Characterization of Ba(Zr_0.2Ti_0.8)O₃ thin films deposited by RF-magnetron sputtering

We investigated the structural and electrical properties of the Ba(Zr_xTi_1-x)O₃ (BZT) thin films with a mole fraction of x=0.2 and thickness 150nm for application in a multilayer ceramic capacitor (MLCC ). BZT films were prepared on Pt/SiO₂/Si substrates at various substrate temperatures using an RF-magnetron sputtering system. When the substrate temperature was above 500°C, we could obtain multi-crystalline BZT films oriented in 〈110〉, 〈111〉, and 〈200〉 directions. Crystallization of the film and a high dielectric constant were observed with increase of substrate temperature. Capacitance of the film deposited at high temperature is more sensitive to the applied voltage than that of the film deposited at low temperature. This paper reports surface morphology, dielectric constant, dissipation factor, and C-V characteristics for BZT films deposited at three different temperatures. The BZT film deposited at 400°C shows stable electrical properties but a small dielectric constant for MLCC applications.