Patent ID: 7671359

Claim:
A thin film transistor comprising: a gate electrode; source and drain electrodes insulated from the gate electrode; a semiconductor layer insulated from the gate electrode and electrically connected to the source and drain electrodes; an insulating layer for insulating the gate electrode from the source and drain electrodes or the semiconductor layer; and a carrier blocking layer interposed between the semiconductor layer and the insulating layer; wherein the carrier blocking layer is a hole blocking layer; wherein the hole blocking layer comprises a material having a HOMO level greater than that of the organic semiconductor forming the semiconductor layer; and wherein the hole blocking layer is selected from the group consisting of Alq3 (tris(8-hydroxyquinoline)aluminum), F4-TCNQ (2,3,5,6-Tetrafluoro-7,7,8,8-tetracyano-p-quinodimethane), NTCDA (1,4,5,8-naphthalene-tetracarboxylic acid dianhydride), PTCDA (3,4,9,10-perylenetetracarboxylic dianhydride), BCP (bathocuproine), CBP (4,4′-N,N′-dicarbazolyl-biphenyl), copper phthalocyanine (CuPc), and PTCBI (3,4,9,10-perylenetetracarboxylic bisbenzimidazole).