JP2018126922A - Laminate - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a polyimide laminated substrate in which device destruction is hard to occur in peeling a polyimide film, to which device formation is performed, from an inorganic substrate.SOLUTION: By using a polyimide film laminated substrate that is stable even after performing heating treatment at temperature exceeding 510°C, and can be peeled by low and constant force, device destruction in peeling is suppressed, and productivity is improved. Silane coupling agent treatment is performed to an inorganic substrate in which one type or more metal thin film selected from molybdenum, tungsten, chromium, and nickel-chromium alloy is formed at least on a part of a one side of the inorganic substrate, and more preferably a thin film made of complex oxide of aluminum and silicon is continuously or discontinuously formed on the thin film, and furthermore, a polyimide film layer is laminated on a silane coupling agent layer to form a laminate. An obtained laminate maintains the state of small peel strength even if heating treatment is performed at 450°C to 510°C for a long time.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a laminate of an inorganic substrate used as a temporary support substrate at the time of electronic device formation and a heat-resistant polymer film that can constitute a part of the electronic device, particularly when exposed to a high temperature at the time of device formation. The present invention also relates to a laminate that can peel a heat-resistant polymer film layer from an inorganic substrate without stress.

  In recent years, for the purpose of reducing the weight, size and thickness of functional elements such as semiconductor elements, MEMS elements, and display elements, and increasing flexibility, technological developments for forming these elements on polymer films have been actively conducted. That is, as a material for the base material of electronic parts such as information communication equipment (broadcast equipment, mobile radio, portable communication equipment, etc.), radar, high-speed information processing equipment, etc., conventionally, it has heat resistance and information communication equipment signals. Ceramics that can cope with higher frequency bands (up to the GHz band) have been used, but since ceramics are not flexible and difficult to reduce in thickness, there is a drawback that applicable fields are limited. A polymer film is used as a substrate.

  When functional elements such as semiconductor elements, MEMS elements, and display elements are formed on the surface of a polymer film, it is ideal to process them using a so-called roll-to-roll process that uses the flexibility of polymer films. It is said that. However, in the industry such as the semiconductor industry, the MEMS industry, and the display industry, a process technology for a rigid flat substrate such as a wafer base or a glass substrate base has been constructed so far. Therefore, in order to form a functional element on a polymer film using existing infrastructure, the polymer film is bonded to a rigid support made of an inorganic material 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 thereon and then peeled off from the support.

  By the way, in a process of forming a desired functional element on a laminate in which a polymer film and an inorganic support are bonded together, the laminate is often exposed to high temperatures. For example, in the formation of functional elements such as polysilicon and 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. Further, in order to heat and dehydrogenate amorphous silicon to form a low temperature polysilicon, a temperature of about 450 ° C. to 600 ° C. Heating may be required. Therefore, although heat resistance is calculated | required for the polymer film which comprises a laminated body, the polymer film which can be practically used in this high temperature range is limited as a real problem. In addition, it is generally considered to use a pressure-sensitive adhesive or an adhesive for laminating the polymer film to the support, but the bonding surface of the polymer film and the support at that time (that is, an adhesive for laminating or the like) The adhesive also requires heat resistance. However, since a normal bonding adhesive or pressure-sensitive adhesive does not have sufficient heat resistance, bonding with an adhesive or pressure-sensitive adhesive cannot be applied when the functional element formation temperature is high.

  Since there is no heat-resistant adhesive means for attaching a polymer film to an inorganic substrate, in such applications, a polymer solution or a polymer precursor solution is applied onto an inorganic substrate and dried and cured on a support to form a film. Techniques used for such applications are known. Further, in order to facilitate peeling, a technique for forming a plurality of layers and using a part as a sacrificial layer, or a technique for functionally separating an adhesive / peeling function and a film physical property has been proposed (patent) Literatures 1-3).

  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 often breaks when peeled from the support. In particular, it is extremely difficult to peel a large-area film from a support, and it is not possible to obtain a yield that is about industrially valid. In view of such circumstances, as a laminate of a polymer film and a support for forming a functional element, a polyimide film that has excellent heat resistance and is strong and can be thinned from an inorganic substance via a silane coupling agent. A laminated body formed by bonding to a support (inorganic layer) is proposed (Patent Documents 4 to 5).

JP 2016-120629 A JP 2016-120630 A Japanese Patent No. 4834758 JP 2010-283262 A JP 2011-11455 A

  Based on the technical background as described above, the process of creating an electronic device on a polymer film is preferably performed at a higher processing temperature in order to obtain a high-quality crystalline thin film. In view of the nature, conditions have been set in the balance of conflicting elements that the heating temperature should be minimized. However, since it is possible to use a heat-resistant polymer film having good physical properties instead of a process using a precursor solution, a demand for further increasing the processing temperature has been revealed from the electronic device fabrication technology side. Yes. That is, there is an increasing demand for a heat treatment temperature that has been limited to 400 ° C. to less than 450 ° C. up to 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 are more affected by the high temperature exposure on the adhesive interface between the polymer film and the inorganic substrate than the thermal degradation problem of the polymer film, and the peel strength. It was expected that trouble would occur that the polymer film peeled off during the process.
However, in reality, the fact that the adhesive strength between the polymer film and the inorganic substrate increases conversely and the problem that peeling becomes difficult is recognized.
The phenomenon that the peel strength increases is the fact that many heat-resistant polymers are condensation-type polymers, and the decomposition reaction and the recombination reaction are balanced even in the temperature range around 500 ° C. where ordinary polymers are almost decomposed. On the other hand, since high temperature induces very high chemical activity, it can be interpreted that some chemical bond is generated between the surface of the inorganic substrate and the activated heat-resistant polymer.

  As a result of intensive studies to solve the above-mentioned problems, the inventors of the present invention have kept the peel strength change width accompanying heat treatment at a high temperature within a predetermined range, and at the same time, without causing a peeling accident during the processing process. It has been found 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] Laminated body of heat-resistant polymer film and inorganic substrate, initial peel strength between heat-resistant polymer film and inorganic substrate, and peel strength when cooled to room temperature after 450 ° C heat treatment 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 Ft [N / cm]: peel strength after heat treatment t time [1 to 3] 2] A laminate of a heat-resistant polymer film and an inorganic substrate, which has an initial peel strength between the heat-resistant polymer film and the inorganic substrate, and a 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 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 time [ 3] The laminate according to [1] or [2], wherein a silane coupling agent layer is provided between the heat-resistant polymer film and the inorganic substrate.
[4] Any one of [1] to [3], wherein a thin film layer of at least one metal selected from molybdenum, tungsten, and chromium is provided between the silane coupling agent layer and the inorganic substrate. The laminated body as described in.
[5] The laminate according to any one of [1] to [4], wherein an aluminum oxide layer is provided between the silane coupling agent layer and the inorganic substrate.
[6] The laminate according to any one of [1] to [4], wherein a silicon compound layer is provided between the silane coupling agent layer and the inorganic substrate.
[7] The laminate according to any one of [1] to [4], wherein a composite oxide layer of aluminum and silicon is provided between the silane coupling agent layer and the inorganic substrate.
[8] Between the silane coupling agent layer and the inorganic substrate, at least 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 is characterized by having a thin film layer containing one or more materials and a thin film layer containing at least one material selected from molybdenum, tungsten, chromium and nickel-chromium alloy on the side in contact with the inorganic substrate [1] To [3].
[9] Between the silane coupling agent layer and the inorganic substrate, at least the 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], comprising a metal thin film containing one kind selected from chromium and a nickel-chromium alloy.
[10] The laminate according to any one of [1] to [9], wherein the laminate is used as a temporary support substrate for forming an electronic device.

Furthermore, 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 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 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 at 510 ° C. in nitrogen environment Integer Fu [N / cm]: Peel strength after heat treatment u time

The effect of the present invention is that, firstly, the change in peel strength during high-temperature treatment is guided to a pattern that satisfies the specific mathematical formula described in the claims, thereby preventing a peel accident even during the processing process and simultaneously forming a device. Later, it was realized that the device can be easily peeled off from the inorganic substrate together with the polymer film.
The specific means for deriving such a change pattern of the peel strength will be described in detail. Basically, by inserting a specific thin film layer between the polymer film and the inorganic substrate, the peel strength can be increased. Realize the change pattern. The thin film layer preferably includes a silane coupling agent layer, and preferably includes at least one inorganic layer, and more preferably includes 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 is applicable not only to liquids but also to plastic deformation layers existing on solid surfaces at the molecular level), and promotes stable initial adhesion.
On the other hand, the chemical affinity for a silane coupling agent layer that has undergone a condensation reaction or a polymer film layer in a stationary state without physical change is low in a wide temperature range, and is high even when high-temperature heat treatment is applied. Does not significantly affect the peel strength between the molecular film layer and the inorganic substrate layer.

  In the present invention, in particular, between the silane coupling agent layer and the inorganic substrate, at least 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. An oxide having a structure including a thin film layer including one or more materials and a thin film layer including at least one material selected from molybdenum, tungsten, chromium, and a nickel-chromium alloy on a side in contact with the inorganic substrate. In addition, 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 alloy used in the present invention has a stable passive state formed on the surface. Forms a stable weak adhesion state with the thin film layer and has low reactivity, so the weak adhesion state does not change even when exposed to high temperatures for a long time, and as a result, stable peeling performance can be maintained. .

  As a result, in the region that enters the peel strength change pattern during the high temperature treatment of the present invention that is realized, it occurs when gas is generated from the polymer film during high temperature heat treatment as well as prevention of peeling accidents during the process. It balances the necessary minimum adhesiveness that can suppress uki (or bubbles and blisters) and good peeling performance that allows the device boarder to peel without applying stress to the device portion.

Furthermore, 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 cutting the polymer film. A functional element part formed on the polymer film of the easy-peeling part by making a cut along the periphery of the easy-peeling part and making a good adhesive part that is an area that cannot be easily separated. Can be peeled off from the inorganic substrate integrally with the polymer film.
If the polymer film laminated substrate of the present invention is used, 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 with electromagnetic induction elements, printed coils, printed antennas, biosensors, composite devices such as electronic devices, electromechanical devices, active elements, passive elements formed on polymer films Can be realized.

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

<Inorganic substrate>
In the present invention, an inorganic substrate is used as a support for the polymer film. In addition, when a flexible electronic device is manufactured by forming an electronic device on a polymer film, the inorganic substrate is used for temporarily supporting the polymer film material.
The inorganic substrate may be any plate-like material that can be used as a substrate made of an inorganic substance, for example, a glass plate, a ceramic plate, a semiconductor wafer, a material mainly made of metal, etc., and these glass plates, ceramic plates, Examples of semiconductor wafers and metal composites include those obtained by laminating them, those in which they are dispersed, and those containing these fibers.

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

  The semiconductor wafer is not particularly limited, but silicon wafer, germanium, silicon-germanium, gallium-arsenic, aluminum-gallium-indium, nitrogen-phosphorus-arsenic-antimony, SiC, InP (indium phosphorus), InGaAs, GaInNAs, Examples of the wafer include LT, LN, ZnO (zinc oxide), CdTe (cadmium tellurium), and ZnSe (zinc selenide). 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 invar alloy, and super invar alloy. In addition, a multilayer metal plate formed by adding other metal layers and ceramic layers to these metals is also included. In this case, if the overall linear expansion coefficient (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 strong properties such as adhesion to the polymer film, no diffusion, and good chemical resistance and heat resistance. Although it is not a thing, Cr, Ni, TiN, Mo containing Cu etc. are mentioned as a suitable example.

The planar portion of the inorganic substrate is desirably 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 is preferably 10 mm or less, more preferably 3 mm or less, and even more preferably 1.3 mm or less from the viewpoint of handleability. 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 a large area from the viewpoint of production efficiency and cost of the polymer film laminated substrate and the flexible electronic device. Specifically, it is preferably 1000 cm 2 or more, more preferably 1500 cm 2 or more, and further preferably 2000 cm 2 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 complexity, the polymer is simply used. The melting point and 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 observing the thermal deformation behavior when heated at the corresponding temperature.

Examples of the polymer film in the present invention include aromatic polyimides such as polyimide, polyamideimide, polyetherimide, and fluorinated polyimide, and polyimide resins such as alicyclic polyimide, polyethylene, polypropylene, polyethylene terephthalate, polybutylene terephthalate, and polyethylene-2. Copolyesters such as wholly aromatic polyesters and semi-aromatic polyesters such as 1,6-naphthalate, copolymerized (meth) acrylates represented by polymethyl methacrylate, polycarbonate, polyamide, polysulfone, polyethersulfone, polyetherketone, acetic acid Cellulose, cellulose nitrate, aromatic polyamide, polyvinyl chloride, polyphenol, polyarylate, polyphenylene sulfide, polyphenyleneoxy It can be exemplified by films of polystyrene.
However, since it is a major premise that the present invention is used in a process involving heat treatment at 450 ° C. or higher, there are only a limited number of examples of the polymer films exemplified. 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 amide aromatic film, an aromatic amide imide film, and an aromatic benzoxazole. A film, an aromatic benzothiazole film, and an aromatic benzimidazole film.

  Details of the polyimide resin film will be described below. In general, a polyimide resin film is obtained by applying a polyamic acid (polyimide precursor) solution obtained by reacting diamines and tetracarboxylic acids in a solvent to a support for preparing a polyimide film, followed by drying to obtain a green film (hereinafter, referred to as a polyimide film). It is also referred to as “polyamic acid film”), and it is obtained by subjecting the green film to high-temperature heat treatment on a support for preparing a polyimide film or in a state peeled from the support to cause a dehydration ring-closing reaction.

  There is no restriction | limiting in particular as diamine which comprises a polyamic acid, The aromatic diamine, aliphatic diamine, alicyclic diamine etc. which are normally used for a polyimide synthesis | combination 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 a high elastic modulus, a low heat shrinkage, and a low linear expansion coefficient as well as a high heat resistance. Diamines may be used alone or in combination of two or more.

  The aromatic diamine having a benzoxazole structure is not particularly limited. 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-aminobenzoxazolo) -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'] Examples thereof include bisoxazole and 2,6- (3,3′-diaminodiphenyl) benzo [1,2-d: 4,5-d ′] bisoxazole.

