JP6848496B2 - Laminate - Google Patents

Description

The present invention relates to a laminate of an inorganic substrate used as a temporary support substrate when forming an electronic device and a heat-resistant polymer film which can form a part of an electronic device, particularly when exposed to a high temperature during device formation. Also, the present invention relates to a laminate capable of peeling a heat-resistant polymer film layer from an inorganic substrate without stress.

In recent years, technological development for forming these elements on a polymer film has been actively carried out for the purpose of reducing the weight, making the size and thickness of functional elements such as semiconductor elements, MEMS elements, and display elements, and increasing the flexibility. That is, as a material for a base material of electronic parts such as information communication equipment (broadcasting equipment, mobile radio, mobile communication equipment, etc.), radar, high-speed information processing equipment, etc., conventionally, it has heat resistance and a signal of the information communication equipment. Ceramics that can handle higher frequencies in the band (reaching the GHz band) have been used, but since ceramics are not flexible and difficult to thin, there is a drawback that the applicable fields are limited, so recently A polymer film is used as a substrate.

When forming functional elements such as semiconductor elements, MEMS elements, and display elements on the surface of polymer films, it is ideal to process them by a so-called roll-to-roll process that utilizes the flexibility that is a characteristic of polymer films. It is said that. However, in industries such as the semiconductor industry, MEMS industry, and display industry, process technologies for rigid flat substrates such as wafer-based or glass substrate-based have been constructed so far. Therefore, in order to form a functional element on a polymer film using the existing infrastructure, the polymer film is bonded to a rigid support made of an inorganic substance such as a glass plate, a ceramic plate, a silicon wafer, or a metal plate. A process is used in which a desired element is formed on the element and then peeled off from the support.

By the way, in the process of forming a desired functional element in a laminated body in which a polymer film and a support made of an inorganic substance are bonded together, the laminated body is often exposed to a high temperature. For example, in forming a functional element such as polysilicon or an oxide semiconductor, a process in a temperature range of about 200 ° C. to 600 ° C. is required. Further, in the production of a hydrogenated amorphous silicon thin film, a temperature of about 200 to 300 ° C. may be applied to the film, and further, in order to heat and dehydrogenate the amorphous silicon to obtain low temperature polysilicon, the temperature is about 450 ° C. to 600 ° C. Heating may be required. Therefore, the polymer film constituting the laminate is required to have heat resistance, but as a practical matter, the polymer film that can withstand practical use in such a high temperature range is limited. In addition, it is generally conceivable to use an adhesive or an adhesive for bonding the polymer film to the support, but at that time, the bonding surface between the polymer film and the support (that is, the adhesive for bonding) Adhesive) is also required to have heat resistance. However, since ordinary adhesives and adhesives for bonding do not have sufficient heat resistance, bonding with an adhesive or adhesive cannot be applied when the formation temperature of the functional element is high.

Since there is no heat-resistant adhesive means for attaching the polymer film to the inorganic substrate, in such applications, a polymer solution or a polymer precursor solution is applied onto the inorganic substrate and dried / cured on the support to form a film. , The technology used for the application is known. In order to further facilitate peeling, a technique of forming a plurality of layers and using a part as a sacrificial layer, or a technique of separating the adhesive / peeling function from the physical characteristics of the film has been proposed (patented). Documents 1 to 3).

However, since the polymer film obtained by such means is brittle and easily torn, the functional element formed on the surface of the polymer film is often broken when peeled from the support. In particular, it is extremely difficult to peel off a large-area film from a support, and it is not possible to obtain a yield that is approximately industrially viable. In view of these circumstances, as a laminate of a polymer film and a support for forming a functional element, a polyimide film having excellent heat resistance, toughness, and thinning ability can be obtained from an inorganic substance via a silane coupling agent. A laminate formed by bonding to a support (inorganic layer) has been proposed (Patent Documents 4 to 5).

Japanese Unexamined Patent Publication No. 2016-120629 Japanese Unexamined Patent Publication No. 2016-20630 Japanese Patent No. 4834758 Japanese Unexamined Patent Publication No. 2010-283262 Japanese Unexamined Patent Publication No. 2011-11455

Based on the technical background described above, in the process of forming an electronic device on a polymer film, it is better that the processing temperature is high in order to obtain a high-quality crystalline thin film, but the heat resistance of the polymer film is high. In view of the properties, the conditions have been set in the balance of contradictory factors that the heating temperature should be kept to the minimum necessary. However, since it has become possible to use a heat-resistant polymer film having good physical properties instead of a process using a precursor solution, a demand for further raising the processing temperature has become apparent from the electronic device manufacturing technology side. There is. That is, there is a growing demand for the heat treatment temperature, whose upper limit has been suppressed to 400 ° C. to less than 450 ° C., to be 450 ° C. or higher, preferably 500 ° C. or higher, preferably 510 ° C. or higher.

When the heat treatment is applied at such a high temperature, the present inventors have more influence of high temperature exposure on the adhesive interface between the polymer film and the inorganic substrate than the problem of thermal deterioration of the polymer film, and the peel strength It was expected that the amount would drop too much and the trouble of peeling off the polymer film during the process would occur frequently.
However, in reality, the adhesive strength between the polymer film and the inorganic substrate increases, and the problem of difficulty in peeling is more serious.
The phenomenon that the peel strength increases is that many heat-resistant polymers are condensation-type polymers, and the decomposition reaction and recombination reaction are balanced even in the temperature range of around 500 ° C, where ordinary polymers are likely to decompose. On the other hand, since high temperature induces very high chemical activity, it can be interpreted that some kind of chemical bond occurs between the surface of the inorganic substrate and the activated heat-resistant polymer.

As a result of diligent studies to solve the above problems, the present inventors have made the change width of the peel strength due to the heat treatment at a high temperature within a predetermined range, so that the device does not cause a peel accident during the processing process and at the same time. We have arrived at the present invention by finding that the device can be easily peeled off from the inorganic substrate together with the polymer film after the formation.

That is, the present invention has the following configuration.
[1] A laminate of a heat-resistant polymer film and an inorganic substrate, which has the initial peel strength between the heat-resistant polymer film and the inorganic substrate and the peel strength when cooled to room temperature after being heat-treated at 450 ° C. in a nitrogen environment. Is a laminate characterized by satisfying the following relational expression.
0.05 ≤ F0 ≤ 3.00
dFt = (Ft−F0) / t
−0.15 ≦ dFt ≦ + 0.15
0.02 ≤ Ft
Here, F0 [N / cm]: Initial peel strength t [hr]: Heat treatment time at 450 ° C. in a nitrogen environment An integer in the range of 1 to 3 Ft [N / cm]: Peel strength after heat treatment t hours [ 2] A laminate of a heat-resistant polymer film and an inorganic substrate, the initial peel strength of the heat-resistant polymer film and the inorganic substrate, and the peel strength when cooled to room temperature after heat treatment at 510 ° C. in a nitrogen environment. A laminate characterized by satisfying the following relational expressions.
0.05 ≤ F0 ≤ 3.00
dFs = (Fs−F0) / s
−0.15 ≦ dFs ≦ + 0.15
0.02 ≤ Fs
Here, F0 [N / cm]: Initial peel strength s [hr]: Heat treatment time in a nitrogen environment at 510 ° C. An integer in the range of 1 to 3 Fs [N / cm]: Peel strength after heat treatment s time [ 3] The laminate according to [1] or [2], which has a silane coupling agent layer between the heat-resistant polymer film and the inorganic substrate.
[4] Any of [1] to [3], which comprises having at least one metal thin film layer selected from molybdenum, tungsten, and chromium between the silane coupling agent layer and the inorganic substrate. The laminate described in.
[5] The laminate according to any one of [1] to [4], which has an aluminum oxide layer between the silane coupling agent layer and the inorganic substrate.
[6] The laminate according to any one of [1] to [4], which comprises having a silicon compound layer between the silane coupling agent layer and the inorganic substrate.
[7] The laminate according to any one of [1] to [4], which comprises having a composite oxide layer of aluminum and silicon between the silane coupling agent layer and the inorganic substrate.
[8] It is selected from at least aluminum oxide, aluminum nitride, silicon oxide, silicon nitride, and a composite oxide of aluminum and silicon between the silane coupling agent layer and the inorganic substrate on the side in contact with the silane coupling agent layer. It is characterized by having a thin film layer containing one or more materials and a thin film layer containing at least one or more materials selected from at least molybdenum, tungsten, silicon, and nickel-chromium alloy on the side in contact with the inorganic substrate [1]. To the laminate according to any one of [3].
[9] Between the silane coupling agent layer and the inorganic substrate, at least an oxide thin film made of aluminum oxide or silicon oxide on the side in contact with the silane coupling agent layer, and at least molybdenum, tungsten, on the side in contact with the inorganic substrate. The laminate according to any one of [1] to [3], which comprises a metal thin film containing one selected from chromium and nickel-chromium alloys.
[10] The laminate according to any one of [1] to [9], which is used as a temporary support substrate for forming an electronic device.

Further, the present invention preferably has the following configuration.
[11] A laminate of a heat-resistant polymer film and an inorganic substrate, the initial peel strength of the heat-resistant polymer film and the inorganic substrate, and the peel strength when cooled to room temperature after being heat-treated at 510 ° C. in a nitrogen environment. Is a laminate characterized by satisfying the following relational expression.
0.05 ≤ F0 ≤ 3.00
dFu = (Fu-F0) / u
−0.15 ≦ dFu ≦ + 0.15
0.02 ≤ Fu
Here, F0 [N / cm]: Initial peel strength u [hr]: Heat treatment time in a nitrogen environment at 510 ° C. An integer in the range of 1-3 Fu [N / cm]: Peel strength after heat treatment u hours

The effect of the present invention is, firstly, to prevent peeling accidents even during the processing process by guiding the change in peeling strength during high temperature treatment to a pattern satisfying a specific mathematical formula described in the claims, and at the same time, device formation. Later, it was realized that the device could be easily peeled off from the inorganic substrate together with the polymer film.
The specific means for deriving the change pattern of the peel strength will be described in detail, but basically, the peel strength is obtained by inserting a specific thin film layer between the polymer film and the inorganic substrate. Achieve a change pattern. The thin film layer is preferably accompanied by a silane coupling agent layer, more preferably at least one layer or more of inorganic substances, and more preferably two or more inorganic thin film layers in addition to the silane coupling agent layer.

The thin film layer in the present invention has high affinity when laminating a heat-resistant polymer film, preferably when applying a silane coupling agent solution, more preferably when applying a polymer compound precursor solution, or when laminating a precursor film. Wetting at the interface (the concept of wetting here can be applied not only to liquids but also to plastically deformed layers existing on solid surfaces at the molecular level) promotes stable initial adhesion.
On the other hand, the chemical affinity for the silane coupling agent layer in which the condensation reaction has occurred or the polymer film layer in a stationary state without physical change is low in a wide temperature range and high even when high temperature heat treatment is applied. It does not significantly affect the peel strength between the molecular film layer and the inorganic substrate layer.

In the present invention, it is selected from at least aluminum oxide, aluminum nitride, silicon oxide, silicon nitride, and a composite oxide of aluminum and silicon on the side in contact with the silane coupling agent layer, particularly between the silane coupling agent layer and the inorganic substrate. When the structure has a thin film layer containing one or more materials and a thin film layer containing at least one or more materials selected from at least molybdenum, tungsten, chromium, and nickel-chromium alloy on the side in contact with the inorganic substrate, the oxide Alternatively, a stable weak adhesive layer is formed between the nitride layer and the metal thin film. In particular, a thin film layer containing one or more materials selected from molybdenum, tungsten, chromium, and nickel-chromium alloys used in the present invention has a stable passivation formed on the surface, and such passivation is caused by an oxide thin film layer and a nitride. A stable weakly bonded state is formed with the thin film layer, and since the reactivity is low, the weakly bonded state does not change even when exposed to a high temperature for a long time, and as a result, stable peeling performance can be maintained. ..

As a result, in the region that falls into the peel strength change pattern during the high temperature treatment of the present invention, it occurs not only to prevent peeling accidents during the process but also when gas is generated from the polymer film during the high temperature heat treatment. It achieves both the minimum necessary adhesiveness that can suppress swelling (or bubbles, blister) and good peeling performance that allows peeling without giving stress to the device part.

