Influence of MgO and ZrO_2 buffer layers on dielectric properties of Ba(Zr_(0.20)Ti_(0.80))O_3 thin films prepared by sol-gel processing

摘要

Ba(Zr_(0.20)Ti_(0.80))O_3 thin films are deposited on Pt(111 )/Ti/SiO_2/Si, MgO and ZrO_2 buffered Pt(l 1 l)/Ti/SiO_2/Si substrates byasol-gel process. The BZTthin films directly grown on Pt(111)/Ti/SiO_2/Si substrates exhibit highly (111) preferred orientation, while the films deposited on Pt(11 l)/Ti/SiO_2/Si substrates with MgO and ZrO_2 buffer layers show highly (110) preferred orientation. At 100 kHz, dielectric constants are 417,311 and 321 for the BZT thin films grown on Pt(111 )/Ti/SiO_2/Si, MgO and ZrO_2 buffered Pt(111)/Ti/SiO_2/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.