Examples of the aromatic diamine other than the aromatic diamine having the benzoxazole structure described above include 2,2′-dimethyl-4,4′-diaminobiphenyl, 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 Sulfide, bis [4- (3-aminophenoxy) phenyl] sulfone, 2,2-bis [4- (3-aminophenoxy) phenyl] propyl Pan, 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'-diaminodiphenyl sulfoxide, 3,3'-diaminodiphenyl sulfone, 3,4'-diaminodiphenyl sulfone, 4,4'-diaminodiphenyl sulfone, 3 , 3'-diaminobenzophenone, 3,4'-diaminobenzo Zofenon, 4,4'-diamino benzophenone, 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-dimethyl Phenyl] 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-a Nophenoxy) phenyl] propane, 1,3-bis [4- (3-aminophenoxy) phenyl] propane, 3,4'-diaminodiphenyl sulfide, 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-methylphenyl) Xyl) -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′-dibi Phenoxybenzophenone, 4,4'-diamino-5,5'-dibiphenoxybenzophenone, 3,4'-diamino-4,5'-dibiphenoxybenzophenone 3,3′-diamino-4-biphenoxybenzophenone, 4,4′-diamino-5-biphenoxybenzophenone, 3,4′-diamino-4-biphenoxybenzophenone, 3,4′-diamino-5′-bi Phenoxybenzophenone,
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) Benzoyl) 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] benzonitrile, and a part or all of the hydrogen atoms on the aromatic ring of the aromatic diamine are halogen atoms An alkyl group having 1 to 3 carbon atoms or an alkoxyl group, a cyano group, an alkyl group or an alkoxyl group in which some or all of the hydrogen atoms are substituted with halogen atoms, or a halogenated alkyl group having 1 to 3 carbon atoms or an alkoxyl group And aromatic diamines substituted with

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, 4,4′-methylenebis (2,6-dimethylcyclohexylamine), and the like.
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, and still more preferably 5% by mass or less of the total diamines. It is. In other words, the aromatic diamine is preferably 80% by mass or more of the total diamines, more preferably 90% by mass or more, and still more preferably 95% by mass or more.

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

Examples of the alicyclic tetracarboxylic acids include alicyclic tetracarboxylic acids such as cyclobutanetetracarboxylic acid, 1,2,4,5-cyclohexanetetracarboxylic acid, and 3,3 ′, 4,4′-bicyclohexyltetracarboxylic acid. Carboxylic acids and their acid anhydrides are mentioned. Among these, dianhydrides having two anhydride structures (for example, cyclobutanetetracarboxylic dianhydride, 1,2,4,5-cyclohexanetetracarboxylic dianhydride, 3,3 ′, 4,4 '-Bicyclohexyltetracarboxylic dianhydride and the like) are preferred. In addition, alicyclic tetracarboxylic acids may be used independently and may use 2 or more types together.
In the case where importance is attached to transparency, the alicyclic tetracarboxylic acids are, for example, preferably 80% by mass or more of all tetracarboxylic acids, more preferably 90% by mass or more, and further preferably 95% by mass or more.

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 acid anhydrides thereof. Examples of such aromatic tetracarboxylic acids include pyromellitic dianhydride, 3,3 ′, 4,4′-biphenyltetracarboxylic dianhydride, 4,4′-oxydiphthalic dianhydride, 3 , 3 ′, 4,4′-benzophenone tetracarboxylic dianhydride, 3,3 ′, 4,4′-diphenylsulfone tetracarboxylic dianhydride, 2,2-bis [4- (3,4-di Carboxyphenoxy) phenyl] propanoic anhydride and the like.
In the case of placing importance on heat resistance, the aromatic tetracarboxylic acids are, for example, preferably 80% by mass or more, more preferably 90% by mass or more, and still more preferably 95% by mass or more of all tetracarboxylic acids.

For example, spin coating, doctor blade, applicator, comma coater, screen printing method, slit coating, reverse coating, dip coating, curtain coating can be applied to the silane coupling agent layer. Conventionally known solution application means such as slit die coating can be appropriately used.
For example, after applying a polyamic acid (polyimide precursor) solution obtained by reacting diamines and tetracarboxylic acids in a solvent in a solvent to a predetermined thickness on an inorganic substrate and drying, It can be obtained by a thermal imidation method in which a dehydration ring-closing reaction is performed by heat treatment at high temperature or a chemical imidation 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 is preferably 250 μm or less, more preferably 150 μm or less, and still more preferably 90 μm or less for use as a flexible electronic device.

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

  The thermal shrinkage rate between 30 ° C. and 500 ° C. of the polymer film of the present invention 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 strength at break of the polymer film in the present invention is preferably 60 MPa or more, more preferably 120 MP or more, and further preferably 240 MPa or more. The upper limit of the tensile strength at break 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. When the thickness unevenness exceeds 20%, it tends to be difficult to apply to narrow portions. In addition, the thickness unevenness of a film can be calculated | required based on the following formula, for example, extracting about 10 points | pieces positions from a film to be measured at random with a contact-type film thickness meter, measuring film thickness.
Film thickness spots (%)
= 100 × (maximum film thickness−minimum film thickness) ÷ average film thickness

  The polymer film according to 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 production, and a roll wound around a winding core. More preferably in the form of a polymer film.

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

<Surface activation treatment of polymer film>
The polymer film used in the present invention is preferably subjected to a surface activation treatment. By subjecting the polymer film to surface activation treatment, the surface of the polymer film is modified to a state in which a functional group exists (so-called activated state), and adhesion 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 intro treatment. it can. Examples of the wet surface treatment include a treatment in which the polymer film surface is brought into contact with an acid or alkali 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 generates more active functional groups. The generated functional group is bonded to the silane coupling agent layer by hydrogen bonding or chemical reaction, and the polymer film layer and the silane coupling agent layer can be firmly bonded.

In the present invention, the silane coupling agent means a compound that is physically or chemically interposed between the inorganic substrate and the polymer film layer and has an action of increasing 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. Preferable specific examples of the silane coupling agent include 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-glycidoxypropyltriethoxysilane, vinyltrichlorosilane, Vinyltrimethoxysilane, vinyltriethoxysila 2- (3,4-epoxycyclohexyl) ethyltrimethoxysilane, 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropylmethyldiethoxysilane, 3-glycidoxypropyltriethoxysilane, p-styryl Trimethoxysilane, 3-methacryloxypropylmethyldimethoxysilane, 3-methacryloxypropyltrimethoxysilane, 3-methacryloxypropylmethyldiethoxysilane, 3-methacryloxypropyltriethoxysilane, 3-acryloxypropyltrimethoxysilane, N-phenyl-3-aminopropyltrimethoxysilane, N- (vinylbenzyl) -2-aminoethyl-3-aminopropyltrimethoxysilane hydrochloride, 3-ureidopropyltriethoxysilane, 3-chloropropyl Limethoxysilane, 3-mercaptopropylmethyldimethoxysilane, 3-mercaptopropyltrimethoxysilane, bis (triethoxysilylpropyl) tetrasulfide, 3-isocyanatopropyltriethoxysilane, tris- (3-trimethoxysilylpropyl) isocyanurate Chloromethylphenethyltrimethoxysilane, chloromethyltrimethoxysilane, aminophenyltrimethoxysilane, aminophenethyltrimethoxysilane, aminophenylaminomethylphenethyltrimethoxysilane, and the like.

