JPH04198916A - Thin-film laminated device - Google Patents

Abstract

PURPOSE:To prevent the deformation of a plastic film substrate, curling, film peeling, etc., and to reduce the cost and weight of the above device by forming inorg. material layers on the plastic film substrate with the thickness enough to cover the surface projecting parts of the substrate. CONSTITUTION:The inorg. material layers 2a, 2b are formed on the plastic film substrate 1 with thickness enough to cover the surface projecting parts of the plastic film substrate 1. SiO2 and Si3N4 are preferable as the inorg. material. These materials are formed at the film thickness larger than the height of the projecting parts of the plastic film substrate 1 and the more preferable thickness is <=10,000Angstrom . The thin-film laminated device which obviates the deformation of the substrate in the element production process, is light in weight and low in cost, and is free from the film peeling and curling is obtd. in this way.

Description

DETAILED DESCRIPTION OF THE INVENTION [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 devices, TVs, and the like.

[Prior art]

There is a strong demand for the use of large-area liquid crystal panels for office automation equipment terminals and liquid crystal TVs, and for this reason, in the active matrix method, 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, forming a thin film laminated switching element on plastic causes deformation and curling of the plastic substrate.
There were problems such as peeling of the film.

In addition, when manufacturing thin film laminated switching elements, there is a process of immersing plastic in solutions such as acids, alkalis, and water, which may leave acids, alkalis, water, etc. in the plastic.
This caused element deterioration.

Furthermore, when a plastic film substrate is used, it becomes difficult to perform the alignment treatment that has been applied to conventional glass substrates.

That is, the orientation treatment methods used for conventional glass substrates include (1) oblique vapor deposition, (2) accelerated ion radiation, (3) rubbing, and (4) stretching film attachment. However, all of these methods cause problems and are no longer preferred.

When a plastic film is used as a substrate, it is necessary to subject its surface to a specific pretreatment (for example, see Japanese Patent Publication No. 1-47769).

〔the purpose〕

An object of the present invention is to solve the conventional problems when using a plastic film substrate, and to provide a thin film laminated device that is lightweight, low cost, and free from peeling and curling.

〔composition〕

In order to achieve the above object, the present inventors considered fabricating a switching element on lightweight and inexpensive plastic, and as a result of repeated research, found that the deformation of the plastic substrate during the element fabrication process is caused by the plastic film. It became clear that curl was the biggest problem. We discovered that the causes of plastic deformation and plastic film curling are internal stress in the laminated thin films, thermal expansion and contraction of the plastic, and swelling due to acids, alkalis, and water.We formed a thin film made of an inorganic substance on both sides. It has become clear that using a plastic substrate is effective.

However, when a thin film made of an inorganic substance is formed on a plastic substrate, a problem arises in that the thin film made of the inorganic substance peels off during the photolithography process when producing a microfabricated thin film stacked device. As a result of various studies, we discovered that the filler contained in plastic and the protrusions on plastic formed by die lines, etc. that occur during molding of plastic film act as nuclei, and the thin film made of the above-mentioned inorganic substance peels off. The inventors have discovered that peeling is effectively eliminated when the thickness of the thin film is greater than the height of the protrusions, leading to the present invention. The filler contained in plastic is mainly C.
a It consists of COs, SiC2, talc, etc., and is used to improve the lubricity, rigidity, and thermal properties of plastics. On the other hand, die lines for plastic films are formed during the extrusion process during extrusion molding.

That is, the present invention relates to a thin film laminated device using a plastic film as a substrate, characterized in that an inorganic material layer is formed on a plastic film substrate with a thickness sufficient to cover the convex portions on the surface of the plastic film substrate.

As a thin film stacked device, an MIM type element with a metal-insulator-metal layer structure, an MSI element (MetaQ-5EYAI-In
sulator), S of semiconductor-insulator-semiconductor layer structure
IS element, metal described in JP-A No. 64-7577
There are MIM elements with one insulator and one metal, and one insulator and one metal. Among these, MIM type elements, especially MIM type elements using a hard carbon film for the N-edge body, are advantageous.6 Examples of inorganic materials include SiC2 and Sl.

N4 is preferred.

In order to produce the thin film laminated device of the present invention, first, 5in2, Si
n, Si:O:N, Si:○:H, Si:N:
H, Si: O: N: H, Si3N4, T
iO2, ZnS, ZnO, AQ, Ol, AflN, Mg
O1Ge○, ZrO23Nb2O,,5iC1Ta20
．． Inorganic materials such as sputtering and vapor deposition methods.

