Method for removing a fluoropolymer lift-off layer - Patents.com

Abstract

The present invention relates to a method for removing a layer of lift-off fluoropolymer from a substrate using a particular stripping solvent, particularly in the manufacture of OLED devices, and to a lithography process using said combination of lift-off fluoropolymer and stripping solvent.

Description

[Technical field]

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS This application claims priority to earlier European Patent Application No. 19215451.6, filed December 12, 2019, the entire contents of which are incorporated herein by reference for all purposes.

[0002] The present invention relates to a method for removing a layer of a lift-off fluoropolymer from a substrate using a specific stripping solvent, and to a lithography process using said combination of a lift-off fluoropolymer and a stripping solvent. [Background technology]

[0003] Fluoropolymers have already been used in the past in lithographic processes, more specifically as protective layers in certain photolithographic methods, however, the creation of a sacrificial fluoropolymer layer is necessary to protect / maintain the chemical integrity of the substrate during either the radiation exposure of the photoresist and / or the etching of the photoresist layer.

[0004] The document U.S. Pat. No. 9,899,636 discloses a method for making an OLED device, comprising: a) providing a device substrate having a first array of bottom electrodes and a second array of bottom electrodes; b) providing a first undercut lift-off structure over the device substrate having a first pattern of openings corresponding to the first array of bottom electrodes; c) depositing one or more first organic EL media layers including at least a first light-emitting layer over the first undercut lift-off structures and over the first array of bottom electrodes; d) treating with a first lift-off agent comprising a fluorinated solvent to remove the first undercut lift-off structure and the overlying first organic EL medium layer to form a first intermediate structure; e) providing a second undercut lift-off structure over the first intermediate structure having a second pattern of openings corresponding to a second array of bottom electrodes; f) depositing one or more second organic EL media layers including at least a second light-emitting layer over the second undercut lift-off structures and over the second array of bottom electrodes; g) treating with a second lift-off agent comprising a fluorinated solvent to remove the second undercut lift-off structure and the overlying second organic EL medium layer to form a second intermediate structure; and h) providing a common top electrode in electrical contact with the first and second organic EL media layers;

[0005] The undercut lift-off structure includes a base layer of a fluorinated material and an overlying photoresist layer developed using a fluorinated solvent selected from those that are perfluorinated or highly fluorinated liquids at room temperature that are immiscible with water and many organic solvents. Among these solvents, hydrofluoroethers (HFEs), including segregated HFEs, are recommended as the preferred solvents because they are non-flammable, have zero ozone depletion potential, lower global warming potential than PFCs, and have very low toxicity to humans.

[0006] Similarly, US Patent No. 9,768,384 discloses a method for manufacturing an organic light-emitting display device, comprising forming a lift-off layer comprising a fluoropolymer on a substrate, forming a photoresist on the lift-off layer and removing a portion thereof, etching the lift-off layer in the areas where the photoresist is removed using a first solvent such that a portion of the lift-off layer remains on the substrate, forming an organic light-emitting layer as an etch stop layer on the lift-off layer remaining on the substrate and on the areas where the photoresist remains on the lift-off layer, and patterning the photoresist by removing the lift-off layer under the areas where the photoresist remains on the lift-off layer using a second solvent. The fluoropolymer may comprise at least one of polytetrafluoroethylene, polychlorotrifluoroethylene, polydichlorodifluoroethylene, copolymers of chlorotrifluoroethylene and dichlorodifluoroethylene, copolymers of tetrafluoroethylene and perfluoroalkylvinylethers, copolymers of chlorotrifluoroethylene and perfluoroalkylvinylethers, copolymers of tetrafluoroethylene and perfluoroalkylvinylethers, and copolymers of chlorotrifluoroethylene and perfluoroalkylvinylethers. The first and second solvents contain fluorine and are typically hydrofluoroethers such as 3M NOVEC® 7100, 7300, and 7500.

[0007] In a similar manner, U.S. Pat. No. 9,091,913 discloses a method for producing spatially patterned structures on a substrate, comprising the steps of: (1) forming a layer of material on at least a portion of the substructure of the spatially patterned structure; (2) forming a barrier layer of a fluorinated material on said layer of material to provide an intermediate structure; (3) forming a layer of photoresist on the barrier layer; (4) exposing the photoresist to spatially patterned radiation; (5) developing the photoresist to substantially remove one of the exposed or unexposed areas of the photoresist to provide a pattern of uncovered areas of barrier material between areas covered by photoresist; (6) removing portions of the barrier material not covered by the photoresist to provide a pattern of uncovered areas of the layer of material; (7) exposing the intermediate structure to at least one of a second material or radiation to cause at least one of a chemical change or a structural change in at least a portion of the intermediate structure; and (8) removing the remaining portion of the barrier layer using a fluorinated solvent, in which the barrier layer of fluorinated material substantially protects the layer of material from chemical and structural changes during the formation of the layer of the photoresist and the exposure of the photoresist. The fluorinated material may be a fluorinated polymer, such as the materials known under the brand names CYTOP® or TEFLON®-AF, which are known in particular to contain alicyclic structures in the backbone, or may be a fluorinated polymer of formula C n F (2n+2) The fluoropolymer barrier layer may be a fluorinated compound of CF2, and the document specifically teaches that -COOH compounds (carboxylic acids) may not be suitable, since the -COOH group significantly alters solubility, although the document acknowledges that the presence of other chemical moieties besides CF2 may be tolerated. Solvents used for removal of such fluoropolymer barrier layers include perfluorodecalin, perfluoro(1,2- or 1,3-dimethylcyclohexane, perfluorokerosene, perfluoro(methyldecalin), perfluoroheptane mixed isomers, and more generally volatile fluorinated solvents. The method of this document can be used to create diode junctions.

[0008] Nonetheless, in this field, for a method involving removing a lift-off layer made from a fluorinated polymer to be particularly adapted for use in an OLED lithography process, the removal must comply with certain manifold requirements: it must remain substantially unmodified without swelling or adsorption of the stripping solvent by the underlying layers, including, for example, the electron transport layer or the emissive layer, and it must provide for rapid, effective and thorough removal of the fluorinated polymer from the same layer without compromising the emissive performance of the emissive layer due to fluorinated residues.

