Effects of oxidants on the deposition and dielectric properties of the SrTiO3 thin films prepared by liquid source metal-organic chemical vapor deposition (MOCVD)

SrTiO3 thin films are deposited by a liquid source metal-organic chemical vapor deposition (MOCVD). The effects of oxidants on the deposition characteristics and dielectric properties of the films are mainly tested. O2, N2O and O2 + N2O gases are used as the oxidants and the films with Ti-rich and Sr-rich compositions are obtained when O2 and N2O is used, respectively. Deposition of thin initial layer under O2 atmosphere is very effective to obtain large dielectric constant of the SrTiO3 thin film when the main layer is deposited under O2 + N2O atmosphere. The dielectric constants of 40 nm thick SrTiO3 films with thin O2, N2O initial layers and without the initial layers are 235, 145 and 210, respectively.