Influence of MgO and ZrO2 buffer layers on dielectric properties of Ba(Zr0.20Ti0.80)O3 thin films prepared by sol–gel processing

Ba(Zr0.20Ti0.80)O3 (BZT) thin films are deposited on Pt(1 1 1)/Ti/SiO2/Si, MgO and ZrO2 buffered Pt(1 1 1)/Ti/SiO2/Si substrates by a sol–gel process. The BZT thin films directly grown on Pt(1 1 1)/Ti/SiO2/Si substrates exhibit highly (1 1 1) preferred orientation, while the films deposited on Pt(1 1 1)/Ti/SiO2/Si substrates with MgO and ZrO2 buffer layers show highly (1 1 0) preferred orientation. At 100 kHz, dielectric constants are 417, 311 and 321 for the BZT thin films grown on Pt(1 1 1)/Ti/SiO2/Si, MgO and ZrO2 buffered Pt(1 1 1)/Ti/SiO2/Si substrates, respectively. The difference in dielectric properties of three BZT films can be attributed to the series capacitance effect, interface conditions and their orientations.