[0009] While certain materials such as CYTOP® or TEFLON®-AF have been tested in this field of use and have been removed with fluorosolvents such as hydrofluoroethers, there remains a need in the field to provide improved methods for removing lift-off / protective layers made of fluorinated polymers from substrates. Summary of the Invention

[0010] Therefore, a first object of the present invention is to - a repeat unit having an alicyclic structure in the main chain of the fluoropolymer and derived from at least one fluoromonomer A; Optionally, - repeat units derived from at least one fluoromonomer B different from fluoromonomer A; A composition comprising at least one fluoropolymer (C LO ) The fluoropolymer is: - having an intrinsic viscosity of less than 30 cc / g, measured at 30°C in perfluorohexane as a solvent; - containing an amount of carboxylic acid end groups less than 8 mmol / kg a method for at least partially removing a lift-off layer [layer (LO)] made from The method comprises: - providing an assembly comprising a support material having an area covered with a layer (LO); to obtain at least a partial removal of said layer (LO), a) 15.0 MPa 1 / 2 Hansen solubility parameter δ less than T At least one fluorinated solvent [solvent (F)] having the formula b) 10 to 10,000 ppm based on the weight of the solvent (F), of at least one polar organic solvent [solvent (P)] different from the solvent (F) (the solvent (P) has a viscosity of at least 20.0 MPa 1 / 2 and at most 26.0 MPa 1 / 2 Hansen solubility parameter δ T having contacting the assembly with a stripping solvent mixture comprising: Includes.

[0011] The applicant has surprisingly discovered that by (i) carefully selecting a polymer (F) having said alicyclic structure in its main chain, satisfying the above requirements of intrinsic viscosity and carboxylic acid end group content, and (ii) selecting a unique stripping solvent mixture comprising a fluorinated solvent having a low Hansen Solubility Parameter and a small amount of another solvent having a higher Hansen Solubility Parameter, it is possible to achieve effective removal of the lift-off layer without adversely affecting the properties of the substrate or other layers of the assembly. [Brief description of the drawings]

[0012] [Figure 1] 1 is a graph showing normalized emission as a function of time for reference OLED devices constructed without a lift-off layer; device (1) produced in accordance with the present invention with application and removal of a lift-off layer; and a comparative device (2C) not produced in accordance with the method of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0013] Polymer (F) As used herein, the expression "fluoromonomer" should be understood to include monomers having at least one fluorine atom bonded to a carbon atom, which may or may not contain a hydrogen atom bonded to that carbon atom. When a fluoropolymer does not contain any hydrogen atoms bonded to its carbon atoms, the fluoromonomer is called a "perfluorinated monomer."

[0014] As mentioned above, polymer (F) has an alicyclic structure in the main chain of the fluoropolymer and contains repeat units derived from at least one fluoromonomer A. The fluoromonomer A of the polymer (F) of the present invention specifically includes two types of fluoromonomers, namely, fluoromonomers having an alicyclic structure in their monomer form, and fluoromonomers that do not have an alicyclic structure in their monomer form but provide an alicyclic structure in the resulting repeat unit of polymer (F) upon cyclopolymerization.

[0015] Fluoromonomer A is preferably a perfluoromonomer.

[0016] The repeating unit derived from the fluoromonomer A is preferably represented by any one of the following formulas (1) to (3): [ka] (In the formula: In formula (1), p, q, and r are each independently 0 or 1; R f1 and R f2 may be the same or different and are a fluorine atom, a C1-C5 perfluoroalkyl group, or a C1-C5 perfluoroalkoxy group; R f3 is a C1-C3 perfluoroalkylene group, which may have a C1-C5 perfluoroalkyl group or a C1-C5 perfluoroalkoxy group as a substituent; In formula (2), s is 0 or 1, R f4 , R f5 , Rf6 and R f7 may be the same or different and are a fluorine atom or a C1-C5 perfluoroalkyl group; R f8 is a fluorine atom, a C1-C5 perfluoroalkyl group, or a C1-C5 perfluoroalkoxy group, provided that when s=0, R f4 and R f5 can be joined to form a spiro ring, In equation (3), R f9 , R f10 , R f11 and R f12 each of which may be the same or different and is a fluorine atom or a C1-C5 perfluoroalkyl group or a C1-C5 perfluoroalkoxy group.

[0017] The repeat unit structures of formula (1) above can be advantageously derived from fluoromonomers that do not have alicyclic structures in their monomeric form, but which upon cyclopolymerization provide alicyclic structures in the repeat units derived therefrom. As noted above, in formula (1) above, R f3 may have a C1-C5 perfluoroalkyl group or a C1-C5 perfluoroalkoxy group attached as a substituent. Furthermore, in general, in formula (1), when q=o, r=1, and / or, alternatively, when q=1, r=0. Specific examples of repeat units of formula (1) include, in particular, those represented by the following formulas (4)-(19): [ka]

[0018] As described in detail above, among the repeating units of formula (1) above, the repeating unit of formula (4) is preferred.

[0019] The repeat unit of formula (4) is advantageously obtained from the radical cyclopolymerization of perfluoro(3-butenyl vinyl ether) of formula (4A): CF2=CF-O-CF2-CF2-CF=CF2.

[0020] Furthermore, the repeating unit structure of the above formula (2) can be advantageously derived from a fluoromonomer having an alicyclic structure in its monomer structure. Furthermore, in the repeating unit structure of formula (2), when S=0, R f4 and R f5 When the spiro ring formed by is a 4- to 6-membered ring, such a ring may contain an ether oxygen atom as a constituent of the ring, and such a ring may have a perfluoroalkyl group bonded as a substituent.

[0021] Specific examples of repeat units of formula (2) include, inter alia, those represented by the following formulae (20) to (30): [ka]

[0022] As described above in detail, among the repeating units of formula (2), the repeating units of formulas (20), (21) and (26) are preferred. The repeating units of formulas (20), (21) and (26) are advantageously obtained from the radical polymerization of perfluoro(2,2-dimethyl-1,3-dioxole) of formula (20A), perfluoro(1,3-dioxole) of formula (21A) and 2,2,4-trifluoro-5-trifluoromethoxy-1,3-dioxole of formula (26A), respectively: [ka]

[0023] Furthermore, the structure of the repeating unit of the above formula (3) can be advantageously derived from a fluoromonomer having an alicyclic structure in its monomer structure.

[0024] Specific examples of repeat units of formula (3) include, inter alia, those represented by the following formulae (31)-(33): [ka]

[0025] As described above, among the repeating units of formula (3), the repeating unit of formula (31) is preferred. The repeating unit of formula (31) is represented by formula (31A): [ka] It is derived from perfluoro(2-methylene-4-methyl-1,3-dioxolane).

