High-Mobility Transparent SnO_2 and ZnO-SnO_2 Thin-Film Transistors with SiO_2/Al_2O_3 Gate Insulators

摘要

Using a double-layered gate insulator [SiO_2 (100 nm)/Al_2O_3 (10 nm)] and a dry-etching process for the channel layer, we could obtain high mobility top-gate SnO_2 and ZnO-SnO_2 (ZTO) transparent thin-film transistor (TTFT). After annealing at 300℃, for 1 h in O_2 ambient, the saturated mobility of SnO_2 TTFT was 17.4 cm~2 s~(-1) V~(-0), and that of ZTO TTFT was 50.4 cm~2 s~(-1) V~(-1). Generally, both devices operated in the enhancement mode with a drain current on-off ratio of ～10~6.