A vertical polymer nanorod transistor was realized based on an air-stable poly[5,5'-bis(3-dodecyl-2-thienyl)-2,2'-bithiophene] with a high highest occupied molecular orbital energy level. The influence of the work function of the emitter on the performances of the space-charge-limited transistor was investigated. When MoO3/Al was used as the top emitter and indium tin oxide was used as the bottom collector, the operating voltage of 0.6 V, the on/off current ratio of 4 x 10(4), and the switching swing of 105 mV/decade were achieved. A low-power-consumption inverter was also demonstrated. (C) 2011 American Institute of Physics. [doi:10.1063/1.3668086]