ZnO thin-film transistors with polycrystalline (Ba,Sr)TiO_3 gate insulators

摘要

The electrical characteristics of ZnO thin-film transistors with high-k (Ba,Sr)TiO_3 gate dielectrics are presented. The ZnO and (Ba,Sr)TiO_3 thin films were deposited on Pt, exhibiting polycrystalline characteristics. The thin-film devices demonstrated transistor behavior over the range of 0-10 V with a stable threshold voltage of approximately 1.2 V. The field effect mobility, subthreshold slope, and on/off ratio were measured to be 2.3 cm~2 V~(-1) s~(-1), 0.25 V/decade, and 1.5 x 10~8, respectively. The measured transistor performance characteristics suggest that ZnO/(Ba,Sr)TiO_3 structures are well suited for both polycrystalline thin-film transistors for display applications and future higher performance transistors based on single crystal ZnO.