Effect of the interlayer for source-drain electrodes on a solution-processed zinc-tin-oxide TFT

An interlayer was introduced between the source and drain (S-D) electrodes and the semiconductor in a solution-processed zinc tin oxide (ZTO) thin-film transistor (TFT). The ZTO TFT with a MoO3 interlayer of 0.5 nm between the ZTO and the S-D electrodes displayed better properties: a mobility of 5.6 cm2/V s, a threshold voltage (Vth) of −1.3 V and a subthreshold slope of 0.9 V/dec with better bias stability and hysteresis. This improvement is attributed to the MoO3’s reduction to a conductor, MoO2, and to the inter-diffusion of the interlayer between the active channel and the S-D layers, as confirmed by the XPS spectra and by a TEM-EDX analysis, respectively.