  As the silane coupling agent that can be used in the present invention, in addition to the above, n-propyltrimethoxysilane, butyltrichlorosilane, 2-cyanoethyltriethoxysilane, cyclohexyltrichlorosilane, decyltrichlorosilane, diacetoxydimethylsilane, Diethoxydimethylsilane, dimethoxydimethylsilane, dimethoxydiphenylsilane, dimethoxymethylphenylsilane, dodecyltrichlorosilane, dodecyltrimethoxysilane, ethyltrichlorosilane, hexyltrimethoxysilane, octadecyltriethoxysilane, octadecyltrimethoxysilane, n-octyltri Chlorosilane, n-octyltriethoxysilane, n-octyltrimethoxysilane, triethoxyethylsilane, triethoxymethylsila , Trimethoxymethylsilane, trimethoxyphenylsilane, pentyltriethoxysilane, pentyltrichlorosilane, triacetoxymethylsilane, trichlorohexylsilane, trichloromethylsilane, trichlorooctadecylsilane, trichloropropylsilane, trichlorotetradecylsilane, trimethoxypropylsilane , Allyltrichlorosilane, allyltriethoxysilane, allyltrimethoxysilane, diethoxymethylvinylsilane, dimethoxymethylvinylsilane, trichlorovinylsilane, triethoxyvinylsilane, vinyltris (2-methoxyethoxy) silane, trichloro-2-cyanoethylsilane, diethoxy (3 -Glycidyloxypropyl) methylsilane, 3-glycidyloxypropyl (dimethoxy) Methylsilane, it can also be used, such as 3-glycidyloxypropyltrimethoxysilane.

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-glycidoxypropyltriethoxysilane, aminophenyltrimethoxy Silane, amino phenethyltrimethoxysilane, such as aminophenyl aminomethyl phenethyltrimethoxysilane the like. In the case where particularly high heat resistance is required in the process, it is desirable to use an aromatic group between Si and an amino 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, methyl 3-mercaptopropionate, 3-mercapto 2-butanol, butyl 3-mercaptopropionate, 3- (dimethoxymethylsilyl) -1-propanethiol, 4- (6-mercaptohexaloyl) benzyl alcohol, 11-amino-1-undecenethiol, 11-mercapto Undecylphosphonic acid, 11-mercaptoundecyltrifluoroacetic acid, 2,2 '-(ethylenedioxy) diethanethiol, 11-mercaptoundecyltri (ethylene glycol), (1-mercaptoundec-11-yl) Tetra (ethylene glycol), 1- ( Methylcarboxy) undec-11-yl) hexa (ethylene glycol), hydroxyundecyl disulfide, carboxyundecyl disulfide, hydroxyhexadodecyl disulfide, carboxyhexadecyl disulfide, tetrakis (2-ethylhexyloxy) titanium, titanium dioctyloxybis ( Octylene glycolate), zirconium tributoxy monoacetylacetonate, zirconium monobutoxyacetylacetonate bis (ethyl acetoacetate), zirconium tributoxy monostearate, acetoalkoxyaluminum diisopropylate, 3-glycidyloxypropyltrimethoxysilane, 2,3-butanedithiol, 1-butanethiol, 2-butanethiol, cyclohexanethiol, Clopentanethiol, 1-decanethiol, 1-dodecanethiol, 2-mercaptopropionic acid-2-ethylhexyl, ethyl 3-mercaptopropionate, 1-heptanethiol, 1-hexadecanethiol, hexylmercaptan, isoamyl mercaptan, isobutyl mercaptan, 3-mercaptopropionic acid, 3-mercaptopropionic acid-3-methoxybutyl, 2-methyl-1-butanethiol, 1-octadecanethiol, 1-octanethiol, 1-pentadecanethiol, 1-pentanethiol, 1-propanethiol 1-tetradecanthiol, 1-undecanthiol, 1- (12-mercaptododecyl) imidazole, 1- (11-mercaptoundecyl) imidazole, 1- (10-mercaptodecyl) Midazole, 1- (16-mercaptohexadecyl) imidazole, 1- (17-mercaptoheptadecyl) imidazole, 1- (15-mercapto) dodecanoic acid, 1- (11-mercapto) undecanoic acid, 1- (10-mercapto ) Decanoic acid can also be used.

<Method for forming 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 the surface of either 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 solution obtained by diluting the silane coupling agent with a solvent such as alcohol is used, and a spin coating method, a curtain coating method, a dip coating method, a slit die coating method, a gravure coating method, a bar coating method, 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 to dry quickly after the application, and to perform a heat treatment 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 coated surface are bonded by a chemical reaction.

Further, the silane coupling agent layer can be formed by a vapor deposition method. Specifically, the substrate is formed by exposing the substrate to vapor of the silane coupling agent, that is, a substantially gaseous silane coupling agent. The vapor of the silane coupling agent can be obtained by heating the silane coupling agent in a liquid state to a temperature from 40 ° C. to about the boiling point of the silane coupling agent. Although the boiling point of a silane coupling agent changes with chemical structures, it is the range of about 100-250 degreeC in general. 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 under pressure, normal pressure, or reduced pressure, but is preferably under normal pressure or reduced pressure when promoting vaporization of the silane coupling agent. Since many silane coupling agents are flammable liquids, it is preferable to perform the vaporizing operation in an airtight 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 within 20 hours, more preferably within 60 minutes, further preferably within 15 minutes, and most preferably within 1 minute.
The temperature of the substrate during the exposure of the substrate to the silane coupling agent is controlled to an appropriate temperature between −50 ° C. and 200 ° C. depending on the type of silane coupling agent and the thickness of the desired silane coupling agent layer. It is preferable to do.
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 this heating, the hydroxyl group on the substrate surface reacts with the alkoxy group or 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 be deteriorated. If the heating time after exposure is too short, the treatment effect cannot be obtained. In addition, when the substrate temperature during the exposure to the silane coupling agent is already 80 ° C. or higher, the heating after the exposure can be omitted.
In the present invention, it is preferable to expose the surface of the substrate on which the silane coupling agent layer is to be formed to face downward by using a vapor deposition method while exposing the silane coupling agent vapor. In the method of applying the silane coupling agent solution, since the coating surface of the base material inevitably faces upwards before and after coating, it is impossible to deny the possibility that suspended foreign matters in the work environment will deposit on the surface of the base material. . However, the vapor deposition method can hold the surface of the base material on which the silane coupling agent layer is to be formed facing downward, so that foreign substances in the environment can be found on the surface of the base material (or thin film surface) or the surface of the silane coupling agent layer. The possibility of adhesion is reduced.
In addition, it is preferable to clean the base-material surface before a silane coupling agent process by means, such as short wavelength UV / ozone irradiation, or a liquid cleaning agent.

  The film thickness of the silane coupling agent layer is extremely thin compared to the substrate, polymer film, etc., and is negligible from the mechanical design point of view. 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 in practical use, more preferably 50 nm or less, and further preferably 10 nm or less. However, when the calculation is in the region of 5 nm or less, the silane coupling agent layer may exist in a cluster form, not as a uniform coating film. In addition, the film thickness of a silane coupling agent layer can be calculated | required from the ellipsometry method or calculating from the density | concentration and application amount of the silane coupling agent solution at the time of application | coating.

