High mobility n-type thin-film transistors based on N,N′-ditridecyl perylene diimide with thermal treatments

The authors demonstrated that N,N′-ditridecyl-3,4,9,10-perylenetetracarboxylic diimide (PTCDI-C13) thin-film transistors (TFTs) exhibited high field-effect electron mobility of 2.1cm2∕Vs by just annealing at an adequate temperature (140°C) after the TFT fabrications. While PTCDI-C13 formed c-axis oriented thin films, the thermal treatments improved crystallinity of the thin films as revealed by x-ray diffraction. The thermal treatment also affected thin-film morphologies; the morphologies changed from oval ball-like grains to flat and large tilelike grains, which had molecular height steps and whose size reached several micrometers.