Authors: S Ha YS Lee YP Hong HY Lee YC Lee KH Ko DW Kim HB Hong KS Hong
Publish Date: 2005/02/01
Volume: 80, Issue: 3, Pages: 585-590
Abstract
Reactively rfsputtered Bi2O3ZnONb2O5 BZN thin films were prepared on Pt111/TiO2/SiO2/Si with substrate heating The effects of substrate heating on the structures morphologies dielectric properties and voltagetunable dielectric properties of the films were investigated With heating the BZN thin films could be deposited in crystalline form as the cubic pyrochlore phase The amounts of secondary phases such as zinc niobate and bismuth niobate depended on the substrate temperature The more compounding of the BZN crystalline phase proceeded at deposition the less formation of secondary phases and stoichiometric change occurred after postannealing Therefore improvement of the dielectric constant and tunability of thin films by grainsize enlargement might be possible with proper substrate heating and postannealing The BZN thin films sputtered with a substrate temperature of 550 °C and annealed at 800 °C showed a maximum tunability of 265 at a dc bias field of 1000 kV/cm and measurement frequency of 1 MHz
Keywords: