Sputter protective layer for organic electronic devices

A thin film transistor, comprising a substrate, one or more source/drain electrodes, at least one gate electrode, an organic semiconductor layer, and an organic gate insulator (OGI) layer;

• wherein the organic gate insulator (OGI) layer has a dielectric constant (k)<3.0 @ 1000 Hz, said organic gate insulator layer being over-coated with a cross-linked organic layer (OSPL);
• wherein the cross-linked layer is a free-radical photocured layer;
• wherein the cross-linked organic layer thereon has a permittivity (k)>3.3 @ 1000 Hz;
• preferably wherein the cross-linked organic layer thereon has a permittivity (k)>3.5 at 1000 Hz;
• more preferably wherein the cross-linked organic layer thereon has a permittivity (k)>4.0 at 1000 Hz;
• wherein the cross-linked organic layer thereon is obtainable by polymerising a solution comprising at least one multi-functional acrylate, a fluorosurfactant and an acrylate and/or methacrylate-functionalised silicone surfactant, and one or more initiators;
• wherein the organic semiconductor layer comprises one or more material selected from the group consisting of tetracene, chrysene, pentacene, diketopyrrolopyrroles, substituted benzothienobenzothiophenes (C8-BTBT), dinaphthothienothiophenes (DNTT), pyrene, perylene, coronene, or substituted derivatives of these;
• oligomeric para substituted phenylenes such as p-quaterphenyl (p-4P), p-quinquephenyl (p-5P), p-sexiphenyl (p-6P), or soluble substituted derivatives of these, poly(3-substituted thiophene), poly(3,4-bisubstituted thiophene), polybenzothiophene, polyisothianapthene, poly([Lambda]/-substituted pyrrole), poly(3-substituted pyrrole), poly(3,4-bisubstituted pyrrole), polyfuran, polypyridine, poly-1,3,4-oxadiazoles, polyisothianaphthene, poly([Lambda]/-substituted aniline), poly(2-substituted aniline), poly(3-substituted aniline), poly(2,3-bisubstituted aniline), polyazulene, polypyrene;
• pyrazoline compounds;
• polyselenophene;
• polybenzofuran;
• polyindole;
• polypyridazine;
• benzidine compounds;
• stilbene compounds;
• triazines;
• substituted metallo- or metal-free porphines, phthalocyanines, fluorophthalocyanines, naphthalocyanines, naphthalene diimides or fluoronaphthalocyanines;
• C60 and C70 fullerenes;
• A/.[Lambda]/′-dialkyl, substituted dialkyl, diaryl or substituted diaryl-1,4,5,8-naphthalenetetracarboxylic diimide and fluoro derivatives;
• [Lambda]/.[Lambda]/′-dialkyl, substituted dialkyl, diaryl or substituted diaryl 3,4,9,10-perylenetetracarboxylicdiimide;
• bathophenanthroline;
• diphenoquinones;
• 1,3,4-oxadiazoles;
• 11,11,12,12-tetracyanonaptho-2,6-quinodimethane;
• [alpha], [alpha]′-bis(dithieno[3,2-b2′,3′-d]thiophene);
• dithieno[2,3-d;2′,3′-d′]benzo[1,2-b;4,5-b′]dithiophene (DTBDT);
• poly dithienobenzodithiophene-co-diketopyrrolopyrrolebithiophene (PDPDBD);
• isoindigo-Bithiophene-(IIDDT-C3), thieno[3,2-b]thiophene-5-fluorobenzo[c][1,2,5]thiadiazole copolymers, di(thiophen-2-yl)thieno[3,2-b]thiophene (DTTT);
• 2,8-dialkyl, substituted dialkyl, diaryl or substituted diaryl anthradithiophene;
• 2,2′-bibenzo[1,2-b:4,5-b′jdithiophene, benzothienobenzothiophene (BTBT) polymers benzodithiazole polymers, and mixtures thereof.