Effect of Thermal Stress on Domain formation and Electrical Properties of Pb(Zr,Ti)O3 Epitaxial Thin Films deposited on Si and YSZ Substrate by the CSD method
We investigated the orientation and substrate dependency of PZT thin films deposited upon (001), (110), (111) oriented SRO/buffer/Si and SRO/buffer/YSZ substrates. During the cooling process, thermal stress applied to PZT thin films by the difference of thermal expansion coefficients between the thin film and substrate, control the domain ratio and c/a values of the thin film, also relate to the electrical property. Due to the existence of adomain, which does not contribute to the polarization of tetragonal PZT, the order of the Pr values is (111)>(101)/(110)>(001)/(100). Furthermore, the Pr value of the PZT thin film on YSZ substrates is higher than that of PZT on Si substrate, because the higher thermal expansion coefficient of YSZ substrate than that of Si substrate makes larger c-domain ratio and higher c/a values.