Single crystal field-effect transistors based on an organic   selenium-containing semiconductor
  We report on the fabrication and characterization of single crystal field-effect transistors (FETs) based on diphenylbenzo diselenophene (DPh-BDSe). These organic field-effect transistors (OFETs) function as p-channel accumulation-mode devices. At room temperature, for the best devices, the threshold voltage is less than -7V and charge carrier mobility is nearly gate bias independent, ranging from 1cm2/Vs to 1.5 cm2/Vs depending on the source-drain bias. Mobility is increased slightly by cooling below room temperature and decreases below 280 K. 
R. Zeis, Ch. Kloc, K. Takimiya, Y. Kunugi, Y. Konda, N. Niihara and T.   Otsubo