The influence of molecular weight on the microstructure and thin film transistor characteristics of pBTTT polymers.

TitleThe influence of molecular weight on the microstructure and thin film transistor characteristics of pBTTT polymers.
Publication TypeConference Paper
Year of Publication2006
AuthorsR. Hamilton, C. Bailey, Warren Duffy, M.J. Heeney, M. Shkunov, D. Sparrowe, S. Tierney, I. McCulloch, R.J. Kline, D.M. DeLongchamp, and M.L. Chabinyc
EditorBao, Z, and D.J. Gundlach
Conference NameORGANIC FIELD-EFFECT TRANSISTORS V
PublisherSPIE
Conference Location1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA
ISBN Number0-8194-6415-5
AbstractA common strategy to improve the electrical performance of organic field effect transistors is to optimize the charge carrier mobility of the semiconducting thin film. Polymer semiconductor transport properties have shown a dependence on the chain length, due principally to the strong influence of molecular weight on the thin film microstructure. In this work, we report on a study of the influence of increasing molecular weight of poly(2,5-bis(3-docecylthiophen-2-yl)thieno[3,2-b]thiophenes) (pBTTT-C12) on the polymer bulk thermal properties, thin film microstructure and the electrical performance of thin film field effect transistor devices. Clear differences can be observed within a number average molecular weight range of 8,000 - 18,000 Dalton. A Liquid crystalline phase was only observed at the highest molecular weight, different thin film morphology was observed within the molecular weight range, and the field effect mobility was shown to increase with increasing molecular weight.
DOI10.1117/12.682874