title: Controlling the Al-doping profile and accompanying electrical properties of rutile-phased TiO2 thin films.
abstract: The role of Al dopant in rutile-phased TiO2 films in the evaluation of the mechanism of leakage current reduction in Al-doped TiO2 (ATO) was studied in detail. The leakage current of the ATO film was strongly affected by the Al concentration at the interface between the ATO film and the RuO2 electrode. The conduction band offset of the interface increased with the increase in the Al dopant concentration in the rutile TiO2, which reduced the leakage current in the voltage region pertinent to the next-generation dynamic random access memory application. However, the Al doping in the anatase TiO2 did not notably increase the conduction band offset even with a higher Al concentration. The detailed analyses of the leakage conduction mechanism based on the quantum mechanical transfer-matrix method showed that Schottky emission and Fowler-Nordheim tunneling was the dominant leakage conduction mechanism in the lower and higher voltage regions, respectively. The chemical analyses using X-ray photoelectron spectroscopy corroborated the electrical test results.
authors.affiliation: Department of Materials Science and Engineering and Inter-university Semiconductor Research Center, Seoul National University , Seoul 151-742, Republic of Korea.
authors.forename: Woojin
authors.initials: W
authors.lastname: Jeon
authors.forename: Sang Ho
authors.initials: SH
authors.lastname: Rha
authors.forename: Woongkyu
authors.initials: W
authors.lastname: Lee
authors.forename: Yeon Woo
authors.initials: YW
authors.lastname: Yoo
authors.forename: Cheol Hyun
authors.initials: CH
authors.lastname: An
authors.forename: Kwang Hwan
authors.initials: KH
authors.lastname: Jung
authors.forename: Seong Keun
authors.initials: SK
authors.lastname: Kim
authors.forename: Cheol Seong
authors.initials: CS
authors.lastname: Hwang