Temperature-dependent hole transport for pentacene thin-film transistors with a SiO2 gate dielectric modified by (NH4)2Sx treatment

The effect of a SiO2 gate dielectric modified by (NH4)2Sx treatment on the temperature-dependent hole transport behavior for pentacene-based organic thin-film transistors (OTFTs) is studied. (NH4)2Sx treatment leads to the formation of SSi bonds (i.e., the formation of a sulfurated layer) on the SiO2 surface that serves to reduce the SiO2 capacitance, increasing the value of the hole mobility in OTFTs. The temperature-dependent hole transport is dominated by the multiple trapping model. It is shown that (NH4)2Sx treatment leads to a reduction in the activation energy, resulting from the formation of a sulfurated layer at the pentacene/SiO2 interface that serves to suppress the pentacene-SiO2 interaction. (NH4)2Sx treatment provides an opportunity to realize the stable and reliable carrier conduction behavior for OTFTs.