device with a substrate according to the present invention.

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

FIG. 4: a is the IV characteristic curve of the MIM device, b is lnI
It is a graph showing a −√v characteristic curve.

FIG. 5 shows the Gaussian distribution according to 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 an IR absorption spectroscopy analysis of the hard carbon film used as the insulating layer of the MIM element of the present invention.

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

FIGS. 8(a) to 8(e) show steps for manufacturing a thin film laminated device with a substrate according to the present invention.

[Explanation 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 11 Glass substrate 12 Plastic layer 13 Resist

Claims (3)

[Claims] 1. A thin film laminated device with a substrate, characterized in that the substrate has a multilayer structure. 2. The thin film laminated device with a substrate according to claim 1, wherein the thin film laminated device is an MIM element having a hard carbon film as an insulating layer. 3. The thin film laminated device with a substrate according to claim 1, wherein at least one layer of the substrate having a multilayer structure is a plastic layer.