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Effects of Humidity on Unencapsulated Poly(thiophene) Thin Film Transistors



Michael L. Chabinyc, Fred Endicott, B D. Vogt, Dean DeLongchamp, Eric K. Lin, Yiliang Wu, Ping Liu, Beng S. Ong


The effects of humidity on unencapsulated polymeric thin-film transistors (TFTs) were investigated. TFTs were fabricated on glass substrates with inorganic gate dielectric and a semiconducting layer of poly[5,5 -bis(3-dodecyl-2-thienyl)-2,2 -bithiophene], PQT-12. The field effect mobility of PQT-12 TFTs decreases and the rate of trapping of charge carriers increases under increasing humidity. The amount of water absorbed by the PQT-12 films was measured using a quartz crystal microbalance. Thin films of PQT-12 absorb comparable amounts of water to the carrier concentration in TFTs under routine operating conditions (humidity of 30% R.H. and gate voltage of -30 V); the changes in electrical characteristics under humid atmospheres are attributed to the interaction of absorbed water with the carriers in the film.
Applied Physics Letters
88 No 11


field effect, humidity, poly(3-hexyl thiophene), polymer, semiconductor, transistor


Chabinyc, M. , Endicott, F. , Vogt, B. , DeLongchamp, D. , Lin, E. , Wu, Y. , Liu, P. and Ong, B. (2006), Effects of Humidity on Unencapsulated Poly(thiophene) Thin Film Transistors, Applied Physics Letters, [online], (Accessed June 20, 2024)


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Created March 12, 2006, Updated October 12, 2021