Bias temperature instability in hydrogenated thin-film transistors

The bias temperature instability is studied in hydrogenated n- and p-channel thin-film MOS transistors (TFT's) fabricated using a low-temperature process compatible with active matrix liquid crystal display application. We observe significant threshold voltage and subthreshold slope degradation under both positive and negative bias stress. The degradation increases with increased hydrogen incorporation and is temperature and electric field activated. The experimental results are explained based on trap creation model which depends on the hydrogen content of the device.