Influence of the gate leakage current on the stability of organic single-crystal field-effect transistors

We investigate the effect of a small leakage current through the gate insulator on the stability oforganic single-crystal field-effect transistors (FETs). We find that, irrespective of the specific organic molecule and dielectric used, leakage current flowing through the gate insulator results in an irreversible degradation of the single-crystal FET performance. This degradation occurs even when the leakage current is several orders of magnitude smaller than the source-drain current. The experimental data indicate that a stable. operation requires the leakage current to be smaller than 10-9 A/cm(2). Our results also suggest that gate leakage currents may determine the lifetime of thin-film transistors used in applications. (C) 2005 American Institute of Physics.