Light, bias, and temperature effects on organic TFTs

In this work we present the instabilities observed in organic Thin-Film Transistors when subjected to stress test in different bias, temperature and illumination conditions. C-V measurements, indicate the presence of two distinct trapping phenomena. Appreciable charge trapping can be achieved using relatively high biases for long times (1000s). Illumination strongly enhances charge trapping only under positive gate biases, while it has no effect on the charge trapping/detrapping under negative gate bias. Charge detrapping is thermally activated coherently with trapping/detrapping at the SiO₂/pentacene interface from hydrogenoid species. A first order model explaining the observed relaxation kinetics is also presented.