Further, according to the present invention, by forming the thin film into a predetermined pattern, the surface on which the polymer film is laminated is a region where the polymer film can be easily separated from the inorganic substrate by making a cut in the polymer film. A functional element portion formed on the polymer film of the easily peelable portion by making a notch along the periphery of the easily peelable portion and making a good adhesive portion which is a region that cannot be easily separated. Can be peeled off from the inorganic substrate integrally with the polymer film.
By using the polymer film laminated substrate of the present invention, a flexible printed wiring board, a TAB tape, a COF, a dielectric element, a semiconductor element, a MEMS element, a display element, a light emitting element, a photoelectric conversion element, a piezoelectric conversion element, a thermoelectric conversion element, High-yield production of flexible electronic devices in which electromagnetic induction elements, print coils, print antennas, biosensors, electronic devices such as their composite elements, electromechanical devices, active elements, passive elements, etc. are formed on a polymer film. It becomes feasible at.

It is a schematic schematic diagram which shows an example of the silane coupling agent coating apparatus by the gas phase method of this invention.

<Inorganic substrate>
In the present invention, an inorganic substrate is used as a support for the polymer film. Further, even in the case of forming an electronic device on a polymer film to manufacture a flexible electronic device, the inorganic substrate is used to temporarily support the polymer film material.
The inorganic substrate may be a plate-like substrate that can be used as a substrate made of an inorganic substance. For example, a glass plate, a ceramic plate, a semiconductor wafer, a metal or the like, and these glass plates, ceramic plates, etc. Examples of semiconductor wafers and composites of metals include those in which these are laminated, those in which they are dispersed, and those in which these fibers are contained.

Examples of the glass plate include quartz glass, high silicate glass (96% silica), soda lime glass, lead glass, aluminoborosilicate glass, borosilicate glass (Pylex (registered trademark)), borosilicate glass (non-alkali), and the like. Borosilicate glass (microsheet), aluminosilicate glass and the like are included. Among these, those having a coefficient of linear expansion of 5 ppm / K or less are desirable, and if it is a commercially available product, "Corning (registered trademark) 7059" or "Corning (registered trademark) 1737" manufactured by Corning Inc., which is glass for liquid crystal, "EAGLE", "AN100" manufactured by Asahi Glass Co., Ltd., "OA10" manufactured by Nippon Electric Glass Co., Ltd., "AF32" manufactured by SCHOTT Co., Ltd., etc. are desirable.

The semiconductor wafer is not particularly limited, but is limited to silicon wafer, germanium, silicon-germanium, gallium-arsenic, aluminum-gallium-indium, nitrogen-phosphosphide-antimony, SiC, InP (indium phosphorus), InGaAs, GaInNAs, and the like. Wafers such as LT, LN, ZnO (zinc oxide), CdTe (cadmium telluride), and ZnSe (zinc selenide) can be mentioned. The wafer preferably used in the present invention is a silicon wafer, and particularly preferably a mirror-polished silicon wafer having a size of 8 inches or more.

Examples of the metal include single element metals such as W, Mo, Pt, Fe, Ni and Au, alloys such as Inconel, Monel, mnemonic, carbon copper, Fe—Ni based Invar alloy and Super Invar alloy. Further, a multilayer metal plate formed by adding another metal layer or a ceramic layer to these metals is also included. In this case, if the overall coefficient of linear expansion (CTE) with the additional layer is low, Cu, Al, or the like is also used for the main metal layer. The metal used as the additional metal layer is limited as long as it has properties such as strong adhesion to the polymer film, no diffusion, and good chemical resistance and heat resistance. Although not, Cr, Ni, TiN, Mo-containing Cu and the like are preferable examples.

It is desirable that the flat portion of the inorganic substrate is sufficiently flat. Specifically, the PV value of the surface roughness is 50 nm or less, more preferably 20 nm or less, and further preferably 5 nm or less. If it is coarser than this, the peel strength between the polymer film layer and the inorganic substrate may be insufficient.
The thickness of the inorganic substrate is not particularly limited, but from the viewpoint of handleability, a thickness of 10 mm or less is preferable, 3 mm or less is more preferable, and 1.3 mm or less is further preferable. The lower limit of the thickness is not particularly limited, but is preferably 0.07 mm or more, more preferably 0.15 mm or more, and further preferably 0.3 mm or more.

The area of the inorganic substrate is preferably large from the viewpoint of production efficiency and cost of the polymer film laminated substrate and the flexible electronic device. Specifically, it is preferably 1000 cm2 or more, more preferably 1500 cm2 or more, and further preferably 2000 cm2 or more.

<Heat-resistant polymer film>
The heat-resistant polymer of the present invention is a polymer having a melting point of 400 ° C. or higher, preferably 500 ° C. or higher, and a glass transition temperature of 250 ° C. or higher, preferably 320 ° C. or higher, more preferably 380 ° C. or higher. Hereinafter, in order to avoid complication, the polymer is simply used. The melting point and the glass transition temperature in the present invention are determined by differential thermal analysis (DSC). When the melting point exceeds 500 ° C., it may be determined whether or not the melting point has been reached by visually observing the thermal deformation behavior when heated at the corresponding temperature.

The polymer film in the present invention includes aromatic polyimides such as polyimide, polyamideimide, polyetherimide, and fluorinated polyimide, polyimide resins such as alicyclic polyimide, polyethylene, polypropylene, polyethylene terephthalate, polybutylene terephthalate, and polyethylene-2. , Full aromatic polyester such as 6-naphthalate, copolymerized polyester such as semi-aromatic polyester, copolymerized (meth) acrylate represented by polymethylmethacrylate, polycarbonate, polyamide, polysulphon, polyethersulphon, polyetherketone, acetic acid Examples of films such as cellulose, cellulose nitrate, aromatic polyamide, polyimide chloride, polyphenol, polyarylate, polyphenylene sulfide, polyphenylene oxide, and polystyrene can be exemplified.
However, since it is a major premise that the present invention is used in a process involving a heat treatment of 450 ° C. or higher, the polymer films exemplified are limited to those that can be actually applied. The polymer film preferably used in the present invention is a film using a so-called super engineering plastic, preferably an aromatic polyimide film, an aromatic amide film, an ant, an aromatic amideimide film, and an aromatic benzoxazole. It is a film, an aromatic benzothiazole film, and an aromatic benzoimidazole film.

The details of the polyimide resin film will be described below. Generally, a polyimide-based resin film is a green film (hereinafter referred to as a green film) in which a polyamic acid (polyimide precursor) solution obtained by reacting diamines and tetracarboxylic acids in a solvent is applied to a support for producing a polyimide film and dried. It is also referred to as "polyamic acid film"), and is obtained by subjecting a green film to a high temperature heat treatment to carry out a dehydration ring closure reaction on a support for producing a polyimide film or in a state of being peeled off from the support.

The diamines constituting the polyamic acid are not particularly limited, and aromatic diamines, aliphatic diamines, alicyclic diamines and the like usually used for polyimide synthesis can be used. From the viewpoint of heat resistance, aromatic diamines are preferable, and among aromatic diamines, aromatic diamines having a benzoxazole structure are more preferable. When aromatic diamines having a benzoxazole structure are used, it is possible to develop high elastic modulus, low coefficient of thermal expansion, and low linear expansion coefficient as well as high heat resistance. The diamines may be used alone or in combination of two or more.

The aromatic diamines having a benzoxazole structure are not particularly limited, and are, for example, 5-amino-2- (p-aminophenyl) benzoxazole, 6-amino-2- (p-aminophenyl) benzoxazole, 5 -Amino-2- (m-aminophenyl) benzoxazole, 6-amino-2- (m-aminophenyl) benzoxazole, 2,2'-p-phenylenebis (5-aminobenzoxazole), 2,2' -P-Phenylenebis (6-aminobenzoxazole), 1- (5-aminobenzoxazole) -4- (6-aminobenzoxazolo) benzene, 2,6- (4,4'-diaminodiphenyl) benzo [1,2-d: 5,4-d'] bisoxazole, 2,6- (4,4-diaminodiphenyl) benzo [1,2-d: 4,5-d'] bisoxazole, 2, 6- (3,4'-diaminodiphenyl) benzo [1,2-d: 5,4-d'] bisoxazole, 2,6- (3,4'-diaminodiphenyl) benzo [1,2-d:: 4,5-d'] bisoxazole, 2,6- (3,3'-diaminodiphenyl) benzo [1,2-d: 5,4-d'] bisoxazole, 2,6- (3,3') -Diaminodiphenyl) benzo [1,2-d: 4,5-d'] bisoxazole and the like can be mentioned.

Examples of aromatic diamines other than the above-mentioned aromatic diamines having a benzoxazole structure include 2,2'-dimethyl-4,4'-diaminobiphenyl and 1,4-bis [2- (4-aminophenyl). ) -2-propyl] benzene (bisaniline), 1,4-bis (4-amino-2-trifluoromethylphenoxy) benzene, 2,2'-ditrifluoromethyl-4,4'-diaminobiphenyl, 4,4 '-Bis (4-aminophenoxy) biphenyl, 4,4'-bis (3-aminophenoxy) biphenyl, bis [4- (3-aminophenoxy) phenyl] ketone, bis [4- (3-aminophenoxy) phenyl ] Sulfates, bis [4- (3-aminophenoxy) phenyl] sulfone, 2,2-bis [4- (3-aminophenoxy) phenyl] propane, 2,2-bis [4- (3-aminophenoxy) phenyl ] -1,1,1,3,3,3-hexafluoropropane, m-phenylenediamine, o-phenylenediamine, p-phenylenediamine, m-aminobenzylamine, p-aminobenzylamine, 3,3'- Diaminodiphenyl ether, 3,4'-diaminodiphenyl ether, 4,4'-diaminodiphenyl ether, 3,3'-diaminodiphenyl sulfide, 3,3'-diaminodiphenyl sulfoxide, 3,4'-diaminodiphenyl sulfoxide, 4,4' −Diaminodiphenylsulfoxide, 3,3′-diaminodiphenylsulfone, 3,4′-diaminodiphenylsulfone, 4,4′-diaminodiphenylsulfone, 3,3′-diaminobenzophenone, 3,4′-diaminobenzophenone, 4, 4'-diaminobenzophenone, 3,3'-diaminodiphenylmethane, 3,4'-diaminodiphenylmethane, 4,4'-diaminodiphenylmethane,
Bis [4- (4-aminophenoxy) phenyl] methane, 1,1-bis [4- (4-aminophenoxy) phenyl] ethane, 1,2-bis [4- (4-aminophenoxy) phenyl] ethane, 1,1-bis [4- (4-aminophenoxy) phenyl] propane, 1,2-bis [4- (4-aminophenoxy) phenyl] propane, 1,3-bis [4- (4-aminophenoxy) Phenyl] propane, 2,2-bis [4- (4-aminophenoxy) phenyl] propane, 1,1-bis [4- (4-aminophenoxy) phenyl] butane, 1,3-bis [4- (4) -Aminophenoxy) phenyl] butane, 1,4-bis [4- (4-aminophenoxy) phenyl] butane, 2,2-bis [4- (4-aminophenoxy) phenyl] butane, 2,3-bis [ 4- (4-Aminophenoxy) phenyl] butane, 2- [4- (4-aminophenoxy) phenyl] -2- [4- (4-aminophenoxy) -3-methylphenyl] propane, 2,2-bis [4- (4-Aminophenoxy) -3-methylphenyl] propane, 2- [4- (4-aminophenoxy) phenyl] -2- [4- (4-aminophenoxy) -3,5-dimethylphenyl] Propane, 2,2-bis [4- (4-aminophenoxy) -3,5-dimethylphenyl] propane, 2,2-bis [4- (4-aminophenoxy) phenyl] -1,1,1,3 , 3,3-Hexafluoropropane, 1,4-bis (3-aminophenoxy) benzene, 1,3-bis (3-aminophenoxy) benzene, 1,4-bis (4-aminophenoxy) benzene, 4, 4'-bis (4-aminophenoxy) biphenyl, bis [4- (4-aminophenoxy) phenyl] ketone, bis [4- (4-aminophenoxy) phenyl] sulfide, bis [4- (4-aminophenoxy) Phenyl] sulfoxide, bis [4- (4-aminophenoxy) phenyl] sulfone, bis [4- (3-aminophenoxy) phenyl] ether, bis [4- (4-aminophenoxy) phenyl] ether, 1,3- Bis [4- (4-aminophenoxy) benzoyl] benzene, 1,3-bis [4- (3-aminophenoxy) benzoyl] benzene, 1,4-bis [4- (3-aminophenoxy) benzoyl] benzene, 4,4'-bis [(3-aminophenoxy) benzoyl] benzene, 1,1-bis [4- (3- (3- (3-) bis] Aminophenoxy) phenyl] propane, 1,3-bis [4- (3-aminophenoxy) phenyl] propane, 3,4'-diaminodiphenylsulfide, 2,2-bis [3- (3-aminophenoxy) phenyl] -1,1,1,3,3,3-hexafluoropropane, bis [4- (3-aminophenoxy) phenyl] methane, 1,1-bis [4- (3-aminophenoxy) phenyl] ethane, 1 , 2-bis [4- (3-aminophenoxy) phenyl] ethane, bis [4- (3-aminophenoxy) phenyl] sulfoxide, 4,4'-bis [3- (4-aminophenoxy) benzoyl] diphenyl ether, 4,4'-Bis [3- (3-aminophenoxy) benzoyl] diphenyl ether,
4,4'-bis [4- (4-amino-α, α-dimethylbenzyl) phenoxy] benzophenone, 4,4'-bis [4- (4-amino-α, α-dimethylbenzyl) phenoxy] diphenylsulfone , Bis [4- {4- (4-aminophenoxy) phenoxy} phenyl] sulfone, 1,4-bis [4- (4-aminophenoxy) phenoxy-α, α-dimethylbenzyl] benzene, 1,3-bis [4- (4-Aminophenoxy) phenoxy-α, α-dimethylbenzyl] benzene, 1,3-bis [4- (4-amino-6-trifluoromethylphenoxy) -α, α-dimethylbenzyl] benzene, 1,3-bis [4- (4-amino-6-fluorophenoxy) -α, α-dimethylbenzyl] benzene, 1,3-bis [4- (4-amino-6-methylphenoxy) -α, α -Dimethylbenzyl] benzene, 1,3-bis [4- (4-amino-6-cyanophenoxy) -α, α-dimethylbenzyl] benzene, 3,3'-diamino-4,4'-diphenoxybenzophenone, 4,4'-diamino-5,5'-diphenoxybenzophenone, 3,4'-diamino-4,5'-diphenoxybenzophenone, 3,3'-diamino-4-phenoxybenzophenone, 4,4'-diamino -5-phenoxybenzophenone, 3,4'-diamino-4-phenoxybenzophenone, 3,4'-diamino-5'-phenoxybenzophenone, 3,3'-diamino-4,4'-dibiphenoxybenzophenone, 4,4 '-Diamino-5,5'-dibiphenoxybenzophenone, 3,4'-diamino-4,5'-dibiphenoxybenzophenone, 3,3'-diamino-4-biphenoxybenzophenone, 4,4'-diamino-5 -Bifenoxybenzophenone, 3,4'-diamino-4-biphenoxybenzophenone, 3,4'-diamino-5'-biphenoxybenzophenone,
1,3-bis (3-amino-4-phenoxybenzoyl) benzene, 1,4-bis (3-amino-4-phenoxybenzoyl) benzene, 1,3-bis (4-amino-5-phenoxybenzoyl) benzene , 1,4-bis (4-amino-5-phenoxybenzoyl) benzene, 1,3-bis (3-amino-4-biphenoxybenzoyl) benzene, 1,4-bis (3-amino-4-biphenoxy) Benzene) benzene, 1,3-bis (4-amino-5-biphenoxybenzoyl) benzene, 1,4-bis (4-amino-5-biphenoxybenzoyl) benzene, 2,6-bis [4- (4) -Amino-α, α-dimethylbenzyl) Phenoxy] Benzene, and some or all of the hydrogen atoms on the aromatic ring of the aromatic diamine are halogen atoms, alkyl or alkoxyl groups having 1 to 3 carbon atoms, and cyano. Examples thereof include aromatic diamines in which a part or all of hydrogen atoms of a group, an alkyl group or an alkoxyl group are substituted with a halogen atom and an alkyl halide group having 1 to 3 carbon atoms or an alkoxyl group is substituted.

Examples of the aliphatic diamines include 1,2-diaminoethane, 1,4-diaminobutane, 1,5-diaminopentane, 1,6-diaminohexane, 1,8-diaminooctane and the like.
Examples of the alicyclic diamines include 1,4-diaminocyclohexane and 4,4'-methylenebis (2,6-dimethylcyclohexylamine).
The total amount of diamines other than aromatic diamines (aliphatic diamines and alicyclic diamines) is preferably 20% by mass or less, more preferably 10% by mass or less, still more preferably 5% by mass or less of all diamines. Is. In other words, the aromatic diamines are preferably 80% by mass or more, more preferably 90% by mass or more, and further preferably 95% by mass or more of all diamines.

Examples of the tetracarboxylic acids constituting the polyamic acid include aromatic tetracarboxylic acids (including the acid anhydride thereof), aliphatic tetracarboxylic acids (including the acid anhydride), and alicyclic tetracarboxylic acids usually used for polyimide synthesis. Acids (including its acid anhydride) can be used. Among them, aromatic tetracarboxylic dianhydrides and alicyclic tetracarboxylic dianhydrides are preferable, aromatic tetracarboxylic dianhydrides are more preferable from the viewpoint of heat resistance, and alicyclics are more preferable from the viewpoint of light transmission. Group tetracarboxylic acids are more preferred. When these are acid anhydrides, the number of anhydride structures in the molecule may be one or two, but those having two anhydride structures (dianhydride) are preferable. Good. The tetracarboxylic acids may be used alone or in combination of two or more.

Examples of the alicyclic tetracarboxylic dians include cyclobutanetetracarboxylic dians, 1,2,4,5-cyclohexanetetracarboxylic dians, 3,3', 4,4'-bicyclohexyltetracarboxylic dians and the like. Examples include carboxylic acids and their acid anhydrides. Among these, dianhydrides having two anhydride structures (eg, cyclobutanetetracarboxylic dianhydride, 1,2,4,5-cyclohexanetetracarboxylic dianhydride, 3,3', 4,4 '-Bicyclohexyltetracarboxylic dianhydride, etc.) is suitable. The alicyclic tetracarboxylic acids may be used alone or in combination of two or more.
When transparency is important, the alicyclic tetracarboxylic acids are, for example, preferably 80% by mass or more, more preferably 90% by mass or more, and further preferably 95% by mass or more of all tetracarboxylic acids.

The aromatic tetracarboxylic acids are not particularly limited, but are preferably pyromellitic acid residues (that is, those having a structure derived from pyromellitic acid), and more preferably an acid anhydride thereof. Examples of such aromatic tetracarboxylic dianhydrides include pyromellitic dianhydride, 3,3', 4,4'-biphenyltetracarboxylic dianhydride, 4,4'-oxydiphthalic acid dianhydride, and 3 , 3', 4,4'-benzophenonetetracarboxylic dianhydride, 3,3', 4,4'-diphenylsulfonetetracarboxylic dianhydride, 2,2-bis [4- (3,4-di) Carboxylic phenoxy) phenyl] propanoic anhydride and the like can be mentioned.
When heat resistance is important, the aromatic tetracarboxylic acids are, for example, preferably 80% by mass or more, more preferably 90% by mass or more, and further preferably 95% by mass or more of all tetracarboxylic acids.

The application of the polymer solution or the polymer precursor solution on the silane coupling agent layer is, for example, spin coating, doctor blade, applicator, comma coater, screen printing method, slit coating, reverse coating, dip coating, curtain coating. , Slit die coat and other conventionally known solution coating means can be appropriately used.
For example, in a polyimide resin film, a polyamic acid (polyimide precursor) solution obtained by reacting diamines and tetracarboxylic acids in a solvent is applied to an inorganic substrate to a predetermined thickness, dried, and then dried. It can be obtained by performing a thermal imidization method in which a dehydration ring closure reaction is carried out by high-temperature heat treatment, or a chemical imidization method using acetic anhydride or the like as a dehydrating agent and pyridine or the like as a catalyst.

The thickness of the polymer film of the present invention is preferably 3 μm or more, more preferably 11 μm or more, still more preferably 24 μm or more, and even more preferably 45 μm or more. The upper limit of the thickness of the polymer film is not particularly limited, but it is preferably 250 μm or less, more preferably 150 μm or less, and further preferably 90 μm or less for use as a flexible electronic device.

The average CTE of the polymer film of the present invention between 30 ° C. and 500 ° C. is preferably −5 ppm / ° C. to + 20 ppm / ° C., more preferably −5 ppm / ° C. to + 15 ppm / ° C., and even more preferably. Is 1 ppm / ° C to + 10 ppm / ° C. When the CTE is within the above range, the difference in the coefficient of linear expansion from that of a general support (inorganic substrate) can be kept small, and the polymer film and the inorganic substrate are peeled off even when subjected to a heat application process. It can be avoided. Here, CTE is a factor representing reversible expansion and contraction with respect to temperature.

The thermal shrinkage of the polymer film of the present invention between 30 ° C. and 500 ° C. is preferably ± 0.9%, more preferably ± 0.6%. The heat shrinkage rate in the present invention is a factor representing irreversible expansion and contraction with respect to temperature.

The tensile breaking strength of the polymer film in the present invention is preferably 60 MPa or more, more preferably 120 MPa or more, and further preferably 240 MPa or more. The upper limit of the tensile breaking strength is not particularly limited, but is practically less than about 1000 MPa. The tensile breaking strength of the polymer film refers to the average value of the tensile breaking strength in the flow direction (MD direction) and the tensile breaking strength in the width direction (TD direction) of the polymer film.

The thickness unevenness of the polymer film in the present invention is preferably 20% or less, more preferably 12% or less, still more preferably 7% or less, and particularly preferably 4% or less. If the thickness spots exceed 20%, it tends to be difficult to apply to narrow areas. The thickness unevenness of the film can be obtained, for example, by randomly extracting about 10 positions from the film to be measured with a contact-type film thickness meter and measuring the film thickness based on the following formula.
Film thickness spots (%)
= 100 x (maximum film thickness-minimum film thickness) ÷ average film thickness

The polymer film in the present invention is preferably obtained in the form of being wound as a long polymer film having a width of 300 mm or more and a length of 10 m or more at the time of its manufacture, and is a roll wound around a winding core. The one in the form of a polymer film is more preferable.

In the polymer film, in order to ensure handleability and productivity, a lubricant (particle) having a particle size of about 10 to 1000 nm is added / contained in the polymer film in an amount of about 0.03 to 3% by mass. , It is preferable to impart fine irregularities to the surface of the polymer film to ensure slipperiness.

<Surface activation treatment of polymer film>
It is preferable that the polymer film used in the present invention is subjected to a surface activation treatment. By performing the surface activation treatment on the polymer film, the surface of the polymer film is modified to a state in which functional groups are present (so-called activated state), and the adhesiveness to the inorganic substrate is improved.
The surface activation treatment in the present invention is a dry or wet surface treatment. Examples of the dry surface treatment include vacuum plasma treatment, atmospheric pressure plasma treatment, treatment of irradiating the surface with active energy rays such as ultraviolet rays, electron beams, and X-rays, corona treatment, flame treatment, and itro treatment. it can. Examples of the wet surface treatment include a treatment in which the surface of the polymer film is brought into contact with an acid or alkaline solution.

In the present invention, a plurality of surface activation treatments may be combined. Such surface activation treatment cleans the surface of the polymer film and produces more active functional groups. The generated functional groups are bound to the silane coupling agent layer by hydrogen bonds, chemical reactions, etc., and the polymer film layer and the silane coupling agent layer can be firmly adhered to each other.

In the present invention, the silane coupling agent means a compound that physically or chemically intervenes between the inorganic substrate and the polymer film layer and has an action of enhancing the adhesive force between the two.
The coupling agent is not particularly limited, but a silane coupling agent having an amino group or an epoxy group is preferable. Preferred specific examples of the silane coupling agent include N-2- (aminoethyl) -3-aminopropylmethyldimethoxysilane, N-2- (aminoethyl) -3-aminopropyltrimethoxysilane, and N-2- ( Aminoethyl) -3-aminopropyltriethoxysilane, 3-aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, 3-triethoxysilyl-N- (1,3-dimethyl-butylidene) propylamine, 2- (3,4-Epoxycyclohexyl) Ethyltrimethoxysilane, 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropylmethyldiethoxysilane, 3-glycidoxypropyltriethoxysilane, vinyltricrolsilane, Vinyl trimethoxysilane, vinyl triethoxysilane, 2- (3,4-epoxycyclohexyl) ethyltrimethoxysilane, 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropylmethyldiethoxysilane, 3-glycid Xypropyltriethoxysilane, p-styryltrimethoxysilane, 3-methacryloxypropylmethyldimethoxysilane, 3-methacryloxypropyltrimethoxysilane, 3-methacryloxypropylmethyldiethoxysilane, 3-methacryloxypropyltriethoxysilane, 3-Acryloxypropyltrimethoxysilane, N-phenyl-3-aminopropyltrimethoxysilane, N- (vinylbenzyl) -2-aminoethyl-3-aminopropyltrimethoxysilane hydrochloride, 3-ureidopropyltriethoxysilane , 3-Chloropropyltrimethoxysilane, 3-mercaptopropylmethyldimethoxysilane, 3-mercaptopropyltrimethoxysilane, bis (triethoxysilylpropyl) tetrasulfide, 3-isocyanuppropyltriethoxysilane, tris- (3-trimethoxy) Cyrilpropyl) isocyanurate, chloromethylphenetyltrimethoxysilane, chloromethyltrimethoxysilane, aminophenyltrimethoxysilane, aminophenyltrimethoxysilane, aminophenylaminomethylphenetyltrimethoxysilane and the like.

In addition to the above, silane coupling agents that can be used in the present invention include n-propyltrimethoxysilane, butyltrichlorosilane, 2-cyanoethyltriethoxysilane, cyclohexyltrichlorosilane, decyltrichlorosilane, and diacetoxydimethylsilane. Diethoxydimethylsilane, dimethoxydimethylsilane, dimethoxydiphenylsilane, dimethoxymethylphenylsilane, dodecyllichlorosilane, dodecyltrimethoxylane, ethyltrichlorosilane, hexyltrimethoxysilane, octadecyltriethoxysilane, octadecyltrimethoxysilane, n-octyltri Chlorosilane, n-octyltriethoxysilane, n-octyltrimethoxysilane, triethoxyethylsilane, triethoxymethylsilane, trimethoxymethylsilane, trimethoxyphenylsilane, pentylliethoxysilane, pentyltrichlorosilane, triacetoxymethylsilane, Trichlorohexylsilane, trichloromethylsilane, trichlorooctadecylsilane, trichloropropylsilane, trichlorotetradecylsilane, trimethoxypropylsilane, allyltrichlorosilane, allyltriethoxysilane, allyltrimethoxysilane, diethoxymethylvinylsilane, dimethoxymethylvinylsilane, trichloro Vinylsilane, triethoxyvinylsilane, vinyltris (2-methoxyethoxy) silane, trichloro-2-cyanoethylsilane, diethoxy (3-glycidyloxypropyl) methylsilane, 3-glycidyloxypropyl (dimethoxy) methylsilane, 3-glycidyloxypropyltrimethoxysilane Etc. can also be used.

In the present invention, a silane coupling agent having one silicon atom in one molecule is particularly preferable, for example, N-2- (aminoethyl) -3-aminopropylmethyldimethoxysilane, N-2- (aminoethyl). ) -3-Aminopropyltrimethoxysilane, N-2- (aminoethyl) -3-aminopropyltriethoxysilane, 3-aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, 3-triethoxysilyl-N -(1,3-Dimethyl-butylidene) propylamine, 2- (3,4-epoxycyclohexyl) ethyltrimethoxysilane, 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropylmethyldiethoxysilane , 3-Glycydoxypropyltriethoxysilane, aminophenyltrimethoxysilane, aminophenyl trimethoxysilane, aminophenyl aminomethylphenyl trimethoxysilane, and the like. When particularly high heat resistance is required in the process, it is desirable to connect Si and an amino group with an aromatic group.
As the coupling agent that can be used in the present invention, a coupling agent other than the above-mentioned silane coupling agent can also be used, for example, 1-mercapto-2-propanol, 3-mercaptopropionate methyl, 3-mercapto. -2-butanol, butyl 3-mercaptopropionate, 3- (dimethoxymethylsilyl) -1-propanethiol, 4- (6-mercaptohexaloyl) benzyl alcohol, 11-amino-1-undecenothiol, 11-mercapto Undecylphosphonic acid, 11-mercaptoundecyltrifluoroacetic acid, 2,2'-(ethylenedioxy) dietanthiol, 11-mercaptoundecyltri (ethylene glycol), (1-mercaptoundic-11-yl) Tetra (ethylene glycol), 1- (methylcarboxy) undec-11-yl) hexa (ethylene glycol), hydroxyundesyl disulfide, carboxyundecyl disulfide, hydroxyhexadodecyl disulfide, carboxyhexadecyl disulfide, tetrakis (2-ethylhexyloxy) ) Titanium, titanium dioctyloxybis (octylene glycolate), zirconium tributoxymonoacetylacetonate, zirconium monobutoxyacetylacetonatebis (ethylacetacetate), zirconium tributoxymonostearate, acetoalkoxyaluminum diisopropyrate, 3-Glysidyloxypropyltrimethoxysilane, 2,3-butanedithiol, 1-butanethiol, 2-butanethiol, cyclohexanethiol, cyclopentanethiol, 1-decanethiol, 1-dodecanethiol, 3-mercaptopropionic acid-2 -Ethylhexyl, ethyl 3-mercaptopropionate, 1-heptanethiol, 1-hexadecanethiol, hexyl mercaptan, isoamyl mercaptan, isobutyl mercaptan, 3-mercaptopropionic acid, 3-mercaptopropionic acid-3-methoxybutyl, 2-methyl- 1-butane thiol, 1-octadecane thiol, 1-octane thiol, 1-pentadecane thiol, 1-pentane thiol, 1-propane thiol, 1-tetradecane thiol, 1-undecane thiol, 1- (12-mercaptododecyl) imidazole, 1- (11-mercaptoundesyl) imidazole, 1- (10-mercaptodecyl) Imidazole, 1- (16-mercaptohexadecyl) imidazole, 1- (17-mercaptoheptadecyl) imidazole, 1- (15-mercapto) dodecanoic acid, 1- (11-mercapto) undecanoic acid, 1- (10-mercapto) ) Decanoic acid and the like can also be used.

<Method of forming a silane coupling agent layer>
As a method for forming the silane coupling agent layer, a method of applying a silane coupling agent solution, a vapor deposition method, or the like can be used. The silane coupling agent layer may be applied to either the surface of the polymer film or the inorganic substrate, or may be applied to both surfaces. When a thin film layer is separately formed on the inorganic substrate, it may be formed on the thin film layer.
As a method of applying the silane coupling agent solution, a spin coating method, a curtain coating method, a dip coating method, a slit die coating method, a gravure coating method, a bar, using a solution obtained by diluting the silane coupling agent with a solvent such as alcohol. Conventionally known solution coating means such as a coating method, a comma coating method, an applicator method, a screen printing method, and a spray coating method can be appropriately used. When the method of applying the silane coupling agent solution is used, it is preferable that the solution is quickly dried after the application and further heat-treated at about 100 ± 30 ° C. for about several tens of seconds to 10 minutes. By the heat treatment, the silane coupling agent and the surface of the surface to be coated are bonded by a chemical reaction.

Further, the silane coupling agent layer can be formed by a vapor deposition method, and specifically, the base material is formed by exposing the base material to the vapor of the silane coupling agent, that is, the silane coupling agent in a substantially gaseous state. The vapor of the silane coupling agent can be obtained by heating the liquid silane coupling agent to a temperature from 40 ° C. to about the boiling point of the silane coupling agent. The boiling point of the silane coupling agent varies depending on the chemical structure, but is generally in the range of 100 to 250 ° C. However, heating at 200 ° C. or higher is not preferable because it may cause a side reaction on the organic group side of the silane coupling agent.
The environment for heating the silane coupling agent may be any of pressure, normal pressure, and reduced pressure, but in the case of promoting vaporization of the silane coupling agent, normal pressure or reduced pressure is preferable. Since many silane coupling agents are flammable liquids, it is preferable to carry out the vaporization work in a closed container, preferably after replacing the inside of the container with an inert gas.
The time for exposing the substrate to the silane coupling agent is not particularly limited, but is preferably 20 hours or less, more preferably 60 minutes or less, still more preferably 15 minutes or less, and most preferably 1 minute or less.
The temperature of the base material during exposure of the base material to the silane coupling agent is controlled to an appropriate temperature between -50 ° C and 200 ° C depending on the type of the silane coupling agent and the desired thickness of the silane coupling agent layer. It is preferable to do so.
The substrate exposed to the silane coupling agent is preferably heated to 70 ° C. to 200 ° C., more preferably 75 ° C. to 150 ° C. after exposure. By such heating, the hydroxyl group on the surface of the base material reacts with the alkoxy group or the silazane group of the silane coupling agent, and the silane coupling agent treatment is completed. The time required for heating is 10 seconds or more and 10 minutes or less. If the heating temperature after exposure is too high or the heating time after exposure is too long, the silane coupling agent may deteriorate. Further, if the heating time after exposure is too short, the treatment effect cannot be obtained. If the substrate temperature during exposure to the silane coupling agent is already 80 ° C. or higher, heating after exposure can be omitted.
In the present invention, it is preferable to use a thin-film deposition method to hold the surface of the base material on which the silane coupling agent layer is to be formed downward and expose it to the silane coupling agent vapor. In the method of applying the silane coupling agent solution, the coated surface of the base material inevitably faces upward during and before and after the coating, so it cannot be denied that suspended foreign matter in the working environment may be deposited on the surface of the base material. .. However, in the thin-film deposition method, the surface on which the silane coupling agent layer of the base material is to be formed can be held downward, so that foreign substances in the environment can be applied to the surface of the base material (or the surface of the thin film) or the surface of the silane coupling agent layer. It is less likely to adhere.
It is preferable to clean the surface of the base material before the treatment with the silane coupling agent by means such as short wavelength UV / ozone irradiation or with a liquid cleaning agent.

The film thickness of the silane coupling agent layer is extremely thin compared to the base material, polymer film, etc., and is negligible from the viewpoint of mechanical design. A thickness on the order of the molecular layer is sufficient. Generally, it is less than 400 nm, preferably 200 nm or less, more preferably 100 nm or less, more preferably 50 nm or less, still more preferably 10 nm or less in practical use. However, in the calculated region of 5 nm or less, the silane coupling agent layer may exist in a cluster form rather than as a uniform coating film. The film thickness of the silane coupling agent layer can be obtained by ellipsometry or by calculating from the concentration of the silane coupling agent solution at the time of coating and the coating amount.

<Thin film>
In the present invention, at least one metal thin film selected from molybdenum, tungsten, and chromium is continuously or discontinuously formed on at least a part of one side of the inorganic plate between the silane coupling agent layer and the inorganic substrate. Is preferable. The following examples will be described on the premise that the polymer film is attached only to one side of the inorganic substrate, but the form in which the polymer film is attached to both sides of the inorganic substrate is also within the scope of the present invention.

What is used as a single metal thin film in the present invention is a thin film of at least one metal selected from molybdenum and tungsten. In the present invention, when each single metal thin film is used, it is preferable to use a metal thin film having at least the outermost surface having a purity of 85% or more, preferably 92% or more, and more preferably 98% or more. Also, as an exception, an alloy composed of molybdenum and tungsten can be used. In this case, the alloy ratio of molybdenum and tungsten can be widely used from molybdenum: tungsten = 1:99 to 99: 1 (elemental ratio).
The thickness of the thin film is preferably 3 nm or more and 5 μm or less, more preferably 12 nm or more and 3 μm or less, and further preferably 36 nm or more and 1.2 μm or less.

The method for forming the thin film is not particularly limited, and known thin film forming means such as thin film deposition, sputtering, reactive sputtering, ion beam sputtering, and CVD can be used depending on the type and characteristics of the film forming source.
In the present invention, the non-conductor layer on the surface can be strengthened by oxygen plasma treatment, anodization treatment, atmospheric pressure plasma treatment, or the like after forming the metal thin film.

As another preferred embodiment of the present invention, a form in which a thin film layer of aluminum oxide is inserted between the silane coupling agent layer and the inorganic substrate can be exemplified. It is preferable that the thin film layer of the aluminum oxide is continuously or discontinuously formed on at least a part of one surface of the inorganic plate. In the present invention, it is preferable to use an aluminum oxide having at least the outermost surface having a purity of 85% or more, preferably a purity of 92% or more, and more preferably a purity of 98% or more. The thickness of the thin film is preferably 3 nm or more and 5 μm or less, more preferably 12 nm or more and 3 μm or less, and further preferably 36 nm or more and 1.2 μm or less.

As another preferred embodiment of the present invention, a form in which a thin film layer of aluminum nitride is inserted between the silane coupling agent layer and the inorganic substrate can be exemplified. It is preferable that the thin film layer of the aluminum nitride is continuously or discontinuously formed on at least a part of one surface of the inorganic plate. In the present invention, it is preferable to use an aluminum nitride having at least the outermost surface having a purity of 85% or more, preferably a purity of 92% or more, and more preferably a purity of 98% or more. The thickness of the thin film is preferably 3 nm or more and 5 μm or less, more preferably 12 nm or more and 3 μm or less, and further preferably 36 nm or more and 1.2 μm or less.

As another preferred embodiment of the present invention, a form in which a thin film of a silicon compound is inserted between the silane coupling agent layer and the inorganic substrate can be exemplified. It is preferable that the thin film layer of the silicon compound is continuously or discontinuously formed on at least a part of one surface of the inorganic plate. Preferred silicon compounds in the present invention are silicon nitride and silicon oxide. The thickness of the thin film is preferably 3 nm or more and 5 μm or less, more preferably 12 nm or more and 3 μm or less, and further preferably 36 nm or more and 1.2 μm or less. The silicon nitride thin film can be formed by using a CVD method, a reactive sputtering method, or the like. Further, as the silicon oxide thin film, a vapor deposition method, a reactive sputtering method, a method of oxidizing the silicon thin film by post-treatment, or the like can be used.

As another preferred embodiment of the present invention, a form in which a thin film of a composite oxide of aluminum and silicon is inserted between the silane coupling agent layer and the inorganic substrate can be exemplified. It is preferable that the thin film layer of the composite oxide of aluminum and silicon (silicon) is continuously or discontinuously formed on at least a part of one surface of the inorganic plate. The preferred ratio of aluminum to silicon in the thin film of the present invention is aluminum / silicon = 90/10 to 30/70 (elemental ratio), preferably 90/10 to 50/50. If the silicon ratio exceeds this range, the interaction with the silane coupling agent becomes too strong, which may hinder peeling. The thickness of the thin film is preferably 3 nm or more and 5 μm or less, more preferably 12 nm or more and 3 μm or less, and further preferably 36 nm or more and 1.2 μm or less.

The method for forming the thin film is not particularly limited, and known thin film forming means such as thin film deposition, sputtering, reactive sputtering, ion beam sputtering, and CVD can be used depending on the type and characteristics of the film forming source. In the present invention, a method of oxidizing aluminum by oxygen plasma treatment, anodization treatment, atmospheric pressure plasma treatment, etc. after forming a metallic aluminum or metallic silicon thin film, a method of depositing a composite oxide thin film using reactive sputtering, and reactivity. An example of a method using the ion cluster method can be exemplified. It is also possible to use reactive sputtering of metallic aluminum and vapor deposition or sputtering of silicon oxide in combination.

In the thin film layer inserted between the silane coupling agent layer and the inorganic substrate in the present invention, each of the above-exemplified thin film layers can be inserted individually or in a plurality of layers. In the present invention, at least one metal thin film selected from molybdenum, tungsten, chromium, and nickel-chromium alloy is formed on an inorganic substrate, followed by a thin film layer of aluminum oxide, a thin film layer of aluminum nitride, and a thin film of silicon compound. It is preferable to insert a multilayer thin film layer having formed a layer, at least one thin film layer selected from a composite oxide thin film layer of aluminum and silicon. That is, the preferred layer structure in the present invention is
Polymer film layer / silane coupling agent layer / oxide layer / metal layer / inorganic substrate,
Polymer film layer / silane coupling agent layer / nitride layer / metal layer / inorganic substrate,
Is. Here, the oxide layer is one or more thin film layers selected from a thin film layer of aluminum oxide, a thin film layer of silicon oxide, and a composite oxide thin film layer of aluminum and silicon, and the nitride layer is a thin film layer of aluminum nitride. , One or more thin film layers selected from silicon nitride thin film layers, and the metal layer is one or more metal thin films selected from molybdenum, tungsten, chromium, nickel-chromium alloys, or alloy thin film layers thereof. When a nickel-chromium alloy is used, the preferred alloy composition is nickel / chromium = 75/25 to 10/90 (element ratio).

<Pressurized heat treatment>
The laminate of the present invention is produced by superimposing an inorganic substrate provided with a silane coupling agent layer and the polymer film and heat-treating under pressure.

The pressure heat treatment may be performed, for example, in an atmospheric pressure atmosphere or in a vacuum while heating a press, a laminate, a roll laminate, or the like. In addition, a method of pressurizing and heating in a flexible bag can also be applied. From the viewpoint of improving productivity and reducing the processing cost brought about by high productivity, pressing or roll laminating in an atmospheric atmosphere is preferable, and a method using rolls (roll laminating or the like) is particularly preferable.

The pressure during the pressure heat treatment is preferably 1 MPa to 20 MPa, more preferably 3 MPa to 10 MPa. If the pressure is too high, the inorganic substrate may be damaged, and if the pressure is too low, there may be a portion that does not adhere to the substrate, resulting in insufficient adhesion. The temperature during the pressure heat treatment is 150 ° C. to 400 ° C., more preferably 250 ° C. to 350 ° C. When the polymer film is a polyimide film, if the temperature is too high, the polyimide film may be damaged, and if the temperature is too low, the adhesion tends to be weakened.
Further, the pressure heat treatment can be performed in an atmospheric pressure atmosphere as described above, but it is preferable to perform the pressure heat treatment in a vacuum in order to obtain a stable peel strength on the entire surface. At this time, the degree of vacuum is sufficient with the degree of vacuum by a normal oil rotary pump, and about 10 Torr or less is sufficient.
As a device that can be used for pressure heat treatment, for example, "11FD" manufactured by Imoto Seisakusho can be used for pressing in a vacuum, and a roll-type film laminator in a vacuum or a vacuum is used. For vacuum laminating such as a film laminator that applies pressure to the entire surface of the glass at once with a thin rubber film, for example, "MVLP" manufactured by Meiki Co., Ltd. can be used.

The pressurization heat treatment can be performed separately for the pressurization process and the heating process. In this case, first, the polymer film and the inorganic substrate are pressurized (preferably about 0.2 to 50 MPa) at a relatively low temperature (for example, less than 120 ° C., more preferably 95 ° C. or lower) to ensure close contact between the two. Then, at a low pressure (preferably less than 0.2 MPa, more preferably 0.1 MPa or less) or a normal pressure at a relatively high temperature (for example, 120 ° C. or higher, more preferably 120 to 250 ° C., still more preferably 150 to 230 ° C.). ), The chemical reaction at the close contact interface is promoted, and the polymer film and the inorganic substrate can be laminated.

From the above, the laminate of the following (1) or (2) in the present invention can be obtained.
(1)
It is a laminate of a heat-resistant polymer film and an inorganic substrate, and the initial peel strength between the heat-resistant polymer film and the inorganic substrate and the peel strength when cooled to room temperature after heat treatment at 450 ° C in a nitrogen environment are as follows. A laminate characterized by satisfying the relational expression.
0.05 ≤ F0 ≤ 3.00
dFt = (Ft−F0) / t
−0.15 ≦ dFt ≦ + 0.15
0.02 ≤ Ft
Here, F0 [N / cm]: Initial peel strength t [hr]: Heat treatment time in a nitrogen environment at 450 ° C. An integer in the range of 1 to 3 Ft [N / cm]: Peel strength after heat treatment t hours ( 2)
It is a laminate of a heat-resistant polymer film and an inorganic substrate, and the initial peel strength between the heat-resistant polymer film and the inorganic substrate and the peel strength when cooled to room temperature after heat treatment at 510 ° C. in a nitrogen environment are as follows. A laminate characterized by satisfying the relational expression.
0.05 ≤ F0 ≤ 3.00
dFs = (Fs−F0) / s
−0.15 ≦ dFs ≦ + 0.15
0.02 ≤ Fs
Here, F0 [N / cm]: Initial peel strength s [hr]: Heat treatment time in a nitrogen environment at 510 ° C. An integer in the range of 1 to 3 Fs [N / cm]: Peel strength after heat treatment s hours

In the present invention, the above (1) and (2) may be satisfied independently or compatible with each other. Further, in the present invention, preferably, the following (3) may be independently or compatible with one or both of (1) and (2).
(3)
It is a laminate of a heat-resistant polymer film and an inorganic substrate, and the initial peel strength between the heat-resistant polymer film and the inorganic substrate and the peel strength when cooled to room temperature after heat treatment at 530 ° C. in a nitrogen environment are as follows. A laminate characterized by satisfying the relational expression.
0.05 ≤ F0 ≤ 3.00
dFu = (Fu−F0) / u
−0.15 ≦ dFu ≦ + 0.15
0.02 ≤ Fu
Here, F0 [N / cm]: Initial peel strength
u [hr]: Heat treatment time at 530 ° C. in a nitrogen environment An integer in the range of 1 to 3 Fu [N / cm]: Peeling strength after heat treatment u hours

In the present invention, by forming the portion forming the thin film layer of the present invention by dividing it in a pattern, the polymer film is a region that can be easily separated from the inorganic substrate, which is a region that cannot be easily separated from the easily peeled portion. A good adhesive portion can be formed. When the patterning is performed in this way, the easily peelable portion can be easily peeled off from the substrate by making a cut along the edge of the pattern from the surface on which the polymer films are laminated. That is, the portion satisfying the requirements of the present invention is the easily peelable portion.

<Thin film patterning>
As a means for patterning the thin film layer, a general masking method, an etching method using a resist after forming a thin film on the front surface, a lift-off method, or the like can be used. The pattern shape may be appropriately set according to the type of the device to be laminated and the like, and is not particularly limited, and the pattern may be a pattern in which the required device shape is tiling independently or in a multi-faceted manner on a plane.

The peel strength between the inorganic substrate and the polymer film in the good adhesive portion is twice or more, preferably 3 times or more, more preferably 5 times the peel strength between the inorganic substrate and the polymer film in the easy peeling portion. More than double. Further, the strength ratio is preferably a multiple of the above and 100 times or less, and more preferably 50 times or less. The method for measuring the peel strength will be described later.
When the peeling strength between the inorganic substrate and the polymer film in the good adhesive portion is less than twice the peeling strength between the inorganic substrate and the polymer film in the easy peeling portion, when the polymer film is peeled from the inorganic substrate, It becomes difficult to peel off the device forming portion with low stress by utilizing the difference in peeling strength between the good adhesive portion and the easy peeling portion, which may reduce the yield of the flexible electronic device. On the contrary, if the difference in peel strength between the good adhesive part and the easy-peelable part is too large, the easy-peelable part may be peeled from the inorganic substrate, or the easy-peeling part may be fluffy or blisters (swelling of the coating film). In some cases.
The peel strength of the good adhesive portion is preferably 0.8 N / cm or more, more preferably 1.5 N / cm or more, further preferably 2.4 N / cm or more, and most preferably 3.2 N / cm or more. ..

In the present invention, it is preferable that the peel strength of the easily peeled portion described above is maintained at a sufficiently low state even after heat treatment at 500 ° C. for 10 minutes. By satisfying such conditions, good peelability can be maintained even when a high temperature of 420 ° C. or higher, preferably 460 ° C. or higher, more preferably 510 ° C. or higher is used in the actual processing process.

<Manufacturing method of flexible electronic device>
When the laminate of the present invention is used, an electronic device is formed on the polymer film of the laminate using existing equipment and processes for manufacturing electronic devices, and the polymer film is peeled off from the laminate to be flexible. Electronic devices can be made.
The electronic device in the present invention refers to a wiring substrate having a single-sided, double-sided, or multi-layered structure for electrical wiring, an active element such as a transistor or a diode, an electronic circuit including a passive device such as a resistor, a capacitor, or an inductor, and other pressures. , Sensor element that senses temperature, light, humidity, etc., biosensor element, light emitting element, liquid crystal display, electrophoresis display, self-luminous display and other image display elements, wireless and wired communication elements, arithmetic elements, storage elements, MEMS Refers to elements, solar cells, thin films, etc.

In the method for producing a device structure of the present invention, after the device is formed on the polymer film of the laminate produced by the above method, a cut is made in the polymer film of the easily peelable portion of the laminate. The polymer film is peeled off from the inorganic substrate.
As a method of making a cut in the polymer film of the easily peelable portion of the laminated body, a method of cutting the polymer film with a cutting tool such as a cutting tool or a method of relatively scanning the polymer film with a laser to scan the polymer film. There are a method of cutting, a method of cutting a polymer film by relatively scanning a water jet and a laminate, and a method of cutting a polymer film while cutting a little to the glass layer with a dying device of a semiconductor chip. The method is not limited. For example, in adopting the above-mentioned method, it is also possible to appropriately adopt a method such as superimposing ultrasonic waves on the cutting tool or adding a reciprocating motion or a vertical motion to improve the cutting performance.

The method of peeling the polymer film with the device from the inorganic substrate is not particularly limited, but the method of winding from the edge with a tweezers or the like, or the tape portion after attaching the adhesive tape to one side of the notched portion of the polymer film. A method of winding from the surface, a method of vacuum-adsorbing one side of the cut portion of the polymer film and then winding from that portion, and the like can be adopted. If the notched portion of the polymer film is bent with a small curvature during peeling, stress will be applied to the device at that portion and the device may be destroyed. Therefore, peel it off with the curvature as large as possible. Is desirable. For example, it is desirable to wind it while winding it on a roll having a large curvature, or to use a machine having a structure in which the roll having a large curvature is located at the peeling portion.
It is also useful to attach another reinforcing base material to the part to be peeled off in advance and peel off the entire reinforcing base material. When the flexible electronic device to be peeled off is the backplane of the display device, it is also possible to attach the frontplane of the display device in advance, integrate it on an inorganic substrate, and then peel off both at the same time to obtain a flexible display device. is there.

<Recycling of inorganic substrates>
In the polymer film laminated substrate of the present invention, after the electronic device is peeled off, the residual polymer film is completely removed from the polymer film laminated substrate, and a simple cleaning treatment or the like is performed to reuse the inorganic substrate. can do. This is because the adhesive force between the thin film and the silane coupling agent layer in the easy peeling portion is uniform and stable, and the polymer film layer can be peeled off smoothly, so that almost no peeling residue remains on the inorganic substrate side. according to. It is considered that this is because the peeled surface when peeling the polymer film becomes the thin film surface (the interface between the thin film and the silane coupling agent layer). Therefore, after the polymer film is peeled off, the state in which a thin film is formed on the inorganic substrate (hereinafter, the inorganic substrate in this state is referred to as a thin film laminated inorganic substrate) is maintained.

Hereinafter, the present invention will be described in more detail with reference to Examples, but the present invention is not limited to the following Examples, and is appropriately modified and carried out within a range that can be adapted to the gist of the above and the following. It is also possible, all of which are within the technical scope of the invention.
The evaluation method of the physical properties in the following examples is as follows.

<Reduced viscosity of polyamic acid solution>
The solution dissolved in N, N-dimethylacetamide so that the polymer concentration was 0.2 g / dl was measured at 30 ° C. using an Ubbelohde type viscosity tube.

<Thickness of polymer film>
The thickness of the polymer film was measured using a micrometer (“Millitron 1245D” manufactured by Fine Wolf Co., Ltd.).

<Thickness spots on polymer film>
The thickness unevenness of the polymer film was measured by randomly extracting 10 points from the film to be measured using a micrometer (“Millitron 1245D” manufactured by Fineryuf Co., Ltd.) and measuring the film thickness. From the maximum value (maximum film thickness), minimum value (minimum film thickness), and average value (average film thickness) of the values of, it was calculated based on the following formula.
Film thickness unevenness (%) = 100 x (maximum film thickness-minimum film thickness) / average film thickness

<Tensile elastic modulus, tensile breaking strength and tensile breaking elongation of polymer film>
A strip-shaped test piece having a flow direction (MD direction) and a width direction (TD direction) of 100 mm × 10 mm, respectively, was cut out from the polymer film to be measured, and a tensile tester (Shimadzu Seisakusho Co., Ltd. “Autograph (registered)” Tensile modulus, tensile strength at break, and elongation at break were measured in each of the MD and TD directions under the conditions of a tensile speed of 50 mm / min and a distance between chucks of 40 mm using the model name AG-5000A). ..

<Coefficient of linear expansion (CTE) of polymer film>
Regarding the flow direction (MD direction) and width direction (TD direction) of the polymer film to be measured, the stretch ratio was measured under the following conditions, and the intervals of 15 ° C. (30 ° C. to 45 ° C., 45 ° C. to 60 ° C.) The expansion / contraction rate / temperature at (...) was measured, this measurement was performed up to 500 ° C., and the average value of all the measured values measured in the MD direction and the TD direction was calculated as the linear expansion coefficient (CTE).
Device name; MAC Science "TMA4000S"
Sample length; 20 mm
Sample width; 2 mm
Temperature rise start temperature; 30 ° C
Temperature rise end temperature; 500 ° C
Heating rate; 5 ° C / min Atmosphere; Argon initial load; 34.5 g / mm2

<Glass transition temperature>
Using a DSC differential thermal analyzer, the glass transition temperature of the polymer film was determined from the presence or absence of heat absorption and heat dissipation due to structural changes in the range from room temperature to 500 ° C. No glass transition temperature was observed in any of the polymer films.

<Evaluation of polymer film: slipperiness>
Two polymer films are overlapped on different surfaces (that is, the outer surface of the film and the inner surface of the film when wound as a film roll are overlapped instead of the same surfaces), and the laminated polymer films are overlapped with the thumb and index finger. The case where the polymer film and the polymer film slipped when sandwiched and lightly rubbed was evaluated as "○" or "good", and the case where the polymer film did not slip was evaluated as "x" or "poor". In some cases, the outer surfaces of the windings or the inner surfaces of the windings do not slip, but this is not an evaluation item.

<Thickness of silane coupling agent layer>
For the thickness (nm) of the silane coupling agent layer (SC layer), a sample obtained by separately applying and drying the silane coupling agent on the washed Si wafer in the same manner as in each Example and Comparative Example was prepared. The thickness of the silane coupling agent layer formed on the Si wafer was measured by an ellipsometry method using a spectroscopic ellipsometer (“FE-5000” manufactured by Photol) under the following conditions.
Reflection angle range; 45 ° to 80 °
Wavelength range; 250 nm to 800 nm
Wavelength resolution; 1.25 nm
Spot diameter; 1 mm
tanΨ; Measurement accuracy ± 0.01
cosΔ; measurement accuracy ± 0.01
Measurement; Method Rotating detector method Deflection angle; 45 °
Incident angle; 70 ° fixed detector; 0 to 360 ° in 11.25 ° increments
Wavelength; 250nm-800nm
The film thickness was calculated by fitting by the nonlinear least squares method. At this time, the model is an Air / thin film / Si model.
n = C3 / λ4 + C2 / λ2 + C1
k = C6 / λ4 + C5 / λ2 + C4
Wavelength-dependent C1 to C6 were obtained by the formula of.

<Peeling strength>
The peel strength (180 degree peel strength) between the inorganic substrate of the laminate and the polymer film was measured under the following conditions according to the 180 degree peel method described in JIS C6471.
Device name: "Autograph (registered trademark) AG-IS" manufactured by Shimadzu Corporation
Measurement temperature: Room temperature Peeling speed: 50 mm / min Atmosphere: Atmosphere Measurement sample width: 10 mm
The measurement was performed immediately after the laminate was prepared and in a nitrogen-substituted inert oven at 450 ° C. for 1 hour, 2 hours and 3 hours, and at 510 ° C. for 1 hour, 2 hours and 3 hours, and 530 ° C. After heat treatment for 1 hour, 2 hours and 3 hours.

<Appearance quality after heat treatment>
Initial and in a nitrogen-substituted inert oven at 450 ° C. for 1 hour, 2 hours and 3 hours heat treatment, 510 ° C. for 1 hour, 2 hours and 3 hours heat treatment, 530 ° C. for 1 hour and 2 hours, After the heat treatment for 3 hours, the appearance quality of the laminate was visually evaluated.

<Manufacturing of polyimide film>
[Manufacturing Example 1]
(Preparation of polyamic acid solution)
After replacing the inside of the reaction vessel equipped with a nitrogen introduction tube, a thermometer, and a stirring rod with nitrogen, 398 parts by mass of 3,3', 4,4'-biphenyltetracarboxylic acid dianhydride (BPDA) and paraphenylenediamine (paraphenylene diamine) ( 147 parts by mass of PDA) is dissolved in 4600 parts by mass of N, N-dimethylacetamide and added, and colloidal silica is dispersed in dimethylacetamide as a lubricant (Nissan Chemical Industry Co., Ltd. "Snowtex (registered trademark)". ) DMAC-ST30 ”) was added so that silica (lubricant) was 0.15% by mass based on the total amount of polymer solids in the polyamic acid solution, and the mixture was stirred at a reaction temperature of 25 ° C. for 24 hours, and Table 1 A brown and viscous polyamic acid solution V1 having the reduced viscosity shown in the above was obtained.

(Preparation of polyimide film)
The polyamic acid solution V1 obtained above is applied to a smooth surface (non-slip material surface) of a long polyester film (“A-4100” manufactured by Toyobo Co., Ltd.) having a width of 1050 mm using a slit die to have a final film thickness (imide). The film was applied so that the film thickness after conversion was 25 μm, dried at 105 ° C. for 20 minutes, and then peeled off from the polyester film to obtain a self-supporting polyamic acid film having a width of 920 mm.
Next, the obtained self-supporting polyamic acid film was gradually heated in a temperature range of 150 ° C. to 420 ° C. by a pin tenter (first stage 180 ° C. × 5 minutes, second stage 270 ° C. × 10 minutes, The third stage was subjected to heat treatment (420 ° C. for 5 minutes) to imidize, and the pin gripping portions at both ends were dropped by slits to obtain a long polyimide film F1 (1000 m roll) having a width of 850 mm. The characteristics of the obtained film F1 are shown in Table 1.

[Manufacturing Example 2]
(Preparation of polyamic acid solution)
After replacing the inside of the reaction vessel equipped with a nitrogen introduction tube, a thermometer and a stirring rod with nitrogen, 223 parts by mass of 5-amino-2- (p-aminophenyl) benzoxazole (DAMBO) and N, N-dimethylacetamide 4416 The colloidal silica dispersion was added as a lubricant together with 217 parts by mass of pyromellitic dianhydride (PMDA), and the silica (lubricant) contained the polymer solid content in the polyamic acid solution. The mixture was added so as to be 0.12% by mass based on the total amount, and the mixture was stirred at a reaction temperature of 25 ° C. for 24 hours to obtain a brown and viscous polyamic acid solution V2 having the reducing viscosity shown in Table 1.

(Preparation of polyimide film)
Instead of the polyamic acid solution V1, the polyamic acid solution V2 obtained above was used, and the temperature was gradually raised in the temperature range of 150 ° C. to 485 ° C. by a pin tenter (first stage 150 ° C. × 5 minutes, 2). A long polyimide film F2 (1000 m roll) having a width of 850 mm was obtained by operating in the same manner as in Production Example 1 except for the steps 220 ° C. × 5 minutes and the third step 485 ° C. × 10 minutes). The characteristics of the obtained film F2 are shown in Table 1.
[Manufacturing Example 3]
(Preparation of polyamic acid solution)
In Production Example 2, the same procedure was carried out except that the colloidal silica dispersion was not added, to obtain a polyamic acid solution V3.

(Preparation of polyimide film)
The polyamic acid solution V3 obtained above was applied to a smooth surface (non-slip material surface) of a long polyester film (“A-4100” manufactured by Toyo Spinning Co., Ltd.) having a width of 1050 mm using a comma coater. The film thickness after imidization) is about 5 μm, then the polyamic acid solution V2 is applied using a slit die so that the final film thickness is 38 μm including V3, and 25 at 105 ° C. After drying for a minute, it was peeled off from the polyester film to obtain a self-supporting polyamic acid film having a width of 920 mm.
Next, the obtained self-supporting polyamic acid film was gradually heated in a temperature range of 180 ° C. to 495 ° C. by a pin tenter (first stage 180 ° C. × 5 minutes, second stage 220 ° C. × 5 minutes, The third stage was subjected to heat treatment (495 ° C. for 10 minutes) to imidize, and the pin gripping portions at both ends were dropped by slits to obtain a long polyimide film F3 (1000 m roll) having a width of 850 mm. The characteristics of the obtained film F3 are shown in Table 1.

<Plasma treatment of film>
The polyimide film was cut to a predetermined size and treated with a single-wafer vacuum plasma apparatus. As the vacuum plasma processing, RIE mode using parallel plate type electrodes and processing by RF plasma are adopted, nitrogen gas is introduced into the vacuum chamber, and high frequency power of 13.54 MHz is introduced, and the processing time is It was set to 3 minutes.

As the base material, an inorganic plate or, in the case of a multilayer thin film, an inorganic substrate on which a thin film was separately formed was used as the base material, and the following thin film was formed.

<Example 1 of forming a metal thin film>
The inorganic substrate was ultrasonically cleaned with ultra-pure and sufficiently dried with dry air through a HEPA filter. Next, the dried inorganic substrate was set in the chamber of the magnetron sputtering apparatus having a gas introduction mechanism and a shutter, and the inorganic substrate was provided with an aluminum mask having a plurality of openings of 50 mm × 80 mm and an interval of 12 mm between the openings. The surface was masked, argon gas was introduced into the chamber so as to be 5 mTorr, and sputtering was performed by applying DC power for 10 seconds using a metal molybdenum target to form a molybdenum thin film on the surface of the inorganic substrate.
The film thickness of the aluminum thin film obtained by sputtering for 600 seconds under the same conditions was measured in advance with a stylus type step meter and found to be 582 nm. Since it is known that the relationship between the sputtering time and the deposition rate is almost linear, the thickness of the molybdenum thin film obtained in 10 seconds by proportional calculation was estimated to be 9.7 nm.

<Formation example 2 of metal thin film>
The inorganic substrate was ultrasonically cleaned with ultra-pure and sufficiently dried with dry air through a HEPA filter. Next, the dried inorganic substrate was set in the chamber of the magnetron sputtering apparatus having a gas introduction mechanism and a shutter, and the inorganic substrate was provided with an aluminum mask having a plurality of openings of 50 mm × 80 mm and an interval of 12 mm between the openings. The surface was masked, argon gas was introduced into the chamber so as to be 5 mTorr, and DC power application sputtering was performed for 30 seconds using a metal tungsten target to form a tungsten thin film on the surface of the inorganic substrate.
Sputtering was performed in advance under the same conditions for 3600 seconds, and the film thickness of the obtained thin film was measured with a stylus-type profilometer and found to be 407 nm. Since it is known that the relationship between the sputtering time and the deposition rate is almost linear, the thickness of the tungsten thin film obtained in 30 seconds by proportional calculation was estimated to be 3.4 nm.

<Formation example 3 of metal thin film>
The inorganic substrate was ultrasonically cleaned with ultra-pure and sufficiently dried with dry air through a HEPA filter. Next, the dried inorganic substrate was set in the chamber of the magnetotron sputtering apparatus having a gas introduction mechanism and a shutter, and the inorganic substrate was provided with an aluminum mask having a plurality of openings of 50 mm × 80 mm and an interval of 12 mm between the openings. The surface is masked, argon gas is introduced into the chamber so as to be 5 mTorr, and a metal molybdenum chip is placed on the metal tungsten target, and DC power application sputtering is performed for 30 seconds on the surface of the inorganic substrate. An alloy thin film of molybdenum and tungsten was formed.
Sputtering was performed in advance under the same conditions for 3600 seconds, and the film thickness of the obtained thin film was measured with a stylus-type profilometer and found to be 523 nm. Since it is known that the relationship between the sputtering time and the deposition rate is almost linear, the thickness of the tungsten thin film obtained in 30 seconds by proportional calculation was estimated to be 4.4 nm. The ratio of the alloy of molybdenum and tungsten determined by fluorescent X-ray was molybdenum: tungsten = 14:86 (elemental ratio).

<Formation example 4 of metal thin film>
The inorganic substrate was ultrasonically cleaned with ultra-pure and sufficiently dried with dry air through a HEPA filter. Next, the dried inorganic substrate was set in the chamber of the magnetron sputtering apparatus having a gas introduction mechanism and a shutter, and the inorganic substrate was provided with an aluminum mask having a plurality of openings of 50 mm × 80 mm and an interval of 12 mm between the openings. The surface was masked, argon gas was introduced into the chamber so as to be 5 mTorr, and DC power application sputtering was performed for 30 seconds using a metal chromium target to form a chromium thin film on the surface of the inorganic substrate.
Sputtering was performed for 600 seconds under the same conditions in advance, and the film thickness of the obtained thin film was measured with a stylus-type profilometer and found to be 730 nm. Since it is known that the relationship between the sputtering time and the deposition rate is almost linear, the thickness of the chromium thin film obtained in 30 seconds by proportional calculation was estimated to be 24 nm.

<Example 5 of forming a metal thin film>
The inorganic substrate was ultrasonically cleaned with ultra-pure and sufficiently dried with dry air through a HEPA filter. Next, the dried inorganic substrate was set in the chamber of the magnetron sputtering apparatus having a gas introduction mechanism and a shutter, and the inorganic substrate was provided with an aluminum mask having a plurality of openings of 50 mm × 80 mm and an interval of 12 mm between the openings. The surface was masked, argon gas was introduced into the chamber so as to be 5 mTorr, and DC power application sputtering was performed for 30 seconds using a metallic nickel-chromium alloy target to form a nickel-chromium alloy thin film on the surface of the inorganic substrate.
The thickness of the obtained nickel-chromium alloy thin film measured by fluorescent X-ray was 160 nm, and the nickel-chromium ratio was nickel: chromium = 60:40 (elemental ratio).

<Example of forming an aluminum oxide film>
The substrate was ultrasonically cleaned with ultra-pure and sufficiently dried with dry air through a HEPA filter. Next, the dried base material was set in the chamber of the magnetron sputtering apparatus having a gas introduction mechanism and a shutter, and the base material was covered with an aluminum mask having a plurality of openings of 50 mm × 80 mm and an interval of 12 mm between the openings. The surface was masked, argon gas was introduced into the chamber so as to be 15 mTorr, and magnetron sputtering was performed for 5 seconds using a metallic aluminum target with an RF power applied at 13.54 MHz to form an aluminum thin film on the surface of the substrate. ..
The film thickness of the aluminum thin film obtained by sputtering for 120 seconds under the same conditions was measured in advance with a stylus type step meter and found to be 405 nm. Since it is known that the relationship between the sputtering time and the deposition rate is almost linear, the thickness of the aluminum thin film obtained in 5 seconds by proportional calculation was estimated to be 16.9 nm.
Next, after forming the aluminum thin film, the inside of the chamber is replaced with oxygen gas, and with oxygen gas flowing so that the inside of the chamber becomes 30 mTorr, reverse sputtering is performed for 10 seconds to oxidize the surface of the aluminum thin film and to oxidize the aluminum oxide film. Was formed.

<Silicon oxide>
A silicon oxide thin film having a thickness of 70 nm was formed by electron beam deposition.

<Silicon nitride>
A silicon nitride thin film having a thickness of 120 nm was formed by a reactive sputtering method.

<Aluminum nitride>
An aluminum nitride thin film having a thickness of 150 nm was formed by a reactive sputtering method.

<Example of forming a composite oxide film of aluminum and silicon>
In the example of forming the composite oxide film of aluminum and silicon, the thin film was formed under the same conditions except that the applied power to the aluminum target was 30 w and the applied power to the silicon dioxide target was 150 w. A thin film of a composite oxide of aluminum and silicon having a ratio of aluminum to silicon of 37:63 (elemental ratio) was obtained.
A thin film deposition experiment for 600 seconds was conducted in advance, and the thickness was measured with a stylus type step meter. Since it was 1134 nm, the deposition film thickness in 10 seconds was estimated to be 18.9 nm.

<Formation of silane coupling agent layer on substrate>
A silane coupling agent layer was formed by the following method using an inorganic substrate or an inorganic substrate after forming a thin film as a base material.

<Application example 1 (spin coating method)>
As a silane coupling agent, 3-aminopropyltrimethoxysilane (“KBM-903” manufactured by Shin-Etsu Chemical Co., Ltd.) was diluted with isopropyl alcohol to 0.5% by mass to prepare a diluted silane coupling agent. The base material was placed on a spin coater manufactured by Japan Create Co., Ltd., 70 ml of isopropyl alcohol was dropped on the center of rotation, the solution was shaken off and dried at 500 rpm, and then about 35 ml of the diluted solution of the silane coupling agent was added to the center of rotation. The mixture was dropped onto the portion and first rotated at 500 rpm for 10 seconds, then the rotation speed was increased to 1500 rpm and rotated for 20 seconds, and the silane coupling agent diluted solution was shaken off. Next, the base material coated with the silane coupling agent was placed on a hot plate heated to 100 ° C. placed in a clean bench so that the silane coupling agent coating surface was facing up, and the substrate was placed with the silane coupling agent coated surface facing up for about 3 minutes. It was heated to obtain a silane coupling agent spin coating coated substrate.
<Coating example 2 (gas phase coating method)>
Using a vacuum chamber having a hot plate, the silane coupling agent was applied to the substrate under the following conditions.
A petri dish was filled with 100 parts by mass of a silane coupling agent (“KBM-903” manufactured by Shin-Etsu Chemical Co., Ltd .: 3-aminopropyltrimethoxysilane) and allowed to stand on a hot plate. At this time, the hot plate temperature is 25 ° C. Next, at a location 300 mm vertically away from the liquid surface of the silane coupling agent, the base material was held horizontally with the thin film surface facing down, the vacuum chamber was closed, and the oxygen concentration was 0.1% by volume or less at atmospheric pressure. Nitrogen gas was introduced until. Next, the introduction of nitrogen gas was stopped, the inside of the chamber was reduced to 3 × 10-4 Pa, the hot plate temperature was raised to 120 ° C., and the temperature was maintained for 10 minutes to expose the silane coupling agent to vapor. After that, the temperature of the hot plate is lowered, and at the same time, clean nitrogen gas is gently introduced into the vacuum chamber to return to atmospheric pressure, the glass plate is taken out, and a silane coupling agent is applied to the hot plate at 100 ° C. in a clean environment. The plate was placed face up and heat-treated for about 3 minutes to obtain a silane coupling agent gas phase coated substrate.