[0026] As mentioned above, polymer (F) may contain repeat units derived from at least one fluoromonomer B different from fluoromonomer A.

[0027] The fluoromonomer B can be selected from the group consisting of: (a) C2-C8 perfluoroolefins such as tetrafluoroethylene (TFE) and hexafluoropropylene (HFP); (b) Vinylidene fluoride (VDF), vinyl fluoride, trifluoroethylene (TrFE), hexafluoroisobutylene (HFIB), formula CH2=CH-R f1 (In the formula, R f1 is a C1-C6 perfluoroalkyl group), (c) C2-C8 chloro- and / or bromo-containing fluoroolefins such as chlorotrifluoroethylene (CTFE); (d) Formula CF2=CFOR f1 (In the formula, R f1 perfluoroalkyl vinyl ethers (PAVEs) of which C1 to C6 perfluoroalkyl groups such as CF3 (PMVE), C2F5 or C3F7; (e) In particular, the formula CF2 = CFOCF2OR f2 (R f2 perfluoromethoxyalkyl vinyl ethers of the formula CF2=CFOX0 (wherein X0 is a C1-C3 perfluoro(oxy)alkyl group containing one or more ethereal oxygen atoms), such as -CF2CF3, -CF2CF2-O-CF3, and -CF3. 12perfluorooxyalkyl vinyl ethers, (f) a compound of the formula CF2=CFOY0, where Y0 is a C1-C12 perfluoro(oxy)alkylene group, optionally containing one or more ethereal oxygen atoms, and containing at least one functional group selected from the group consisting of SO2X, -COX, and -PO2X, where X is a halogen or -OX a is a group, X a is H, an ammonium group, or a metal cation).

[0028] Fluoromonomer B is preferably a perfluoromonomer, more preferably selected from the group consisting of C2 to C8 perfluoroolefins, and most preferably fluoromonomer B is tetrafluoroethylene (TFE).

[0029] The polymer (F) may contain repeat units derived from monomers different from fluoromonomer A and fluoromonomer B, in particular the polymer (F) may contain repeat units derived from fluorine-free monomers such as α-olefins (e.g. ethylene, propylene, butene, hexene), vinyl monomers (e.g. optionally substituted styrene-type monomers, (meth)acrylic monomers). Nevertheless, it is generally preferred that the polymer (F) essentially consists of fully fluorinated, i.e. monomers that do not contain CH moieties. Small amounts (e.g. less than 1 mol %, preferably less than 0.1 mol %, based on the total moles of repeat units) of repeat units derived from hydrogen-containing monomers can be tolerated without this significantly affecting the performance of the polymer (F). According to these embodiments, the polymer (F) preferably essentially consists of: - a repeat unit derived from at least one perfluorinated fluoromonomer A having an alicyclic structure in the main chain of the fluoropolymer, optionally - a repeat unit derived from at least one perfluorinated fluoromonomer B different from fluoromonomer A;

[0030] The polymer (F) is advantageously an amorphous polymer. The term "amorphous" is used herein in relation to the polymer (F) to denote a polymer having a heat of fusion of less than 5 J / g, preferably less than 3 J / g, more preferably less than 2 J / g, determined according to ASTM D3418.

[0031] As mentioned above, according to the first variant of the present invention, polymer (F) can be a homopolymer having an alicyclic structure in the main chain of said fluoropolymer and essentially consisting of repeating units derived from a perfluorinated fluoromonomer A. A homopolymer consisting of repeating units derived from a fluoromonomer A selected from the group consisting of perfluoro(2-methylene-4-methyl-1,3-dioxolane), perfluoro(2,2-dimethyl-1,3-dioxole), perfluoro(1,3-dioxole), 2,2,4-trifluoro-5-trifluoromethoxy-1,3-dioxole and perfluoro(3-butenyl vinyl ether) is an exemplary preferred embodiment of polymer (F) according to this variant of the present invention.

[0032] As detailed above, due to their structure, it is understood that the repeat units derived from fluoromonomer A having an alicyclic structure in the main chain of the fluoropolymer generally result in a homopolymer that is substantially amorphous.

[0033] According to another variant of the invention, polymer (F) may contain repeat units derived from at least one fluoromonomer B, which may or may not contribute to the formation of crystalline domains of polymer (F).

[0034] Nevertheless, in general, as detailed above, when polymer (F) comprises repeat units derived from at least one fluoromonomer B, the respective amounts of repeat units derived from fluoromonomer A and fluoromonomer B are adjusted so that polymer (F) is substantially amorphous. According to these embodiments, polymer (F) is - 20 to 95 mol %, preferably 30 to 80 mol %, more preferably 35 to 50 mol %, of repeating units having an alicyclic structure in the main chain of the fluoropolymer and derived from at least one fluoromonomer A, based on the total moles of repeating units of polymer (F), as described above in detail; - as described in detail above, comprises (preferably consists essentially of) 5 to 80 mol %, preferably 20 to 70 mol %, more preferably 50 to 65 mol %, of repeat units derived from at least one fluoromonomer B different from fluoromonomer A, based on the total moles of repeat units of polymer (F).

[0035] When used in connection with polymer (F) and its constituent repeat units, the expression "consisting essentially of" should be understood to mean that in addition to the indicated repeat units, defects, end chains, impurities, chain inversions or branches, etc. may further be present in polymer (F), without these components substantially altering the behavior and properties of polymer (F).

[0036] According to a particularly preferred embodiment of this variant, the polymer (F) is - repeat units derived from at least one perfluorinated fluoromonomer A having an alicyclic structure in the main chain of the fluoropolymer, as detailed above; - a copolymer comprising repeat units derived from at least one fluoromonomer B which is perfluorinated and different from fluoromonomer A, as detailed above.

[0037] More preferably, the polymer (F) is - repeat units derived from at least one fluoromonomer A selected from the group consisting of perfluoro(2-methylene-4-methyl-1,3-dioxolane), perfluoro(2,2-dimethyl-1,3-dioxole), perfluoro(1,3-dioxole), 2,2,4-trifluoro-5-trifluoromethoxy-1,3-dioxole and perfluoro(3-butenyl vinyl ether); - Repeating units derived from tetrafluoroethylene (TFE) It is a copolymer comprising:

[0038] Most preferably, the polymer (F) is - repeating units derived from 2,2,4-trifluoro-5-trifluoromethoxy-1,3-dioxole; - Repeating units derived from tetrafluoroethylene (TFE) and preferably consisting essentially of:

[0039] The intrinsic viscosity of polymer (F) can be determined using the Solomon-Ciuta equation based on the drop time of a solution of polymer (F) in Fluorinert® FC72 (also known as perfluorohexane) at a concentration of 1 g / dl using an Ubbelhode viscometer at 30° C.