It is formed by a plasma CVD method or the like. The formed thin film has a thickness greater than the height of the convex portion of the plastic film substrate, but preferably has a thickness of 10,000 or less. This is because if the film thickness exceeds 10,000 Å, the film may peel off due to stress, causing problems in adhesion to the plastic film substrate.

The thickness of the plastic is preferably 50 μm to 2 mm.

Next, attach a hard carbon film to the thin film laminated device! A method for manufacturing a thin film laminated device of the present invention using an MIM element as an edge layer will be described in detail.

First, coat one or both sides with the above-mentioned inorganic substance (2
a, 2b) A transparent electrode material for the pixel electrode is deposited on the plastic substrate 1 by a method such as vapor deposition or sputtering, and patterned into a predetermined pattern. A method of forming a conductor thin film for an electrode, patterning it into a predetermined pattern by wet or dry etching to form a first conductor 7 that will become a lower electrode, and covering it with a hard carbon film 2' by a plasma CVD method, an ion beam method, etc. The insulating film is patterned into a predetermined pattern using dry etching, wet etching, or a lift-off method using a resist. Next, a conductor thin film for pass lines is coated on the insulating film by a method such as vapor deposition or sputtering, and then butter is applied to the predetermined pattern. A second conductor 6 is formed as a pass line.Finally, an unnecessary portion of the lower electrode 7 is removed to expose the transparent electrode pattern to form 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 thickness of the lower electrode, upper electrode and transparent electrode is usually
They range from several hundred to several thousand people, several hundred to several thousand people, and several hundred to several thousand people, respectively. The thickness of the hard carbon film is 100 to 8,000, preferably 200 to 5,000, more preferably 300 to 5,000.
The number is in the range of 4,000 people. Alternatively, 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, which becomes the lower electrode, is AQ, Ta.
, Cr, W, Mo, Pt3Ni, Ti, Cu, Au, W
, ITO, ZnO:AIl! .

Various conductors such as In2O, 5n02, etc. are used.

Next, the material of the second conductor 6 which becomes the pass line is AQ.
, Cr3Ni, Mo, Pt+Ag.

Ti, Cu, Au+ W+ Ta, ITO, ZnO:A
Q, I n20. ．． Although various conductors such as 5n02 can be used, Ni, Pt, and Ag are preferred because they have particularly excellent stability and reliability of IV characteristics. The symmetry of the MIM device using a hard carbon film as an insulating film does not change even if the type of electrode is changed, and the relationship QnI''v'v shows that Poole-Frenkel type conduction occurs. This shows that in the case of this type of MIM device, the upper and lower electrodes can be combined in any way.However, the device characteristics (
deterioration and change of IV characteristics) occur. Considering these, 3Ni.

It was found that Pt and Ag are good.

The current-voltage characteristic of the MIM element of the present invention is shown in FIG. 4, and this characteristic is approximately expressed by the conduction equation shown below.

Shi = exp (βV) ... (1)
I: Current V: Applied voltage: Conductivity coefficient β: Poole-Frenkel coefficient n: Carrier density μ: Carrier mobility q
: Charge amount of electron Φnidrap depth ρ : Specific resistance
d: Thickness of insulating film (person) k: Boltzmann constant T:
Ambient temperature ε: dielectric constant of insulating film Next, a method for manufacturing a liquid crystal display device will be described with reference to FIG.

First, a transparent conductor 1 for the common electrode 4', such as ITO, ZnO:Ajl, ZnO:Si, 5nOz, is placed on an insulating substrate 1'.
t Sputtering with In2O3 etc.

It is deposited to a thickness of several hundred to several micrometers by steaming or the like, and patterned into stripes to form the common electrode 4'.

An alignment material 8 such as polyimide is applied to each surface of the substrate 1' on which the common electrode 4' is provided and the substrate 1 on which the MIM elements are provided in a matrix, a rubbing process is performed, a sealing material is applied, and the gap is A material 9 is inserted to maintain a constant gap, and a 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.

In order to form such a hard carbon film, an organic compound gas, particularly a hydrocarbon gas, is used.

The phase state of the raw material does not necessarily have to be a gas phase at room temperature and pressure, but it can be used in either a liquid or solid phase as long as it can be vaporized through melting, evaporation, sublimation, etc. by heating or reduced pressure. It is possible.