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

In the present invention, a thin film of at least one metal selected from molybdenum and tungsten is used as a single metal thin film. In the present invention, when each single metal thin film is used, it is preferable to use a metal thin film having a purity of at least 85% or more, preferably a purity of 92% or more, and more preferably a purity of 98% or more. As an exception, an alloy made 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 (element 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 vapor 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, after the metal thin film is formed, the surface non-conductive layer can be strengthened by oxygen plasma treatment, anodizing treatment, atmospheric pressure plasma treatment or the like.

  As another preferred embodiment of the present invention, a form in which an aluminum oxide thin film layer is inserted between the silane coupling agent layer and the inorganic substrate can be exemplified. Such an aluminum oxide thin film layer is preferably formed continuously or discontinuously 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 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 mode in which an aluminum nitride thin film layer is inserted between the silane coupling agent layer and the inorganic substrate can be exemplified. The aluminum nitride thin film layer is preferably formed continuously or discontinuously on at least a part of one surface of the inorganic plate. In the present invention, it is preferable to use aluminum nitride having a purity of 85% or more, preferably 92% or more, and more preferably 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.

  Another preferred embodiment of the present invention is a mode in which a silicon compound thin film is inserted between the silane coupling agent layer and the inorganic substrate. The silicon compound thin film layer is preferably formed continuously or discontinuously 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 using a CVD method, a reactive sputtering method, or the like. For 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 mode in which a thin film of aluminum and silicon composite oxide is inserted between the silane coupling agent layer and the inorganic substrate can be exemplified. Such a thin film layer of a composite oxide of aluminum and silicon (silicon) is preferably formed continuously or discontinuously on a part of at least one surface of the inorganic plate. A preferable ratio of aluminum to silicon in the thin film of the present invention is aluminum / silicon = 90/10 to 30/70 (element ratio), and preferably 90/10 to 50/50. If the silicon ratio increases beyond this range, the interaction with the silane coupling agent becomes too strong, and peeling may be hindered. 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 vapor 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, after forming a metal aluminum or metal silicon thin film, a method of oxidizing aluminum by oxygen plasma treatment, anodizing treatment, atmospheric pressure plasma treatment, etc., a method of depositing a composite oxide thin film using reactive sputtering, and reactivity Examples include a method using an ion cluster method. Further, reactive sputtering of metal aluminum and vapor deposition or sputtering of silicon oxide can be used in combination.

In the present invention, as the thin film layer inserted between the silane coupling agent layer and the inorganic substrate, each of the thin film layers exemplified above can be inserted singly or in a plurality. 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, and then an aluminum oxide thin film layer, an aluminum nitride thin film layer, and a silicon compound thin film. It is preferable to insert a multilayer thin film layer in which at least one thin film layer selected from a layer and a composite oxide thin film layer of aluminum and silicon is formed. 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,
It is. Here, the oxide layer is one or more thin film layers selected from an aluminum oxide thin film layer, a silicon oxide thin film layer, and a composite oxide thin film layer of aluminum and silicon, and the nitride layer is an aluminum nitride thin film layer. 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, or a nickel-chromium alloy, or an alloy thin film layer thereof. When using a nickel-chromium alloy, a preferable alloy composition is nickel / chromium = 75/25 to 10/90 (element ratio).

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

  The pressure heat treatment may be performed while heating a press, a laminate, a roll laminate, or the like, for example, in an atmospheric pressure atmosphere or in a vacuum. A method of heating under pressure in a flexible bag can also be applied. From the viewpoint of improving productivity and reducing the processing cost brought about by high productivity, press or roll lamination in an air atmosphere is preferable, and a method using rolls (roll lamination 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. If the pressure is too low, a non-adhering part may be produced, and adhesion may be insufficient. 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. If the temperature is too low, the adhesion tends to be weak.
The pressure heat treatment can be performed in an atmospheric pressure atmosphere as described above. However, in order to obtain a stable peel strength on the entire surface, it is preferably performed under vacuum. At this time, the degree of vacuum by a normal oil rotary pump is sufficient, and about 10 Torr or less is sufficient.
As an apparatus that can be used for pressure heat treatment, for example, “11FD” manufactured by Imoto Seisakusho can be used to perform pressing in a vacuum, and a roll-type film laminator in vacuum or a vacuum is used. For example, “MVLP” manufactured by Meiki Seisakusho Co., Ltd. can be used to perform vacuum laminating such as a film laminator that applies pressure to the entire glass surface at once with a thin rubber film.

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

As described above, the following laminate (1) or (2) in the present invention can be obtained.
(1)
A laminate of a heat resistant polymer film and an inorganic substrate, the initial peel strength between the heat resistant polymer film and the inorganic substrate, and the peel strength when cooled to room temperature after performing a 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 at 450 ° C. in a nitrogen environment Integer in the range of 1 to 3 Ft [N / cm]: Peel strength after t time of heat treatment ( 2)
A laminate of a heat-resistant polymer film and an inorganic substrate, wherein 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 at 510 ° C. in a nitrogen environment Integer in the range of 1-3 Fs [N / cm]: Peel strength after heat treatment s time

In the present invention, the above (1) and (2) may be satisfied independently, or both may be satisfied. In the present invention, preferably, the following (3) may be made independent or compatible with one or both of (1) and (2).
(3)
A laminate of a heat-resistant polymer film and an inorganic substrate, wherein 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 Integer in the range of 1 to 3 Fu [N / cm]: Peel strength after heat treatment u time

  In the present invention, the portion where the thin film layer of the present invention is formed is divided in a pattern to form a region where the polymer film can be easily separated from the inorganic substrate and an easily peelable portion which cannot be easily separated. Good adhesion portions can be formed. When patterning is performed in this way, the easy peeling part can be easily peeled from the substrate by making a cut along the edge of the pattern from the surface on which the polymer film is laminated. That is, the part satisfying the requirements of the present invention is the easy peeling part.

<Thin film patterning>
The thin film layer can be patterned by a general masking method, a general method such as an etching method using a resist after a thin film is formed on the front surface, or a lift-off method. The pattern shape may be appropriately set according to the type of device to be stacked, and is not particularly limited. The required device shape may be a pattern that is tiled on a plane singly or in a multifaceted manner.

The peel strength between the inorganic substrate and the polymer film in the good adhesion portion is at least twice the peel strength between the inorganic substrate and the polymer film in the easy peel portion, preferably 3 times or more, more preferably 5 It is more than double. The intensity ratio is preferably not less than the above multiple and not more than 100 times, more preferably not more than 50 times. In addition, the measuring method of peeling strength is mentioned later.
When the peel strength between the inorganic substrate and the polymer film in the good adhesion portion is less than twice the peel strength between the inorganic substrate and the polymer film in the easy peel portion, when peeling the polymer film from the inorganic substrate, It is difficult to peel the device forming portion with low stress using the difference in peel strength between the good adhesion portion and the easy peel portion, and the yield of the flexible electronic device may be reduced. On the other hand, if the difference in peel strength between the good adhesion part and the easy peel part is too large, the easy peel part may peel from the inorganic substrate, or the easy peel part may cause uki, blister (blowing of the coating film), etc. There is a case.
The peel strength of the good adhesion part is preferably 0.8 N / cm or more, more preferably 1.5 N / cm or more, still more preferably 2.4 N / cm or more, and most preferably 3.2 N / cm or more. .

