Patent ID: 7485894

Claim:
A thin film transistor comprising: a gate electrode; source and drain electrodes insulated from the gate electrode; an organic semiconductor layer that is insulated from the gate electrode and is electrically connected to the source and drain electrodes; an insulating layer that insulates the gate electrode from the source and drain electrodes or the organic semiconductor layer; and an ohmic contact layer that is interposed between the source/drain electrodes and the organic semiconductor layer and that contains a hole transporting compound and/or is a self assembled monolayer (SAM) including a repeating unit of formula (1) below, or a moiety of formula (2) below: where X 1 and X 2 are each a single bonded, a substituted or unsubstituted C 1 -C 20 alkylene group, or -Z 1 -NH—C(═O)—O-Z 2 -, Z 1 and Z 2 are each a substituted or unsubstituted C 1 -C 20 alkylene group; Y 1 is a hole transporting unit; Y 2 , W 1 and W 2 are each hydrogen, a halogen atom, a C 1 -C 20 alkyl group, a C 1 -C 20 alkoxy group, or the hole transporting unit, at least one of Y 2 , W 1 and W 2 is the hole transporting unit; and * and *′ indicate binding with the source and drain electrodes or the organic semiconductor layer, wherein the hole transporting compound is at least one selected from the group consisting of where R 1 , R 2 , R 3 , R 4 , R 5 , R 6 and R 7 are each hydrogen, a substituted or unsubstituted C 6 -C 30 aryl group, or a substituted or unsubstituted C 5 -C 30 heteroaryl group, wherein at least one of R 1 , R 2 and R 3 , and at least one of R 4 , R 5 , R 6 and R 7 are a substituted or unsubstituted C 6 -C 30 aryl group, or a substituted or unsubstituted C 5 -C 30 heteroaryl group; R 8 is hydrogen, or a substituted or unsubstituted C 1 -C 30 alkyl group; Ar 1 is a substituted or unsubstituted C 6 -C 30 arylene group, or a substituted or unsubstituted C 5 -C 30 heteroarylene group; n is an integer from 1 to 10; and Q 1 , Q 2 , Q 3 , Q 4 and Q 5 are each selected from N, C, P and S.