Pentacene-based thin film transistors with titanium oxide-polystyrene/polyst yrene insulator blends: High mobility on high K dielectric films.
05 February 2007
High K titanium oxide-polystyrene nanocomposite (TiO2-PS) has been blended with polystyrene (PS) to generate gate dielectric films with permittivities ranging from 2.5 to 8 in order to investigate permittivity effects on pentacene TFT performance. An order of magnitude increase in saturation mobility is observed for TiO2-PS (K = 8) as compared to PS devices (K =2.5). Morphological differences for pentacene grown on TiO2-PS/PS dielectrics are thought to be responsible for the observed mobility enhancements. The high performance of pentacene on TiO2-PS devices suggests that high permittivity films are not incompatible with high mobility devices.