title: Structural and electrical characteristics of high-κ Er2O3 and Er2TiO5 gate dielectrics for a-IGZO thin-film transistors.
abstract: In this letter, we investigated the structural and electrical characteristics of high-κ Er2O3 and Er2TiO5 gate dielectrics on the amorphous indium-gallium-zinc-oxide (a-IGZO) thin-film transistor (TFT) devices. Compared with the Er2O3 dielectric, the a-IGZO TFT device incorporating an Er2TiO5 gate dielectric exhibited a low threshold voltage of 0.39 V, a high field-effect mobility of 8.8 cm2/Vs, a small subthreshold swing of 143 mV/decade, and a high Ion/Ioff current ratio of 4.23 × 107, presumably because of the reduction in the oxygen vacancies and the formation of the smooth surface roughness as a result of the incorporation of Ti into the Er2TiO5 film. Furthermore, the reliability of voltage stress can be improved using an Er2TiO5 gate dielectric.
authors.affiliation: Department of Electronics Engineering, Chang Gung University, 333, Taoyuan, Taiwan. tmpan@mail.cgu.edu.tw.
authors.forename: Fa-Hsyang
authors.initials: FH
authors.lastname: Chen
authors.forename: Jim-Long
authors.initials: JL
authors.lastname: Her
authors.forename: Yu-Hsuan
authors.initials: YH
authors.lastname: Shao
authors.forename: Yasuhiro H
authors.initials: YH
authors.lastname: Matsuda
authors.forename: Tung-Ming
authors.initials: TM
authors.lastname: Pan