title: Ferroelectric/Dielectric Double Gate Insulator Spin-Coated Using Barium Titanate Nanocrystals for an Indium Oxide Nanocrystal-Based Thin-Film Transistor.
abstract: Barium titanate nanocrystals (BT NCs) were prepared under solvothermal conditions at 200 °C for 24 h. The shape of the BT NCs was tuned from nanodot to nanocube upon changing the polarity of the alcohol solvent, varying the nanosize in the range of 14-22 nm. Oleic acid-passivated NCs showed good solubility in a nonpolar solvent. The effect of size and shape of the BT NCs on the ferroelectric properties was also studied. The maximum polarization value of 7.2 μC/cm(2) was obtained for the BT-5 NC thin film. Dielectric measurements of the films showed comparable dielectric constant values of BT NCs over 1-100 kHz without significant loss. Furthermore, the bottom gate In2O3 NC thin film transistors exhibited outstanding device performance with a field-effect mobility of 11.1 cm(2) V(-1) s(-1) at a low applied gate voltage with BT-5 NC/SiO2 as the gate dielectric. The low-density trapped state was observed at the interface between the In2O3 NC semiconductor and the BT-5 NCs/SiO2 dielectric film. Furthermore, compensation of the applied gate field by an electric dipole-induced dipole field within the BT-5 NC film was also observed.
authors.affiliation: Department of Chemistry, Chonnam National University , Gwangju 500-757, Republic of Korea.
authors.forename: Hien Thu
authors.initials: HT
authors.lastname: Pham
authors.affiliation: School of Materials Science & Engineering, Gwangju Institute of Science & Technology , Gwangju 500-712, Republic of Korea.
authors.forename: Jin Ho
authors.initials: JH
authors.lastname: Yang
authors.affiliation: Department of Chemistry, Chonnam National University , Gwangju 500-757, Republic of Korea.
authors.forename: Don-Sung
authors.initials: DS
authors.lastname: Lee
authors.affiliation: School of Materials Science & Engineering, Gwangju Institute of Science & Technology , Gwangju 500-712, Republic of Korea.
authors.forename: Byoung Hun
authors.initials: BH
authors.lastname: Lee
authors.affiliation: Department of Chemistry, Chonnam National University , Gwangju 500-757, Republic of Korea.
authors.forename: Hyun-Dam
authors.initials: HD
authors.lastname: Jeong
keywords: barium titanate; ferroelectricity; indium oxide nanocrystal; nanocrystal; nanocrystal dielectric; thin film transistor