  In the present invention, the peel strength of the easy peel portion described above is preferably kept sufficiently low even after heat treatment at 500 ° C. for 10 minutes. By satisfying such conditions, good easy 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.

<Method for manufacturing 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, so that the flexible film is flexible. An electronic device can be fabricated.
The electronic device in the present invention refers to an electronic circuit including a single-sided, double-sided, or multi-layered wiring board that carries electrical wiring, active elements such as transistors and diodes, and passive devices such as resistors, capacitors, and inductors, pressure Sensor elements for sensing temperature, light, humidity, etc., biosensor elements, light emitting elements, liquid crystal displays, electrophoretic displays, self-luminous display image display elements, wireless, wired communication elements, arithmetic elements, memory elements, MEMS It refers to an element, a solar cell, a thin film transistor, and the like.

In the method for producing a device structure of the present invention, after forming a device on the polymer film of the laminate produced by the above-described method, the polymer film at the easy peelable portion of the laminate is cut to form the device. The polymer film is peeled from the inorganic substrate.
As a method of cutting the polymer film of the easy peelable part of the laminate, a method of cutting the polymer film with a cutting tool such as a blade, or a method of cutting the polymer film by relatively scanning the laser and the laminate. There are a method of cutting, a method of cutting a polymer film by relatively scanning a water jet and a laminate, a method of cutting a polymer film while cutting slightly to a glass layer by a semiconductor chip dicing device, etc. The method is not limited. For example, in adopting the above-described method, it is possible to appropriately employ a technique such as superimposing ultrasonic waves on the cutting tool or adding a reciprocating operation or an up-and-down operation to improve the cutting performance.

The method of peeling the polymer film with the device from the inorganic substrate is not particularly limited. However, the method of rolling the film from the end with tweezers, etc., and sticking the adhesive tape to one side of the cut portion of the polymer film, the tape part It is possible to employ a method of winding from a part, a method of winding from one side of a cut portion of the polymer film after vacuum suction, and the like. In addition, when a small curvature occurs in the cut portion of the polymer film during peeling, stress may be applied to the device in that portion and the device may be destroyed. Is desirable. For example, it is desirable to roll while winding on a roll having a large curvature, or to roll using a machine having a configuration in which the roll having a large curvature is located at the peeling portion.
In addition, a method in which another reinforcing base material is attached in advance to the part to be peeled and the whole reinforcing base material is peeled off is also useful. When the flexible electronic device to be peeled off is the backplane of the display device, it is also possible to obtain a flexible display device by pasting the front plane of the display device in advance and integrating them on the inorganic substrate before peeling them off at the same time. is there.

<Recycling of inorganic substrates>
In the polymer film laminated substrate of the present invention, after peeling the electronic device, the polymer film remaining from the polymer film laminated substrate is completely removed, and the inorganic substrate is reused by performing a simple cleaning process, etc. can do. This is because the adhesive force between the thin film and the silane coupling agent layer in the easy-peeling part is uniform and stable, and the polymer film layer can be smoothly peeled off, leaving almost no peeling residue on the inorganic substrate side. by. This is presumably because the peeling surface when peeling the polymer film becomes the thin film surface (interface between the thin film and the silane coupling agent layer). For this reason, after peeling a polymer film, the state by which the thin film was formed in the inorganic substrate (henceforth an inorganic substrate of this state is called thin film lamination inorganic substrate) is maintained.

The present invention will be described more specifically with reference to the following examples. However, the present invention is not limited to the following examples, and may be appropriately modified and implemented within a range that can meet the purpose described above and below. All of which are within the scope of the present invention.
The physical property evaluation methods in the following examples are as follows.

<Reduced viscosity of polyamic acid solution>
A 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 FineLuf).

<Thickness unevenness of polymer film>
Ten thicknesses of the polymer film were obtained by randomly extracting 10 points from the film to be measured using a micrometer ("Millitron 1245D" manufactured by Finelfu) and measuring the film thickness. From the maximum value (maximum film thickness), the minimum value (minimum film thickness), and the average value (average film thickness), the following values were calculated.
Film thickness variation (%) = 100 × (maximum film thickness−minimum film thickness) ÷ average film thickness

<Tensile 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) each of 100 mm × 10 mm was cut out from a polymer film to be measured, and a tensile tester (manufactured by Shimadzu Corporation “Autograph (registered) (Trademark); model name AG-5000A "), tensile modulus, tensile breaking strength and tensile breaking elongation were measured in each of the MD direction and the TD direction under the conditions of a tensile speed of 50 mm / min and a chuck distance of 40 mm. .

<Linear expansion coefficient (CTE) of polymer film>
About the flow direction (MD direction) and the width direction (TD direction) of the polymer film to be measured, the stretch rate is measured under the following conditions, and the intervals of 15 ° C. (30 ° C. to 45 ° C., 45 ° C. to 60 ° C., )) Was measured, and this measurement was performed up to 500 ° C., and an average value of all measured values measured in the MD direction and the TD direction was calculated as a linear expansion coefficient (CTE).
Device name: “TMA4000S” manufactured by MAC Science
Sample length; 20mm
Sample width: 2 mm
Temperature rising start temperature: 30 ° C
Temperature rise end temperature: 500 ° C
Temperature increase rate: 5 ° C./min Atmosphere: Argon initial load: 34.5 g / mm 2

<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 / dissipation due to the structural change 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 stacked on different surfaces (that is, not on the same surface but on the wound outer surface and the wound inner surface when wound as a film roll), and the stacked polymer films are stacked with the thumb and forefinger When sandwiched and rubbed lightly, the case where the polymer film slipped was evaluated as “◯” or “good”, and the case where it did not slip was evaluated as “x” or “bad”. In addition, although it may not slip on winding outer surfaces or between winding inner surfaces, this is not made into 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 applying and drying a silane coupling agent on a separately cleaned Si wafer by the same method as in each example and comparative example was prepared. The film 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 Photo) under the following conditions.
Reflection angle range: 45 ° to 80 °
Wavelength range: 250 nm to 800 nm
Wavelength resolution: 1.25 nm
Spot diameter: 1mm
tan Ψ; Measurement accuracy ± 0.01
cosΔ; Measurement accuracy ± 0.01
Measurement: Method Rotating analyzer method Deflector angle: 45 °
Incident angle: 70 ° fixed Analyzer: 0-360 ° in 11.25 ° increments
Wavelength: 250 nm to 800 nm
The film thickness was calculated by fitting by a non-linear least square method. At this time, the model is Air / thin film / Si,
n = C3 / λ4 + C2 / λ2 + C1
k = C6 / λ4 + C5 / λ2 + C4
The wavelength dependence C1 to C6 was determined by the following formula.