[0040] As stated above, polymer (F) has an intrinsic viscosity, as determined in Fluorinert® FC72 (also known as perfluorohexane) as the solvent at a temperature of 30° C., of less than 30 cc / g, preferably less than 25 cc / g, more preferably less than 20 cc / g.

[0041] Although the lower limit of the intrinsic viscosity is not particularly limited, it is preferred that the polymer (F) has an intrinsic viscosity of at least 5, preferably at least 7, and more preferably at least 10 cc / g, as determined in Fluorinert® FC72 (also known as perfluorohexane) as a solvent at a temperature of 30° C.

[0042] The expression "amount of carboxylic acid end groups" refers to both their acidic form (-COOH), their acyl halide form (-COX x , X x is F, Cl or Br, and generally X x is F), and their carboxylic acid forms (-COOX b , X bis (alkyl)ammonium, or metal cation) in the polymer (F) to include the total amount of carboxylic acid chain ends that may be present. Methods for determining the amount of carboxylic acid end groups in polymer (F) are known, and said amount can be determined according to the methodology described in PIANCA, M., et al. End groups in fluoropolymers. Journal of Fluorine Chemistry. 1999, vol. 95, p. 71-84.

[0043] As mentioned above, polymer (F) comprises an amount of carboxylic acid end groups of at most 8.0 mmol / kg, preferably at most 7.5 mmol / kg, more preferably at most 7.0 mmol / kg, even more preferably at most 6.5 mmol / kg, even more preferably at most 6.0 mmol / kg.

[0044] A low amount of carboxylic acid end groups is not particularly important, for example, a polymer (F) can be used that is substantially free of carboxylic acid end groups, i.e., their amount is below the detection limit of the above-mentioned method. According to other embodiments, a polymer (F) can be used in which a minimal amount of carboxylic acid end groups is present, which can prove to be advantageous in order to provide a particularly advantageous adhesion to the underlying support layer. According to these embodiments, the polymer (F) can have an amount of carboxylic acid end groups that is at least detectable, or even at least 0.5 or even at least 1.0 mmol / kg.

[0045] Adjustment of the viscosity, and thus the molecular weight and carboxylic acid end group concentration, can be achieved during the polymerization to produce polymer (F) by affecting the relative concentration of inorganic peroxide initiators which lead to said polar end groups, and by affecting other polymerization parameters including the concentration of growing chains (which further affects the viscosity), chain transfer agents which not only control the viscosity but also introduce alternative chain terminations, and monomer concentration, pressure, temperature, etc. Additionally, post-treatment methods such as fluorination, depolymerization, irradiation, etc. can be used to further increase or decrease the viscosity and / or modify the nature of the end groups.

[0046] For the purposes of the present invention, the solvent (F) and the solvent (P) are defined by their Hansen total solubility parameters δ T According to Hansen's method, the parameter δ T is divided into three components: polar, dispersive, and hydrogen bonding, where in the following, Eq. 1 is the relationship between the various components and the total solubility parameter δ T It shows the relationship between: δ T 2 = δ D 2 +δ P 2 +δ H 2 (Formula 1)

[0047] Solvents (F) which have been found to be particularly useful in carrying out the process of the present invention are those having the following components: variance component, δ D , 11.0~14.50 polar component, δ P , 0.1 to 5.0 Hydrogen-bonding component, δ H , 0.0~2.0.

[0048] From the structural point of view, the preferred solvent (F) is a hydrofluoroether (HFE), i.e., sp 3 They are ethers that contain partially fluorinated hydrocarbon structures that contain both hydrogen and fluorine atoms bonded to hybridized carbons.

[0049] Examples of readily available HFEs and isomeric mixtures of HFEs include, but are not limited to, an isomeric mixture of methyl nonafluorobutyl ether and methyl nonafluoroisobutyl ether (commercially available, among others, as NOVEC® HFE-7100), an isomeric mixture of ethyl nonafluorobutyl ether and ethyl nonafluoroisobutyl ether (commercially available, among others, as NOVEC® HFE-7200), 3-ethoxy-1,1,1,2,3,4,4,5,5,6,6,6-dodecafluoro-2-trifluoromethyl-hexane (commercially available, among others, as NOVEC® HFE-7500), 1-methoxyheptafluoropropane (commercially available, among others, as NOVEC® HFE-7000), and 1,1,1,2,2,3,4,5,5,5-decafluoro-3-methoxy-4-trifluoromethylpentane (commercially available, among others, as NOVEC® HFE-7300).

[0050] Preferred solvents (F) have a normal boiling point of more than 60°C and at most 130°C, more preferably the normal boiling point of solvent (F) is comprised between 60 and 110°C.

[0051] A solvent (F) which has been found to be particularly effective is 1,1,1,2,2,3,4,5,5,5-decafluoro-3-methoxy-4-trifluoromethylpentane (notably commercially available as NOVEC® HFE-7300).

[0052] According to the solvent (P), the solvent (P) is at most 25.5 MPa 1 / 2 It is preferable that the solubility parameter is δ T But at least 20.0MPa 1 / 2 , and at most 25.5 MPa 1 / 2 Among the solvents (P) in which T =25.1MPa 1 / 2 ), PGME(δ T =21.9MPa 1 / 2 ), cyclohexanol (δ T=22.4MPa 1 / 2 Cyclopentanol is particularly preferred.

[0053] The amount of the solvent (P) is, as described above, 10 to 10,000 ppm, preferably 100 to 1,500 ppm, based on the weight of the solvent (F).

[0054] Composition (C LO The composition (C) comprises at least one polymer (F), i.e. may comprise one or more polymers (F). LO ) does not contain any polymeric components other than the polymer (F), and may contain certain amounts of additives such as viscosity modifiers, stabilizers, antioxidants, UV stabilizers, etc. Nevertheless, it is generally understood that the stability of the polymer (F) is such that the use of additives can generally be avoided. Thus, according to a preferred embodiment, the composition (C LO ) consists essentially of polymer (F), i.e., only a small amount (e.g., composition (C LO Less than 1.0% by weight, preferably less than 0.5% by weight, more preferably less than 0.1% by weight, based on the total weight of the polymer (F), of impurities, additives or other components may be tolerated, provided that their presence does not substantially affect the distinguishing characteristics of the layer (LO) of the polymer (F).