Regarding hydrocarbon gas as a raw material gas, for example, CH
4, paraffinic hydrocarbons such as C2H, C, Hlo,
Olefinic hydrocarbons such as C2H4.

Gases containing at least all hydrocarbons such as diolefinic hydrocarbons, acetylenic hydrocarbons, and even aromatic hydrocarbons can be used.

In addition, compounds other than hydrocarbons, such as alcohols, ketones, ethers, esters, etc., can be used as long as they contain at least a carbon element.

In the present invention, the method for forming a hard carbon film from a raw material gas is preferably a method in which active species for film formation are formed through a plasma state generated by a plasma method using direct current, low frequency, high frequency, microwave, etc. However, in order to perform deposition under low pressure for the purpose of increasing the area, improving uniformity, and/or 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 or an ion beam vapor deposition method, or it may be formed from neutral particles generated by a vacuum vapor deposition method, a sputtering method, etc. Furthermore, it may be formed by a combination of these.

An example of the deposition conditions for the hard carbon film produced in this manner is approximately as follows in the case of plasma CVD method.

RF output 20.1~50111/d Pressure: IF”10 Torr Deposition temperature:
It can be carried out at room temperature to 300°C, preferably room temperature to 250°C.

Due to this plasma state, the raw material gas is decomposed into radicals and ions and reacts, thereby forming carbon atoms on the substrate.
A hard carbon film containing at least one of amorphous (non-crystalline) and microcrystalline (crystal size is several 1A to several μm) is deposited. Characteristics of hard carbon film are shown in Table-1.

Note) Measurement method: Specific resistance (ρ): Determined from the IV characteristics using a coplanar cell.

Optical band gap (Egopt): Obtain the absorption coefficient (α) from the spectral characteristics and determine from the relationship (ah v ) = B (h v −Egopt).

Amount of hydrogen in the film (C,): 290 from infrared absorption spectrum
It is determined by integrating the peak around 0■-1 and multiplying it by the absorption cross section A.

That is, SP''/SP2 ratio: infrared absorption spectrum, SP3.S
It is decomposed into Gaussian functions respectively attributed to P2, and determined from the area ratio thereof.

Vickers hardness (H): by micro Vickers meter.
Refractive index (n): by ellipsometer.

Defect density: Based on ESR.

These are shown in graphs in Figures 5.6 and 7.

As a result of analysis using IR absorption and Raman spectroscopy, it was revealed that the hard carbon film thus formed contained a mixture of interatomic bonds that formed the SP3 hybrid orbital and the SP2 hybrid orbital in the carbon atoms. There is. What is the ratio of SP3 bonds to SP2 bonds?

It can be roughly estimated by peak-separating the IR spectrum. The IR spectrum has 2800-31500! l-1
Although the spectra of many modes overlap and are measured,
The attribution of the peaks corresponding to each wavenumber is clear, and by performing peak separation using a Gaussian distribution, calculating the area of each peak, and finding the ratio, S P3/S
P2 can be known.

Further, according to X-ray and electron diffraction analysis, the hard carbon film is in an amorphous state (a-C:H) and/or about 5
It is known that it is in an amorphous state containing microcrystalline grains of about 0 to 5 μm in size.

In the case of plasma CVD method, which is generally suitable for mass production, R
The smaller the F output, the more the specific resistance value and hardness of the membrane increase,
The lower the pressure, the longer the life of the active species, the lower the temperature of the substrate, the more uniform it can be over a large area, and the more specific resistance and hardness tend to increase. Furthermore, since the plasma density decreases at low pressures, methods using magnetic field confinement effects are more effective in increasing resistivity.

Furthermore, this plasma CVD method has the characteristic of being able to form a high-quality hard carbon film even under relatively low temperature conditions of room temperature to 150°C, making it ideal 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 a uniform film can be obtained over a large area to facilitate control of the substrate temperature. Furthermore, since the structure and physical properties of the hard carbon film can be controlled over a wide range, there is also the advantage that device characteristics can be designed freely. Furthermore, the dielectric constant of the film is 2 to 6, which is Ta2O, AM20, which is used in conventional MIM devices.
, is smaller than SiNx, so when creating an element with the same capacitance, the element size only needs to be larger.
It does not require much microfabrication and the yield improves (I
In view of the Ii dynamic conditions, the capacitance ratio between the LCD and the aJIM element must be approximately CLCD/CMIM=10/1. ).