<Peel 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 manufactured, and in a nitrogen-substituted inert oven at 450 ° C. for 1 hour, 2 hours and 3 hours, 510 ° C. for 1 hour, 2 hours and 3 hours, 530 ° C. 1 hour, 2 hours and 3 hours after the heat treatment.

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

<Manufacture of polyimide film>
[Production Example 1]
(Preparation of polyamic acid solution)
After the inside of the reaction vessel equipped with a nitrogen introduction tube, a thermometer, and a stirring rod was purged with nitrogen, 398 parts by mass of 3,3 ′, 4,4′-biphenyltetracarboxylic dianhydride (BPDA) and paraphenylenediamine ( (PDA) 147 parts by mass is dissolved in 4600 parts by mass of N, N-dimethylacetamide, and a dispersion obtained by dispersing colloidal silica as a lubricant in dimethylacetamide (“Snowtex (registered trademark)” manufactured by Nissan Chemical Industries, Ltd. ) DMAC-ST30 ”) was added so that the silica (lubricant) was 0.15% by mass with respect to 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. A brown and viscous polyamic acid solution V1 having a reduced viscosity as shown in FIG.

(Preparation of polyimide film)
The polyamic acid solution V1 obtained above was applied to the final film thickness (imide) on the smooth surface (non-sliding material surface) of a long polyester film (“A-4100” manufactured by Toyobo Co., Ltd.) having a width of 1050 mm using a slit die. The film thickness after conversion was 25 μm, dried at 105 ° C. for 20 minutes, and then peeled 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 heated stepwise by a pin tenter in a temperature range of 150 ° C. to 420 ° C. (first stage 180 ° C. × 5 minutes, second stage 270 ° C. × 10 minutes, (Third stage 420 ° C. × 5 minutes) Heat treatment was performed to imidize, and pin grip portions at both ends were dropped with a slit to obtain a long polyimide film F1 (1000 m roll) having a width of 850 mm. Table 1 shows the characteristics of the obtained film F1.

[Production Example 2]
(Preparation of polyamic acid solution)
After the inside of the reaction vessel equipped with a nitrogen introduction tube, a thermometer, and a stirring rod was purged with nitrogen, 223 parts by mass of 5-amino-2- (p-aminophenyl) benzoxazole (DAMBO), N, N-dimethylacetamide 4416 Next, the colloidal silica dispersion is mixed with 217 parts by mass of pyromellitic dianhydride (PMDA) and the colloidal silica dispersion as a lubricant is polymer solids in the polyamic acid solution. It added so that it might become 0.12 mass% with respect to the total amount, and it stirred for 24 hours at 25 degreeC reaction temperature, and obtained the brown and viscous polyamic-acid solution V2 which has the reduced 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 raised stepwise in a temperature range of 150 ° C. to 485 ° C. with a pin tenter (first stage 150 ° C. × 5 minutes, 2 minutes Except for the stage 220 ° C. × 5 minutes, the third stage 485 ° C. × 10 minutes), the same operation as in Production Example 1 was performed to obtain a long polyimide film F2 (1000 m roll) having a width of 850 mm. Table 1 shows the characteristics of the obtained film F2.
[Production Example 3]
(Preparation of polyamic acid solution)
The same procedure as in Production Example 2 was carried out except that the colloidal silica dispersion was not added to obtain a polyamic acid solution V3.

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

<Plasma treatment of film>
The polyimide film was cut into 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 RF plasma processing are adopted, nitrogen gas is introduced into the vacuum chamber, high frequency power of 13.54 MHz is introduced, and the processing time is 3 minutes.

In the case of an inorganic plate or a multilayer thin film as a base material, an inorganic substrate on which a separate thin film was formed was used as the base material, and the following thin film formation was performed.

<Metal thin film formation example 1>
The inorganic substrate was ultrasonically cleaned with ultrapure and sufficiently dried with dry air through a HEPA filter. Next, the dried inorganic substrate is set in a chamber of a magnetron sputtering apparatus having a gas introduction mechanism and a shutter, and an inorganic substrate is formed with an aluminum mask having a plurality of openings of 50 mm × 80 mm and having a space of 12 mm between the openings. The surface was masked, argon gas was introduced into the chamber so as to be 5 mTorr, sputtering was performed by applying DC power for 10 seconds using a metal molybdenum target, and a molybdenum thin film was formed on the inorganic substrate surface.
In addition, it was 582 nm when the film thickness of the aluminum thin film obtained by carrying out sputtering for 600 second beforehand on the same conditions was measured with the stylus type level difference meter. Since the relationship between the sputtering time and the deposition rate is known to be almost linear, the thickness of the molybdenum thin film obtained in 10 seconds was estimated to be 9.7 nm by proportional calculation.

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

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

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

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

<Example of formation of aluminum oxide film>
The substrate was ultrasonically cleaned with ultrapure and thoroughly dried with dry air through a HEPA filter. Next, the dried base material is set in a chamber of a magnetron sputtering apparatus having a gas introduction mechanism and a shutter, and the base material is made of an aluminum mask having a plurality of openings of 50 mm × 80 mm and having a distance of 12 mm between the openings. The surface was masked, argon gas was introduced into the chamber at 15 mTorr, and a metal aluminum target was used to perform magnetron sputtering with 13.54 MHz RF power application for 5 seconds to form an aluminum thin film on the substrate surface. .
In addition, it was 405 nm when the film thickness of the aluminum thin film obtained by performing sputtering for 120 seconds beforehand on the same conditions was measured with the stylus type level difference meter. Since the relationship between the sputtering time and the deposition rate is known to be almost linear, the thickness of the aluminum thin film obtained in 5 seconds was estimated to be 16.9 nm by proportional calculation.
Next, after forming the aluminum thin film, the inside of the chamber is replaced with oxygen gas, and in the state where the oxygen gas is flowed 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. Formed.

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

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

<Aluminum nitride>
A 150 nm thick aluminum nitride thin film was formed by reactive sputtering.

<Example of formation of composite oxide film of aluminum and silicon>
In the example of forming the composite oxide film of aluminum and silicon, a 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 composite oxide of aluminum and silicon having a ratio of aluminum to silicon of 37:63 (element ratio) was obtained.
In addition, a thin film deposition experiment for 600 seconds was performed in advance, and the thickness was measured with a stylus type step gauge. As a result, it was 1134 nm, so the deposited 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 thin film formation as a base material.

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

<Example 1>
<Production of laminate and evaluation of initial characteristics>
A soda glass having a thickness of 370 mm × 470 mm and a thickness of 1.1 mm was used as the inorganic substrate, and a molybdenum thin film was formed according to the above-described formation example. Further, a silane coupling agent treatment was performed on the thin film layer side by spin coating.
Next, the film was cut into 380 mm × 480 mm and temporarily laminated using a laminator (SE650nH manufactured by Climb Products Co., Ltd.) so that the plasma-treated surface of the polyimide film F1 subjected to plasma treatment overlapped with the silane coupling agent-treated surface of the inorganic substrate. . Lamination conditions were an inorganic substrate temperature of 100 ° C., a roll pressure of 5 kg / cm 2 during lamination, and a roll speed of 5 mm / second. The polyimide film after temporary lamination did not peel off due to its own weight, but had such adhesiveness that it was easily peeled off when the film edge was scratched. Thereafter, the obtained temporary laminated laminated substrate was put 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 multilayer substrate. Here, the easy peeling portion is a portion where the composite oxide thin film layer of aluminum and silicon is formed, and the good adhesion portion is a portion where the thin film layer is not formed by masking.