[0055] According to a particular embodiment, the method of the invention is used in a method for producing patterned structures on a substrate, which is another object of the invention.

[0056] A method for producing a patterned structure on a substrate includes: (1) A layer (LO) composition (C) containing a polymer (F) is applied to the substrate. LO ) in at least a portion of the substrate, a composition (C LO ) applying (2) patterning said layer (LO) to obtain a patterned layer (LO) comprising a pattern of covered and uncovered areas; (3) at least partially removing the uncovered areas of the patterned layer (LO) by contacting with a stripping solvent mixture according to the method of the present invention to obtain a patterned structure comprising a pattern of layer (LO) on the substrate; Includes.

[0057] Composition (C LO Step (1) of applying the composition (C) can be carried out according to known coating techniques, including in particular doctor blade coating, metering rod (or Meyer rod) coating, slot die coating, knife over roll coating, gap coating, spin coating, etc., to obtain a wet layer. LO ) onto the substrate, and subsequent at least partial removal of the liquid medium will advantageously result in the lift-off layer on the substrate, as detailed above. According to these embodiments, the polymer (F) may be solubilized or dispersed in a liquid medium prior to step (1), and thus step (1) may comprise a step of removing the liquid medium. According to these embodiments, the liquid medium generally comprises at least one organic solvent. The organic solvent may be selected from the group consisting of organic solvents containing at least one fluorine atom, including in particular perfluoroalkanes, perfluoroethers, hydrofluoroethers, fluoroamines, perfluoroamines, fluorocyclic organic compounds or mixtures thereof. In connection with the solvent (F) as described above, HFE may be used. In order to minimize the number of different liquid media used in the method, the liquid medium may be the same as the stripping solvent mixture. If the liquid medium is the same as the stripping solvent mixture, the liquid medium is generally removed and recovered by evaporation.

[0058] Step (2) comprises patterning said layer (LO) to obtain a patterned layer (LO) comprising a pattern of covered and uncovered areas. The method for achieving said patterning is not particularly limited. According to a preferred embodiment, step (2) comprises: a substep (2A) of forming a layer of photoresist on said layer (LO) to obtain a photoresist layer; a substep (2B) of exposing said photoresist layer to patterned radiation to obtain a patterned photoresist layer comprising radiation-modified and non-radiation-modified regions; a substep (2C) of substantially removing either the radiation-modified or non-radiation-modified regions to obtain a patterned layer (LO) comprising a pattern of photoresist-covered and non-photoresist-covered regions; Includes.

[0059] The choice of photoresist is not particularly limited. Photoresists well known in the art can be used, including positive and negative photoresists, i.e. photoresists in which exposure to radiation makes the same more easily removable, e.g. more soluble (so-called "positive" photoresists), and photoresists in which exposure to radiation makes the same less removable, e.g. less soluble, for example, by crosslinking / polymerization (so-called "negative" photoresists).

[0060] The step (2B) of exposing the photoresist to patterned radiation can be obtained by irradiating the photoresist layer resulting from step (2A) with a patterned structure between a radiation source and the photoresist layer through a radiation-opaque mask.

[0061] When a positive photoresist is used, step (2B) can provide radiation-modified regions of the photoresist layer that are chemically modified, for example to effect depolymerization / decomposition, thus advantageously obtaining high solvent solubility and non-radiation-modified regions of said photoresist layer that are unaffected and thus advantageously maintain substantial solvent resistance.

[0062] When a negative photoresist is used, step (2B) can provide radiation-modified regions of the photoresist layer that are hardened, thus advantageously achieving high solvent resistance and non-radiation-modified regions of the photoresist layer that are not hardened and thus advantageously maintain substantial solvent solubility.

[0063] In substep (2C), generally, either the radiation-modified or the non-radiation-modified areas of the photoresist layer are advantageously removed. Removal of said areas can be achieved by standard means, nevertheless it is understood that treatment with an organic solvent is one of the preferred means for removing either the radiation-modified or the non-radiation-modified areas. The organic solvent used in this substep (2C) is selected by the skilled person according to the nature of the photoresist, preferably among those that are not capable of attacking the underlying layer (LO).

[0064] The result of sub-step (2C) is therefore a patterned layer (LO) comprising a pattern of areas covered with photoresist and areas not covered with photoresist, advantageously the areas covered with photoresist being areas of layer (LO) covered by areas of the photoresist layer that have not been removed in sub-step (2C).

[0065] In step (3), the uncovered areas of said patterned layer (LO) of polymer (F) are at least partially removed to obtain a patterned structure comprising a pattern of layer (LO) on said substrate according to the method of the invention.

[0066] The method for producing a patterned structure on a substrate of the present invention may comprise further steps, in which case the patterned structure obtained in step (3) is used as an intermediate structure for depositing and / or patterning and / or removing further layers.

[0067] In particular, the method may comprise a step (4) of applying a further coating layer of material (M) onto the patterned structure comprising a pattern of layer (LO) on said substrate, in order to obtain a patterned structure comprising a pattern of layer (LO) coated with material (M), and may comprise a further subsequent step (5) of removing said pattern of layer (LO) coated with material (M) in order to obtain a patterned structure comprising a corresponding negative pattern of the layer of material (M).

[0068] The material (M) can be an organic semiconducting material, an organometallic material, a biological material, a metallic material, etc.

[0069] Similarly, the choice of substrate is not particularly limited and depends on the intended use of the patterned structure. For example, substrates made of polyimide (PI), polyethylene terephthalate (PET), polyethylene naphthalate (PEN), polyetherimide (PEI), polyamideimide (PAI), glass, silicon, silicon oxide, indium tin oxide (ITO), indium zinc oxide, aluminum doped zinc oxide (AZO), indium doped cadmium oxide, transparent mixed oxides such as aluminum, gallium or indium doped zinc oxide (AZO, GZA or IZO), carbon nanotubes, graphene, formulations containing silver nanoparticles, polyaniline, inherently conductive polymers such as PEDOT:PSS.

[0070] The substrate is generally flat in shape and can have the form of a sheet or film, including a flexible film. The substrate may include electrodes or other types of electrical connections, including metal electrodes of Cu, Al, Mo, Ag, Mg, or alloys combining two or more of the foregoing metallic elements, among others.

[0071] To the extent that the disclosure of any of the patents, patent applications, and publications incorporated herein by reference conflicts with this description to the extent that it may render a term unclear, this description shall control.

