Patent ID: 7923718

Claim:
A thin-film transistor, comprising: a source electrode; a drain electrode; a gate dielectric layer; and a polythiophene semiconductor layer; wherein the source electrode and drain electrode each comprise a first layer and a second layer, the first layer directly contacting the dielectric layer and separating the second layer from the dielectric layer, the second layer directly contacting the semiconductor layer; wherein the source electrode first layer has a work function differing from the energy level of the semiconductor layer by at least 1.0 eV; wherein the source electrode second layer has a work function differing from the energy level of the semiconductor layer by at most 0.2 eV; wherein the semiconductor layer has a channel length of from about 1 to about 5 micrometers; and wherein the transistor has a mobility of at least 0.39 cm 2 /v·sec and a current on/off ratio of at least about 10 7 .