  Hereinafter, similarly to Example 1, a laminate was prepared by appropriately changing conditions such as inorganic substrate, thin film formation method, polyimide film, silane coupling agent coating method, presence / absence of plasma treatment of polyimide film, and properties were evaluated. . The results are shown in Table 2, Table 3, and Table 4.

In the table, “glass” was 370 mm × 470 mm, soda glass having a thickness of 1.1 mm, and “Si wafer” was 8 inches, and a silicon single crystal wafer having a thickness of 0.7 mm was used. The “F3 non-smooth surface” is the side of the film F3 that uses the polyamic acid V3.
Also, 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 array having a bottom gate type structure on a polyimide film was prepared on an 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 using 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 5 nm Cr layer and a 40 nm gold layer were formed by sputtering, and a source electrode and a drain electrode were formed by photolithography. In addition, using a slit die coater, an epoxy resin that becomes an insulating layer / dam layer is applied, and a 250-nm thick dam layer 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 forming a connection point with the upper electrode was simultaneously formed. Then, polythiophene, which is an organic semiconductor, was coated in the dam by an ink jet printing method, a silver paste was embedded in the via portion, and an aluminum wiring was formed as an upper electrode to form a thin film transistor array having 640 × 480 pixels.
The obtained thin film transistor array was used as a back plane, and an electrophoretic display medium was overlaid on the front plane to form a display element. The yield and display performance of the transistor were determined by ON / OFF of each pixel. As a result, the display performance was good in the thin film transistor array produced using any laminate.
In addition, after superimposing the front plane on the thin film transistor array, the polymer film part is burned off with a UV-YAG laser along the inner side of the thin film pattern about 0.5 mm, and a thin razor blade is used from the edge of the cut. Stripping was performed to scoop up to obtain a flexible electrophoretic display. The obtained electrophoretic display showed good display characteristics, and no performance deterioration was observed even when it was wound around a 5 mmφ round bar.

<Application example 2>
After peeling the flexible electrophoretic display device in Application Example 1, the inorganic substrate was immersed in a 10% aqueous sodium hydroxide solution at room temperature for 20 hours. Thereafter, it was washed with water, further cleaned with a glass cleaning device for liquid crystal substrates, and after drying, UV ozone cleaning was performed for 3 minutes. Thereafter, the process returns to the above-described <Formation of Silane Coupling Agent Layer on Inorganic Substrate>, and the subsequent steps were performed by the same production method as that for producing the laminate first, thereby obtaining a laminate. The quality of the obtained laminate was good, and it was sufficiently recyclable.

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

  Next, a laminated board with a base metal thin film forming film from each film is fixed to a Cu frame, and an electroplating solution (copper sulfate 80 g / l, sulfuric acid 210 g / l, HCl, gloss, 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 flowing 1.5 A / dm 2 of electricity. Then, it heat-processed for 10 minutes at 120 degreeC, it dried, and the copper foil layer was formed in the polymer film surface of a laminated body.

After applying and drying a photoresist (“FR-200” manufactured by Shipley Co., Ltd.) on each of the obtained copper foil layers, it was subjected to off-contact exposure 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 40 ° C. and a spray pressure of 2 kgf / cm 2 to form a line array of lines / spaces = 20 μm / 20 μm as a test pattern. Next, after electroless tin plating was performed to a thickness of 0.5 μm, 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 the test pattern. As a result, there was no disconnection or short circuit in the wiring pattern, and the pattern shape was good. Subsequently, the polymer film was peeled 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 (film thickness 75 nm) was formed on a polyimide film by vacuum deposition using the following steps, and further oxidized as an insulating film without exposure to the atmosphere. A silicon film (thickness 150 nm) was stacked. Next, a silicon oxynitride film (film thickness: 100 nm) serving as a base insulating film was formed by a plasma CVD method, and an amorphous silicon film (film thickness: 54 nm) was stacked without being exposed to the atmosphere.

Next, the hydrogen element in the amorphous silicon film was removed to promote crystallization, and a heat treatment at 500 ° C. was performed for 40 minutes in order to form a polysilicon film.
A TFT element was fabricated using a portion in the easily peelable portion of the obtained polysilicon film. First, a polysilicon thin film is patterned to form a silicon region having a predetermined shape, and 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, an interlayer insulating film , Formation of source and drain electrodes, and activation treatment were performed to fabricate an array of P-channel TFTs using polysilicon.
The polymer film part is burned out with a UV-YAG laser along the inner side of the TFT array around 0.5 mm, and then peeled off from the edge of the cut using a thin razor blade to create a flexible TFT array. Obtained. Peeling was possible with extremely little force, and peeling was possible without damaging the TFT. Even when the obtained flexible TFT array was wound around a 3 mmφ round bar, no performance deterioration was observed, and good characteristics were maintained.

  The easy peeling part of the polymer film laminated substrate of the present invention is to 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. In addition, since the good adhesion portion stably adheres the film and the inorganic substrate during various steps of device manufacturing, problems such as peeling during the steps do not occur. Even when the peeled inorganic substrate is recycled, the polyimide film on which the electronic device is mounted can be easily peeled off from the inorganic substrate as before recycling, which is particularly useful for the production of flexible electronic devices. And the contribution to the industry is great.

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

Claims (10)

A laminate of a heat resistant polymer film and an inorganic substrate, the initial peel strength between the heat resistant polymer film and the inorganic substrate, and the peel strength when cooled to room temperature after performing a 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 at 450 ° C. in a nitrogen environment Ft [N / cm]: Peel strength after heat treatment t time A laminate of a heat-resistant polymer film and an inorganic substrate, wherein 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 at 510 ° C. in a nitrogen environment Integer in the range of 1-3 Fs [N / cm]: Peel strength after heat treatment s time   The laminate according to claim 1, further comprising a silane coupling agent layer between the heat resistant polymer film and the inorganic substrate.   The laminate according to any one of claims 1 to 3, wherein 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.   The laminate according to any one of claims 1 to 4, further comprising an aluminum oxide layer between the silane coupling agent layer and the inorganic substrate.   The laminate according to any one of claims 1 to 4, wherein a silicon compound layer is provided between the silane coupling agent layer and the inorganic substrate.   The laminate according to any one of claims 1 to 4, wherein a composite oxide layer of aluminum and silicon is provided between the silane coupling agent layer and the inorganic substrate.   At least one or more selected from 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 between the silane coupling agent layer and the inorganic substrate The thin film layer containing a material, and the thin film layer containing at least one material selected from molybdenum, tungsten, chromium, and nickel-chromium alloy on the side in contact with the inorganic substrate. The laminated body in any one.   Between the silane coupling agent layer and the inorganic substrate, at least the 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, chromium, nickel on the side in contact with the inorganic substrate. It has a metal thin film containing the 1 type selected from a ruchrome alloy, The laminated body in any one of Claim 1 to 3 characterized by the above-mentioned.   The laminate according to any one of claims 1 to 9, wherein the laminate is used as a temporary support substrate for forming an electronic device.