[0072] The invention will now be described in more detail with reference to the following examples, the purpose of which is merely illustrative and not limiting the scope of the invention. EXAMPLES

[0073] raw materials As fluoropolymers, several different amorphous perfluorocopolymers are used that consist essentially of repeat units derived from 2,2,4-trifluoro-5-trifluoromethoxy-1,3-dioxole and repeat units derived from tetrafluoroethylene (TFE), more specifically: (FC-1): Fluoropolymer (FC-1) is an amorphous perfluoropolymer having an intrinsic viscosity of 38 cc / g and a concentration of carboxylic acid end groups of 9 mmol / kg; (FC-2): Fluoropolymer (FC-2) is an amorphous perfluoropolymer having an intrinsic viscosity of 14 cc / g and a concentration of carboxylic acid end groups of 20 mmol / kg; (FC-3): Fluoropolymer (FC-3) is an amorphous perfluoropolymer with an intrinsic viscosity of 33 cc / g and a concentration of carboxylic acid end groups below the detection limit of the technique used; (F-1): Fluoropolymer (F-1) is an amorphous perfluoropolymer with an intrinsic viscosity of 12 cc / g and a concentration of carboxylic acid end groups below the detection limit of the technique used. (FC-1), (FC-2) and (FC-3) are used in comparative examples, and (F-1) is the polymer (F) used in the examples of the present invention.

[0074] Determination of the intrinsic viscosity of the polymer (F) The intrinsic viscosity (η) [dl / g] was determined by measuring the drop time at 30° C. of a solution of the polymer (F) in FLUORINERT® FC72 (perfluorohexane) at a concentration of 1 g / dl using an Ubbelhode viscometer, using the Solomon-Ciuta equation (reproduced below):

number

[0075] Determination of carboxylic acid end groups of polymer (F) The amount of carboxylic acid end groups was determined according to the method described by PIANCA, M., et al. End groups in fluoropolymers. Journal of Fluorine Chemistry. 1999, vol. 95, p. 71-84. The concentration of the relevant chain ends is expressed as millimoles of groups per kg of polymer (F) and is expressed in their acidic form (-COOH), acyl halide form (-COF), and chloride form (-COOX). b , X b contains carboxylic acid end groups of (alkyl)ammonium or metal cations. The detection limit for the determination of carboxylic acid end groups is 0.1 mmol / Kg.

[0076] Determination of layer thickness on substrate The thickness of the layers deposited on the substrates was determined using a Filmetrics F50 Automated Film Thickness Mapping. The complex refractive index value of the polymer (F), used to calculate the thickness from the reflectance spectrum, was n 489nm = 1.331, k 489nm =0, n 589nm = 1.329, k 589nm =0, n 656nm = 1.328, k 656nm =0.

[0077] Preparation of stripper-solvent mixture [hereinafter, stripper (SM-1)] 10 g of cyclopentanol (purchased from Sigma-Alrich) was added to 1990 g of NOVEC® 7300 (purchased from 3M) in a 2 L plastic bottle. The plastic bottle was shaken for 1 hour, resulting in a blend of cyclopentanol and NOVEC® 7300 at a cyclopentanol concentration of 0.5 wt %.

[0078] Embodiments 1 to 3 A 20 nm layer of LG201 material (purchased from LG chemical, acting as ETL {electron transport layer}) was deposited on a 1 inch wafer using thermal evaporation method (LESKER Co., LTD., KJLL Spectros Deposition system.).

[0079] The polymer solution was coated onto the thus prepared ETL-containing wafer substrate by spin coating method under the conditions detailed below: Spin coater: SUSS Mircrotec Delta6RC, 1600 rpm for 50 seconds.

[0080] The coated ETL-containing wafer substrates were baked on a hotplate at 100° C. for 10 minutes to form a lift-off layer of polymer (F-1) or comparative polymers (FC-1) to (FC-3), approximately 1 μm thick. The lift-off layer was removed by immersion in a bath of stripping medium using a stripper solvent mixture as detailed in the examples below, followed by drying.

[0081] Determination of F residues in LG201 (ETL) layer after peeling off lift-off layer F residues were determined using TOF-SIM analysis using a TOFSIMS 5 instrument from ionTOF under the following conditions: 60 Kev, current: 0.38 pA, area 500 × 500 μm 2 The intensities of the peaks detected at m / z = 19 (F-ions), m / z = 31 (CF-ions) and m / z = 38 (F2-ions) were normalized to the intensities of the same peaks detected from the neat surface of LG201.

[0082] The results are summarized in the table below. Example 1C (comparative) provides measurements of F residues after a) formation of a layer (OL) of polymer (FC-1) and b) removal of the polymer by immersion in neat Novec® 7300; Example 2C (comparative) provides measurements of F residues after a) formation of a layer (OL) of polymer (FC-1) and b) removal of the polymer using a stripping agent (SM-1); Example 3C (comparative) provides measurements of F residues after a) formation of a layer (OL) of polymer (FC-2) and b) removal of the polymer using neat NOVEC® 7300; Example 4C (comparative) provides measurements of F residues after a) formation of a layer (OL) of polymer (FC-2) and b) removal of the polymer using a stripping agent (SM-1); Example 5 (according to the invention) provides a) the formation of a layer (OL) of polymer (F) and b) the measurement of F residues after removal of the polymer using a stripping agent (SM-1); - Example 6C (comparative) provides measurements of F residues after a) formation of a layer (OL) of polymer (FC-3) and b) removal of the polymer using a stripping agent (SM-1).

[0083] [Table 1]

[0084] The above table clearly demonstrates that the best performance in terms of effective removal of layer (OF) is obtained when a selection of polymer (F) is combined with a stripper solvent mixture according to the method of the present invention.

[0085] OLED Device Fabrication and Performance An OLED device was fabricated having the above structure: ITO substrate / HATCN(5nm) / HT011(50nm) / HATCN(5nm) / HT211(140nm) / NS60:H111:GD270(40nm)[43.5:43.5:13] / LG201(30nm)→layer(LO)→removal by stripper / Liq(1nm) / Al(100nm).