<Example 1>
<Preparation of laminate and evaluation of initial characteristics>
As the inorganic substrate, soda glass having a thickness of 370 mm × 470 mm and a thickness of 1.1 mm was used, a molybdenum thin film was formed according to the above-mentioned formation example, and the thin film layer side was further treated with a silane coupling agent by a spin coating method.
Next, it was temporarily laminated using a laminator (SE650nH manufactured by Climb Products Co., Ltd.) so that the plasma-treated surface of the polyimide film F1 cut into 380 mm × 480 mm and subjected to plasma treatment overlaps the silane coupling agent-treated surface of the inorganic substrate. .. The laminating conditions were an inorganic substrate side temperature of 100 ° C., a roll pressure of 5 kg / cm2 at the time of laminating, and a roll speed of 5 mm / sec. The polyimide film after the temporary lamination was not peeled off by the weight of the film itself, but the adhesiveness was such that it could be easily peeled off when the edge of the film was scratched. Then, the obtained temporary laminated laminated substrate was placed in a clean oven, heated at 200 ° C. for 30 minutes, and then allowed to cool to room temperature to obtain a polymer film laminated substrate. Table 2 shows the characteristics of the obtained laminated substrate. Here, the easily peeled portion is a portion where a composite oxide thin film layer of aluminum and silicon is formed, and the good adhesive portion is a portion where a thin film layer is not formed by masking.

Hereinafter, in the same manner as in Example 1, a laminate was prepared by appropriately changing conditions such as an inorganic substrate, a thin film forming method, a polyimide film, a silane coupling agent coating method, and the presence or absence of plasma treatment of the polyimide film, and the characteristics were evaluated. .. The results are shown in Tables 2, 3 and 4.

In the table, "glass" used was soda glass having a thickness of 370 mm x 470 mm and a thickness of 1.1 mm, and "Si wafer" used a silicon single crystal wafer having a thickness of 8 inches and a thickness of 0.7 mm. The "F3 non-slip surface" is the side of the film F3 using the polyamic acid V3.
Mo: molybdenum thin film, W: tungsten thin film, Mo-W: molybdenum-tungsten alloy thin film, Cr: chromium thin film, Ni-Cr: nickel-chromium alloy thin film, Al2O3: aluminum oxide thin film, AlN: aluminum nitride thin film, Al2O3 −SiOx: Aluminum, silicon composite oxide thin film, SiO2: Silicon oxide thin film, Si3N4 "silicon nitride thin film, Al2O3 / Mo: Aluminum oxide thin film (silane coupling agent side) / molybdenum thin film (inorganic substrate side), and so on. is there.

<Application example 1>
Using the laminate obtained in Example 22, a thin film transistor ray having a bottom gate type structure on a polyimide film was produced on the easily peelable portion by the following steps.
A 100 nm gas barrier film made of SiON was formed on the entire surface of the laminate on the polyimide film side by a reactive sputtering method. Next, an aluminum layer having a thickness of 80 nm was formed by a sputtering method, and a gate wiring and a gate electrode were formed by a photolithography method. Subsequently, an epoxy resin-based gate insulating film (thickness 80 nm) was formed using a slit die coater. Further, a Cr layer of 5 nm and a gold layer of 40 nm were formed by a sputtering method, and a source electrode and a drain electrode were formed by a photolithography method. In addition, an epoxy resin to be an insulating layer and a dam layer is applied using a slit die coater, and a dam layer having a thickness of 250 nm for a semiconductor layer including a source electrode and a drain electrode is formed by ablation with a UV-YAG laser. A circular shape having a diameter of 100 μm was formed, and a via was formed at the same time as a connection point with the upper electrode. Then, polythiophene, which is an organic semiconductor, was applied into the dam by an inkjet printing method, silver paste was embedded in the via portion, and aluminum wiring was further formed as an upper electrode to form a thin film transistor ray having 640 × 480 pixels.
The obtained thin film transistor ray was used as a backplane, and an electrophoresis display medium was superposed on the front plane to form a display element, and the yield and display performance of the transistor were determined by ON / OFF of each pixel. As a result, the thin film transistor rays produced using any of the laminated bodies had good display performance.
After overlaying the front plane on the thin film transistor ray, the polymer film portion is burnt off with a UV-YAG laser along the inside of the outer circumference of the thin film pattern by about 0.5 mm, and a thin razor blade is used from the end of the cut. Peeling was performed so as to scoop up, and a flexible electrophoretic display was obtained. The obtained electrophoretic display showed good display characteristics, and no deterioration in performance was observed even when wound around a round bar having a diameter of 5 mm.

<Application example 2>
After peeling off the flexible electrophoresis display device in Application Example 1, the inorganic substrate was immersed in a 10% aqueous sodium hydroxide solution at room temperature for 20 hours. Then, it was washed with water, further cleaned with a glass cleaning device for a liquid crystal substrate, and after drying, UV ozone cleaning was performed for 3 minutes. After that, the process returned to the step of <Forming a silane coupling agent layer on an inorganic substrate>, and for the subsequent steps, a laminate was obtained by performing the same production method as when the laminate was first produced. The quality of the obtained laminate was good, and it was in a state where it could be sufficiently recycled.

<Application example 3>
The laminate obtained in Example 24 was covered with a stainless steel frame having an opening and fixed to a substrate holder in a sputtering apparatus. The temperature of the laminate was set to 2 ° C. by fixing the substrate holder and the support of the laminate so as to be in close contact with each other and allowing the refrigerant to flow through the substrate holder. First, the surface of the polyimide film of the laminated body was subjected to plasma treatment. The plasma treatment conditions were a frequency of 13.56 MHz, an output of 200 W, and a gas pressure of 1 × 10-3 Torr in argon gas, and the treatment temperature was 2 ° C. and the treatment time was 2 minutes. Then, under the conditions of frequency 13.56 MHz, output 450 W, gas pressure 3 × 10-3 Torr, using a nickel-chromium alloy target, the thickness was increased at a rate of 1 nm / sec by the DC magnetron sputtering method in an argon atmosphere. A nickel-chromium alloy film (underlayer) of 11 nm was formed. Next, the temperature of the laminate was set to 2 ° C., and sputtering was performed. Then, copper was vapor-deposited at a rate of 10 nm / sec to form a copper thin film having a thickness of 0.22 μm. In this way, a laminated board with a base metal thin film forming film was obtained from each laminated body. The thickness of the copper and NiCr layers was confirmed by a fluorescent X-ray method.

Next, the laminated board with the base metal thin film forming film from each film was fixed to the frame made of Cu, and the electrolytic plating solution (copper sulfate 80 g / l, sulfuric acid 210 g / l, HCl, gloss) was used using a copper sulfate plating bath. A thick copper plating layer (thickening layer) having a thickness of 4 μm was formed by immersing in a small amount of the agent) and passing electricity at 1.5 A / dm2. Subsequently, it was heat-treated at 120 ° C. for 10 minutes and dried to form a copper foil layer on the polymer film surface of the laminate.

A photoresist (“FR-200” manufactured by Chypre) was applied to each of the obtained copper foil layers, dried, off-contact exposed with a glass photomask, and further developed with a 1.2 mass% KOH aqueous solution. .. Next, etching was performed with a cupric chloride etching line containing HCl and hydrogen peroxide at a spray pressure of 40 ° C. and 2 kgf / cm2, and a line sequence of line / space = 20 μm / 20 μm was formed as a test pattern. Next, electroless tin plating was applied to a thickness of 0.5 μm, and then annealing treatment was performed at 125 ° C. for 1 hour to obtain a wiring pattern.
The obtained wiring pattern was observed with an optical microscope, and the presence or absence of disconnection / short circuit was checked using a test pattern. As a result, there were no disconnections or short circuits in the wiring pattern, and the pattern shape was also good. Next, the polymer film was peeled off from the glass plate by the same method as in Application Example 1 to obtain a flexible wiring board. The flexibility of the obtained flexible wiring board was good.

<Application example 4>
Using the laminate obtained in Example 18, a tungsten film (thickness 75 nm) was formed on the polyimide film by the vacuum vapor deposition method by the following steps, and further oxidized as an insulating film without touching the atmosphere. A silicon film (thickness: 150 nm) was laminated and formed. Next, a silicon oxide film (thickness 100 nm) to be a base insulating film was formed by a plasma CVD method, and an amorphous silicon film (thickness 54 nm) was laminated and formed without being exposed to the atmosphere.

Next, the hydrogen element of the amorphous silicon film was removed to promote crystallization, and a heat treatment at 500 ° C. was performed for 40 minutes to form a polysilicon film.
A TFT element was manufactured using the portion of the obtained polysilicon film in the easily peelable portion. First, a polysilicon thin film is patterned to form a silicon region having a predetermined shape, and as appropriate, a gate insulating film is formed, a gate electrode is formed, a source region or a drain region is formed by doping the active region, and an interlayer insulating film is formed. , The source electrode and the drain electrode were formed, and the activation treatment was performed to prepare an array of P-channel TFTs using polysilicon.
The polymer film part is burnt off with a UV-YAG laser along the inside of the outer circumference of the TFT array by about 0.5 mm, and peeled off from the end of the cut by using a blade on a thin razor to scoop up the flexible TFT array. Obtained. The peeling was possible with a very small force, and it was possible to peel without damaging the TFT. The obtained flexible TFT array did not show any deterioration in performance even when wound around a 3 mmφ round bar, and maintained good characteristics.

The easily peelable portion of the polymer film laminated substrate of the present invention is to easily peel off the polyimide film on which the electronic device is placed from the inorganic substrate with a very low load after forming the electronic device on the polyimide film. Is possible. Further, since the good adhesive portion stably adheres the film and the inorganic substrate even during various steps of device manufacturing, problems such as peeling during the steps do not occur. Even if the peeled inorganic substrate is recycled, the polyimide film on which the electronic device is mounted can be easily peeled from the inorganic substrate in the same manner as before recycling, which is particularly useful for manufacturing flexible electronic devices. Therefore, it contributes greatly to the industrial world.

1. 1. Flow meter 2. Gas inlet
3. 3. Silane coupling agent tank 4. Hot water tank 5. Heater 6. Processing room 7. Base material
8. exhaust port

Claims (2)

It is a laminate of a heat-resistant polymer film and an inorganic substrate, and the initial peel strength between the heat-resistant polymer film and the inorganic substrate and the peel strength when cooled to room temperature after heat treatment at 450 ° C in a nitrogen environment are as follows. meet the relationship,
0.05 ≤ F0 ≤ 3.00
dFt = (Ft-F0) / t
-0.15 ≤ dFt ≤ +0.15
0.02 ≤ Ft
Here, the F0 [N / cm]: initial peel strength t [hr]: integer Ft ranging heat treatment time of 1 to 3 nitrogen environment under 450 ℃ [N / cm]: in peel strength after the heat treatment time t Yes,
The initial peel strength between the heat-resistant polymer film and the inorganic substrate and the peel strength when cooled to room temperature after heat treatment at 510 ° C. in a nitrogen environment satisfy the following relational expressions.
0.05 ≤ F0 ≤ 3.00
dFs = (Fs --F0 ) / s
--0.15 ≤ dFs ≤ +0.15
0.02 ≤ Fs
In addition, here
F0 [N / cm]: Initial peel strength
s [hr]: Heat treatment time at 510 ° C. in a nitrogen environment An integer in the range 1-3
Fs [N / cm]: Peeling strength after s time of heat treatment.
A silane coupling agent layer is provided between the heat-resistant polymer film and the inorganic substrate.
A laminate that satisfies any of the following (1) to (4).
(1) A thin film layer of at least one metal selected from molybdenum and tungsten is provided between the silane coupling agent layer and the inorganic substrate.
(2) An aluminum oxide layer is provided between the silane coupling agent layer and the inorganic substrate.
(3) A composite oxide layer of aluminum and silicon is provided between the silane coupling agent layer and the inorganic substrate.
(4) Between the silane coupling agent layer and the inorganic substrate, at least on the side in contact with the silane coupling agent layer is selected from aluminum oxide, aluminum nitride, silicon oxide, silicon nitride, and a composite oxide of aluminum and silicon. It has a thin film layer containing one or more materials and a thin film layer containing at least one or more materials selected from at least molybdenum, tungsten, chrome, and nickel-chromium alloys on the side in contact with the inorganic substrate. The laminate according to claim 1, characterized in that it is used for forming an electronic device.

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