Influence of Substrate Surface Chemistry on the Performance of Top-Gate Organic Thin-Film Transistors

International audienceOrganic thin-film transistor (OTFT) performance depends on the chemical characteristics of the interface between functional semiconductor/dielectric/ conductor materials. Here we report for the first time that OTFT response in top-gate architectures strongly depends on the substrate chemical functionalization. Depending on the nature of the substrate surface, dramatic variations and opposite trends of the TFT threshold voltage (∼(50 V) and OFF current (105 !) are observed for both p- and n-channel semiconductors. However, the field-effect mobi- lity varies only marginally (∼2 ). Our results demonstrate that the substrate is not a mere passive mechanical support