[0086] The following ingredients were used: HIL layer: HATCN (1,4,5,8,9,11-hexaazatriphenylene hexacarbonitrile), HT011 (N4,N4'-di(naphthalen-1-yl)-N4,N4'-diphenylbiphenyl-4,4'-diamine) HTL layer: HT211 (N-[1,1'-diphenyl]-4-yl-9,9-dimethyl-N-[4-(9-phenyl-9H-carbazol-3-yl)phenyl]-9H-fluoren-2-amine) EML layer: NS60 (trade name of Nippon Steel Chemical Co., Ltd.), H111 (4-[3-(2-triphenylenyl)phenyl]-dibenzothiophene), GD270 (trade name of P&H Tech.) ETL layer: LG201 (trade name of LG Chemical Co., Ltd.) EIL layer: Liq (8-quinolinolate lithium) Cathode electrode: Al (Kojundo co., Ltd. from Japan)

[0087] The devices were prepared according to the following detailed procedures. First stack (HIL~ETL) 1) The ITO substrate was cleaned in an ultrasonic process using deionized water for 10 minutes and then isopropanol for 10 minutes. 2) The surface of the ITO substrate was treated with oxygen plasma (conditions: (120 W, Ar 4 L / min, O2 12 mL / min, Levi system co., LTD, Korea) 3) The plasma-treated ITO substrate was introduced into a vacuum chamber for deposition of OLED materials. 4) OLED materials are placed under high vacuum (10 -7 The deposition was performed on the substrate at vacuum conditions of less than 1000 torr. I. Cambium layer (LO) on ETL 1) The ITO substrate with the ETL layer was retrieved from the vacuum chamber, transferred to a glove box, and packaged to prevent the ITO substrate from being exposed to air. 2) Polymers (F-1) and / or (FC-1) to (FC-3) were coated on the surface of the ETL under fixed spin coating conditions (spin coater: SUSS Mircrotec Delta6RC, 1600 rpm, 50 seconds). 3) The sample substrate was dried on a hot plate at 100° C. for 10 minutes. II. Release layer (LO) 1) To remove the layer (LO) from the surface of the ETL, the sample substrate was immersed in a stripper bath for 10 minutes. 2) The sample substrate was dried on a hot plate at 100° C. for 10 minutes. III. Second Deposition (EIL~Al) 1) The sample substrate was packed to prevent exposure to air and taken out of the glove box. 2) The sample substrate was introduced into a vacuum chamber. 3) OLED materials were deposited on the sample substrate under high vacuum (vacuum condition less than 10 Torr). 4) To obtain the devices, after Al deposition, the sample substrates were sealed in a glove box. IV. Evaluating Device Performance 1) The characteristics of the IVL device were measured by a radio spectrometer. EQE (in %) and 10mA / cm 2 The voltage (V) at was determined (CS2000 Konica-Minolta, Japan). 2) The lifetime of the device was measured using an OLED lifetime system (BO TEST Co.LTD-Poland) under constant current density.

[0088] The results are summarized in Table 2 below.

[0089] [Table 2]

[0090] The data summarized above well demonstrates that the performance of device (1) is substantially identical to that observed in a reference OLED device of the same construction, but without the formation and subsequent removal of a lift-off layer.

[0091] The emission lifetimes of the reference OLED device, device (1), and comparative device (2C) are shown in FIG. 1, and in particular, device (1) fabricated using the method of the present invention has an emission time profile that is substantially indistinguishable from that of the reference OLED device, while comparative device (2C) shows significant decay in emission.

Claims

1. - a repeating unit having an alicyclic structure in the main chain of the fluoropolymer and derived from at least one fluoromonomer A; Optionally, - repeat units derived from at least one fluoromonomer B different from fluoromonomer A; A composition comprising at least one of said fluoropolymers comprising (The fluoropolymer is - have an intrinsic viscosity of less than 30 cc / g, measured at 30°C in perfluorohexane as a solvent; - containing an amount of carboxylic acid end groups of less than 8 mmol / kg (hereinafter polymer (F)) 1. A method for at least partially removing a lift-off layer made from The method comprises: - providing an assembly comprising a support material having an area covered with a layer; to obtain at least partial removal of said layer, a) 15.0 MPa １／２ Hansen solubility parameter δ less than Ｔ At least one fluorinated solvent [solvent (F)] having the formula b) 10 to 10,000 ppm, based on the weight of solvent (F), of at least one polar organic solvent [solvent (P)] different from solvent (F), said solvent (P) having a viscosity of at least 20.0 MPa １／２ and at most 26.0 MPa １／２ Hansen solubility parameter δ Ｔ and contacting the assembly with a stripping solvent mixture comprising:

2. 2. The method of claim 1, wherein fluoromonomer A is selected from the group consisting of fluoromonomers that have alicyclic structures in their monomeric form and fluoromonomers that do not have alicyclic structures in their monomeric form but provide alicyclic structures in the resulting repeat units of polymer (F) upon cyclopolymerization, and fluoromonomer A is a perfluoromonomer.

3. The repeating units derived from the fluoromonomer A are represented by the following formulas (1) to (3): 【Chemistry 1】 (In the formula: In the formula (1), p, q, and r are each independently 0 or 1; ｆ１ and R ｆ２ may be the same or different, and each of １ ~C ５ Perfluoroalkyl group or C １ ~C ５ is a perfluoroalkoxy group, R ｆ３ is C １ ~C ３ It is a perfluoroalkylene group, and as a substituent, １ ~C ５ Perfluoroalkyl group or C １ ~C ５ may have perfluoroalkoxy groups, In the formula (2), s is 0 or 1; R ｆ４ , R ｆ５ , R ｆ６ and R ｆ７ may be the same or different and each is a fluorine atom or C １ -C ５ is a perfluoroalkyl group, R ｆ８ is a fluorine atom, C １ ~C ５ Perfluoroalkyl group or C １ ~C ５ A perfluoroalkoxy group, provided that when s=0, R ｆ４ and R ｆ５ can be joined to form a spiro ring, In the formula (3), R ｆ９ , R ｆ１０ , R ｆ１１ and R ｆ１２ may be the same or different and each is a fluorine atom or C １ ~C ５ Perfluoroalkyl group or C １ ~C ５ perfluoroalkoxy group) The method of claim 2 , wherein the method is represented by any one of the following:

4. The repeating unit derived from the fluoromonomer A is represented by the following formulas (4) to (19): 【Chemistry 2】 The method of claim 3, wherein the compound is selected from the group consisting of those represented by:

5. The repeating unit derived from the fluoromonomer A is represented by the following formulas (20) to (30): 【Chemistry 3】 The method of claim 3, wherein the compound is selected from the group consisting of those represented by:

6. The repeating units derived from the fluoromonomer A are represented by the following formulas (31) to (33) in accordance with formula (2): 【Chemistry 4】 The method of claim 3, wherein the compound is selected from the group consisting of those represented by:

7. The polymer (F) contains repeating units derived from at least one fluoromonomer B different from the fluoromonomer A, and the fluoromonomer B is (a) C such as tetrafluoroethylene (TFE) and hexafluoropropylene (HFP) ２ ~C ８ Perfluoroolefins, (b) vinylidene fluoride (VDF), vinyl fluoride, trifluoroethylene (TrFE), hexafluoroisobutylene (HFIB), ２ =CH-R ｆ１ (In the formula, R ｆ１ is C １ ~C ６ Hydrogen-containing C alkyl groups such as perfluoroalkylethylenes ２ ~C ８ Fluoroolefins, (c) C such as chlorotrifluoroethylene (CTFE) ２ ~C ８ Chloro- and / or bromo-containing fluoroolefins; (d) Formula CF ２ =CFOR ｆ１ (In the formula, R ｆ１ CF ３ (PMVE), C ２ F ５ Or C ３ F ７ C etc. １ ~C ６ perfluoroalkyl vinyl ethers (PAVEs), (e) In particular, the formula CF ２ = CFOCF ２ OR ｆ２ (R ｆ２ is -CF ２ CF ３ , -CF ２ CF ２ -O-CF ３ , and -CF ３ C etc. １ ~C ３ perfluoromethoxyalkyl vinyl ethers of the formula CF ２ =CFOX ０ (In the formula, X ０ is a C group containing one or more ethereal oxygen atoms １ ~C １２ perfluorooxyalkyl vinyl ethers, (f) Formula CF ２ = CFOY ０ (In the formula, Y ０ is C １ ~C １２ A perfluoro(oxy)alkylene group, optionally containing one or more ethereal oxygen atoms, is represented by -SO ２ X, -COX, PO ２ X is a halogen or -OX ａ is a group, and X ａ is H, an ammonium group or a metal cation; The method according to any one of claims 1 to 6, wherein the compound is selected from the group consisting of:

8. The polymer (F) is - 20 to 95 mol % of repeating units having an alicyclic structure in the main chain of said fluoropolymer and derived from at least one fluoromonomer A, based on the total moles of repeating units of polymer (F); - 5 to 80 mol % of repeat units derived from at least one fluoromonomer B different from fluoromonomer A, based on the total moles of repeat units of polymer (F).

9. The polymer (F) is - repeat units derived from at least one fluoromonomer A selected from the group consisting of perfluoro(2-methylene-4-methyl-1,3-dioxolane), perfluoro(2,2-dimethyl-1,3-dioxole), perfluoro(1,3-dioxole), 2,2,4-trifluoro-5-trifluoromethoxy-1,3-dioxole and perfluoro(3-butenyl vinyl ether); and - a repeat unit derived from tetrafluoroethylene (TFE).

10. The polymer (F) is contains an amount of carboxylic acid end groups of at most 7.5 mmol / kg, and / or The method according to any one of claims 1 to 9, having an intrinsic viscosity of less than 25 cc / g and / or at least 5 cc / g.

11. The solvent (F) has the following solubility parameters: Dispersed components, δ Ｄ , 11.0~14.50 Polar components, δ Ｐ , 0.1~5.0 Hydrogen-bonding component, δ Ｈ 11. The method of claim 1, wherein the .lambda.-value is selected from the group consisting of those having a .lambda.-value of 0.0 to 2.

0.

12. The solvent (F) is sp ３ 12. The method of claim 11, wherein the fluorocarbon is selected from the group consisting of hydrofluoroethers (HFEs), which are ethers that contain a partially fluorinated hydrocarbon structure that contains both hydrogen and fluorine atoms bonded to hybridized carbons.

13. The solvent (P) has a solubility parameter δ Ｔ is at least 20.0 MPa １／２ and at most 25.5 MPa １／２ and / or 13. The process according to any one of claims 1 to 12, wherein the amount of solvent (P) is from 100 to 1500 ppm, based on the weight of solvent (F).

14. 1. A method for producing a patterned structure on a substrate, comprising: （１） - a repeating unit having an alicyclic structure in the main chain of the fluoropolymer and derived from at least one fluoromonomer A; Optionally, - repeat units derived from at least one fluoromonomer B different from fluoromonomer A; A composition comprising at least one of said fluoropolymers comprising (The fluoropolymer is - have an intrinsic viscosity of less than 30 cc / g, measured at 30°C in perfluorohexane as a solvent; - applying to at least a portion of said substrate a polymer (hereinafter polymer (F)) comprising an amount of carboxylic acid end groups of less than 8 mmol / kg, to obtain a layer composition comprising polymer (F) on said substrate; (2) patterning said layer to obtain a patterned layer comprising a pattern of covered and uncovered areas; (3) at least partially removing the uncovered areas of the patterned layer by contacting with a stripping solvent mixture according to any one of claims 1 to 13 to obtain a patterned structure comprising a pattern of a layer on the substrate.

15. 15. The method of claim 14, Step (2) a substep (2A) of forming a layer of photoresist on said layer to obtain a photoresist layer; a substep (2B) of exposing said photoresist layer to patterned radiation to obtain a patterned photoresist layer comprising radiation-modified and non-radiation-modified regions; and / or a substep (2C) of substantially removing either said radiation-modified regions or said non-radiation-modified regions to obtain a patterned layer comprising a pattern of photoresist-covered and non-photoresist-covered regions; The method may comprise a further step (4) of applying a further coating layer of material (M) onto the patterned structure comprising the pattern of the layer on the substrate, in order to obtain a patterned structure comprising a pattern of the layer coated with material (M), and a further subsequent step (5) of removing the pattern of the layer coated with material (M) in order to obtain a patterned structure comprising a corresponding negative pattern of the layer of material (M), The material (M) may be an organic semiconducting material, an organometallic material, a biological material, and a metallic material; and / or 15. The method of claim 14, wherein the substrate may be made of polyimide (PI), polyethylene terephthalate (PET), polyethylene naphthalate (PEN), polyetherimide (PEI), polyamideimide (PAI), glass, silicon, silicon oxide, indium tin oxide (ITO), indium zinc oxide, aluminum doped zinc oxide (AZO), indium doped cadmium oxide, transparent mixed oxides such as aluminum, gallium or indium doped zinc oxide (AZO, GZA or IZO), carbon nanotubes, graphene, formulations containing silver nanoparticles, intrinsically conductive polymers such as polyaniline.

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