Therefore, if the dielectric constant ε is small, the steepness becomes large,
The ratio between the on-current Ion and the off-current Ioff can be increased. Therefore, LCD with lower duty ratio
I! This makes it possible to realize high-density LCDs. Furthermore, since the film has high hardness, there is little damage caused by the rubbing process during encapsulation of the liquid crystal material, which also improves yield.

In view of 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 as a constituent element an element of Group 1 of the Periodic Table, an element of Group 2 of the Periodic Table, an element of Group 2 of the Periodic Table, an alkali metal element, an alkaline earth metal element, a nitrogen atom, an oxygen atom, a chalcogen-based element, or a halogen atom. The thickness of the hard carbon film is non-doped in the case of introducing an element from Group ■, Group ■, Group ■ of the periodic table, an alkali metal element, an alkaline earth metal element, a nitrogen atom, or an oxygen atom as one of the constituent elements. Approximately 2~
It is possible to increase the thickness by three times, thereby preventing the occurrence of pinholes during device fabrication, and dramatically improving 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 an element of group Ⅰ of the periodic table as described below can be obtained.

Similarly, devices that incorporate elements from group Ⅰ of the periodic table, chalcogen elements, or halogen elements dramatically improve the stability of the hard carbon film and also improve the hardness of the film, resulting in highly reliable elements. can be made. These effects can be obtained because in the case of group Ⅰ elements and chalcogen elements, active double bonds existing in the hard carbon film are reduced, and in the case of halogen elements, 1) abstraction for hydrogen is achieved. The reaction promotes the decomposition of the raw material gas and reduces dangling bonds in the film, and
extracts the hydrogen in the C-H bond and replaces it, C-X
It enters the membrane as a bond, increasing the bond 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, if necessary, dopants such as Group Ⅰ elements of the periodic table, Group Ⅰ elements, and In order to contain Group V elements, alkali metal elements, alkaline earth metal elements, nitrogen atoms, oxygen atoms, chalcogen elements, or halogen elements, compounds (or molecules) containing these elements or atoms (hereinafter referred to as these) [sometimes referred to as other compound j] can be used.

Here, as a compound containing an element of group Ⅰ of the periodic table, for example, B(OC21(S))l azl(l, + BCf1
31 BBr,.

BF,,AΩ(0-i-C,H,)□, (CH,),
Al1. (C2H,)3AL(i-C4H,), AQ
, AnCQ31 Ga(0-i-C)I7)3. (C
H3) 5Gat(C2H,), Ga, GaCQ3.
GaBr,! (0-i-C1l(7)3Inl(c2
H5)! There are r mouths etc.

Examples of compounds containing Group Ⅰ elements of the periodic table include Si.
,H,,(C2H,),SiH,SiF4.5iH2C
Q2゜5ICI2415i (Ocuj4,5l(OC2
H5)415xcoczHt)4tGeCLtGeH
at Ge(OCzHs)4. Ge(CzHs)4+(
CHi)asn+(cznsLsnt 5nCQ4, etc.).

Examples of compounds containing Group V elements of the periodic table include PH
,,PF,, PF5. PCQ2F,, PCQ,,
PCQ2F.

PBr, , PO(OCJ)3r P(C2H5)3
+ POCl23 r ASH3+AsCQ,,As
Br,,AsF,,AsF,,AsCQ,,5bHyr
SbFzrsbc et al., 5b (QC21(, ), etc.).

Examples of compounds containing alkali metal atoms include Li0-
i-C, I7. Na0-i-C, I7. KO-i-C
, Ht, etc.

Examples of compounds containing alkaline earth metal atoms include Ca
C0Cz I5 )3t Mg (OC* I5
)2 + (C2I5)2 Mg, 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 oxide, carbon dioxide, suboxide, and nitrogen oxide.

Inorganic compounds such as nitrogen dioxide, dinitrogen trioxide, dinitrogen pentoxide, nitrogen trioxide, hydroxyl groups, aldehyde groups, acyl groups, ketone groups, nitro groups, nitroso groups, sulfone groups, ether bonds, ester bonds, peptide bonds, Examples include organic compounds having a functional group or bond such as a heterocycle containing oxygen, and metal alkoxides.

Examples of compounds containing chalcogen elements include H2S,
(CI,)(CH2)4S(CI(2)4CH,,C
H2=CHCH25C)12cH=c)I2. C2H
,5C2H,,C2H,SCH3,thiophene,HzS
e+ (czus)zse+ H2Te, etc.

