Investigation on Channel Plasma Effect in Doped Tin-Oxide Thin-Film Transistors Using Experiments and Simulation

Abstract

In this paper, we reported ap-channel tin-oxide (SnO) thin-film transistor (TFT) by introducing aluminum (AI) dopant in the SnO channel layer. An extremely high field-effect mobility $(\mu_{\text{FE}}$) of 8 cm2/V·s and an on-to-off current ratio $(I_{\text{on}}/I_{\text{off}})$ of ~103 were obtained in this p-channel Al-doped SnO (A1:SnO) TFT. Furthermore, the device performances of the Al:SnO TFT including the $I_{\text{on}}/I_{\text{off}}$ and subthreshold swing (SS) were greatly improved by fluorine plasma treatment (FPT) on the Al:SnO channel layer. In addition, in order to study the channel plasma effect on the device performances, TCAD simulation was carried out based on the p-channel Al:SnO TFT by introducing the density of state (DOS) model. The simulation results indicated that the device performance enhancements were further achieved because the attributes of acceptor-like Gaussian defect states and donor-like band-tail state were modified during the FPT.