Polymeric Substrate Spin-Cast diF-TESADT OTFT Circuits

We report 7- and 15-stage spin-cast contact- crystallized 2, 8-difluoro-5, ll-bis(triethylsilylethynyl) anthra- dithiophene (diF-TESADT) organic thin-film transistor (OTFT) ring oscillators on plastic substrates with a maximum frequency of more than 22 kHz and a propagation delay of less than 3.3 mus/stage at a supply bias of -80 V. The circuits have stable operation for a supply bias as small as -3 V (25-30 mus/stage). Spin-cast diF-TESADT OTFTs from a toluene solution on plastic substrates have a mobility of 0.1-0.2 cm²/V ldr s with a contact-related micro- structure from pentafluorobenzenethiol-treated Au source and drain electrodes.