Examples of compounds containing halogen elements include fluorine, chlorine, bromine, iodine, hydrogen fluoride, chlorine fluoride, bromine fluoride, iodine fluoride, hydrogen chloride, bromine chloride, iodine chloride, hydrogen bromide, iodine bromide, Inorganic compounds such as hydrogen iodide, alkyl halides,
Organic compounds such as halogenated aryl, halogenated styrene, halogenated polymethylene, and haloform are used.

A hard carbon film suitable as an MIM element for driving a liquid crystal has a film thickness of 100 to 8000 mm and a specific resistance of 10' depending on the driving conditions.
A range of ˜10 13 Ω·Cl 11 is advantageous. In addition, considering the margin between the driving voltage and the breakdown voltage (dielectric breakdown jl! voltage), it is desirable that the film thickness is 200 Å or more. This is because the film thickness is desirably 6000 Å or less in order to prevent color unevenness from becoming a practical problem.

The thickness of the hard carbon film is 200 to 6000, and the specific resistance is 5X.
More preferably, it is IO' to 1012Ω·C1n.

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 in-plane distribution of film thickness is uniform. (The accuracy of film thickness control is limited to about 30 people, and the variation in film thickness exceeds 10%).
More preferably, it is Å or more.

In addition, in order to make it difficult for the hard carbon film to peel off due to stress, and to lower the duty ratio (preferably 1/
1000 Å or less), the film thickness is more preferably 4000 Å or less.

Taking all of these into consideration, the thickness of the hard carbon film is 30
It is more preferable that the resistivity is 0 to 4000 people and the specific resistance is to' to 1011 Ω·C.

〔Example〕

Although the present invention will be described in detail, the present invention is not limited thereto.

Example 1 As shown in Fig. 1, 70% of Sin was applied to both sides of a 100 μm thick polyarylate film by sputtering.
000 people thick Sin2 layer (2a.

2b) was produced. FIG. 8 shows the surface roughness of the polyarylate film. Approximately 3,000 people had a protrusion with a height of 0. Next, about 1000 ITO was deposited on the SiO2 by a sputtering method, and then patterned to form a pixel electrode.

Next, an MIM element was provided as follows.

First, ann is deposited to about 1,000 octane by vapor deposition method and then finely patterned to form the lower electrode 7. On top of this, a hard carbon film is deposited by plasma CVD to about 1000 octane as an insulating layer 2'.
0008 was deposited and then patterned by dry etching. The conditions for forming the hard carbon film at this time are as follows.

Pressure: 0.035 TorrCH, Flow rate:
20 SCCM RF power: 0.2s/c! Furthermore, approximately 1000 nickels of Ni were deposited on this by EB evaporation and patterned to form the upper electrode 6. No peeling of 5102 was observed during the formation of each fine Everturn.

Example 2 As shown in FIG. 1, both sides of the 100 μm thick polyarylate film 1 used in Example 1 were coated with Si.

S with a thickness of 400OA by sputtering N4
i3N layers (2a, 2b) were prepared. Next, Si3N,
Approximately 1,000 pieces of ITO were deposited thereon by sputtering, and then patterned to form a pixel electrode.

Next, an MIM element was provided as follows.

First, AQ is deposited in about 1,000 layers by vapor deposition, and then finely patterned to form the lower electrode 7. On top of this, a hard carbon film is deposited in about 1,000 layers by plasma CVD as an insulating layer 2'. Life.

Patterned by dry etching. The conditions for forming the hard carbon film at this time are as follows.

Pressure: 0.035 Torr CH4 flow rate:
20 SCCM RF power: 0.2 w/a! Furthermore, approximately 1000 nickels of Ni were deposited on this by EB evaporation and patterned to form the upper electrode 6. No peeling of Si3N4 was observed during the formation of each miniaturized Evaturn.

Comparative Example 1 As shown in FIG. 1, both sides of the 100 μm thick polyarylate film used in Example 1 were coated with Si.

1000mm thick S by sputtering N4
i3N4 layers (2a, 2b) were produced. Next, Si
3N, ITO was applied on top by sputtering method to a thickness of about 1000
After eight layers were deposited, they were patterned to form pixel electrodes.

Next, in order to fabricate an MIM element, AQ is deposited on the lower electrode 7 by a vapor deposition method and then finely patterned.
was formed. However, at that time, peeling of Si3N4 occurred. This is because the thickness of the inorganic material layer of 1000 mm is thinner than the convex portion of the polyarylate film of 3000 mm.
This is because the value of the N4 layer cannot be demonstrated.

Comparative Example 2 As shown in FIG.
, 2b) was prepared. Next, ITO was deposited on the S i 02 to a thickness of about 100 mm by sputtering, and then patterned to form a pixel electrode.

Next, an MIM element was provided as follows.

First, AQ is deposited in about 1,000 layers by vapor deposition and then finely patterned to form the lower electrode 7. On top of this, a hard carbon film of about 1,000 layers is deposited as an insulating layer 2' by plasma CVD.
0008 was deposited and patterned by tri-etching. The conditions for forming the hard carbon film at this time are as follows.

Pressure: 0,035 Torr CH4 flow rate:
20 SCCM RF power: 0.2 w/aj Further, Ni was deposited thereon in a thickness of about 1000 by EB evaporation, and then patterned to form the upper electrode 6. In the photolithography process when forming the Ni pattern, S
i O, peeling occurred.

As is clear from Examples 1 and 2 and Comparative Examples 1 and 2, by forming an inorganic material whose film thickness is larger than the height of the convex portions (protrusions) existing on the surface of the plastic substrate,
It can be seen that a thin film device without film peeling can be fabricated.

〔effect〕

Since the present invention is configured as described above, the thin film laminated device of the present invention is free from deformation of the substrate, curling film peeling, etc., and can achieve low cost and weight reduction, and furthermore, the thin film laminated device can be insulated. MI using a hard carbon film for the layer
When used as an M-type element, the hard carbon film is: 1) Since it is produced by a vapor phase synthesis method such as plasma CVD, the physical properties can be controlled over a wide range by changing the film forming conditions, and therefore there is a large degree of freedom in device design. ) Since it is hard and can be made into a thick film, it is less susceptible to mechanical damage and can be expected to reduce pinholes due to the thicker film. 3) A high-quality film can be formed even at low temperatures near room temperature, so it is suitable for substrate materials. 4) Excellent uniformity in film thickness and film quality, making it suitable for thin film devices. 5) Low dielectric constant, so advanced microfabrication technology is not required, thus allowing for large device area. Furthermore, since the dielectric constant is low, the steepness of the element is high, and the Ion/off ratio can be achieved, so it is possible to drive at a low duty ratio. It is suitable as a switching element for liquid crystal display with high performance.

It is extremely useful in industry.

[Brief explanation of the drawing]

FIG. 1 is a cross-sectional view showing the structure of the thin film device of the present invention;
Figure 2 shows an MIM constructed from the thin film device of the present invention.
FIG. 3 is a partial cross-sectional perspective view of a liquid crystal display incorporating the thin film device of the present invention; FIGS. 4 a and b are IV characteristic curves of the M r M element, 12nrv' FIG. 5 is a spectrum diagram showing the results of Raman spectroscopy analysis of the hard carbon film used for the insulating layer of the MIM device of the present invention, and FIG. 6.7 is a graph showing the v characteristic curve. It is a spectrum diagram showing the analysis results of the hard carbon film used for the insulating layer of the MIM element of the invention by IR absorption method and Raman spectroscopy. FIG. 8 is a diagram showing the surface roughness of the polyarylate film used in the examples. 1.1'...Insulating substrate 2'...Hard carbon film 2a
, 2b... Inorganic substance 3... Liquid crystal 4... Pixel electrode 4'... Common electrode 5... Active element (MIM element) 6... Second conductor (pass line) (upper electrode) 7... First
Conductor (lower electrode) 8... Alignment film 9... Gap material patent applicant Ricoh Co., Ltd. -- Nigo -- Representative patent attorney Tomo Hide Matsu - :--Ichingo, ゛7 Gohiro/ Figure 1 Figure 2 Figure 3 Figure 4 ((1) (b) Figure 5 0m-1 (Wataru) Figure 6 Figure 7 Raman spectrum (7&1

Claims (1)

[Scope of Claims] 1. A thin film laminated device using a plastic film as a substrate, characterized in that an inorganic material layer is formed on the plastic film substrate with a thickness sufficient to cover the convex portions on the surface of the plastic film substrate. 2. The thin film laminated device using a plastic film as a substrate according to claim 1, wherein the thin film laminated device is an MIM type element having a hard carbon film as an insulating layer. 3. The inorganic material layer is SiO_2 and/or Si_
A thin film laminated device using the plastic film according to claim 1 or 2 as a substrate, which is composed of 3N_4.