Effect of Y and Mn doping in Pb(T,Zr)O3 piezoelectric ceramics on the resonant frequency and capacitance changes and aging by thermal shock tests

The effects of Y and Mn-doping in Pb(Zr,Ti)O-3 (PZT) with respect to the resonant frequency changes and the aging phenomena caused by thermal treatment were studied in order to achieve a stable piezoelectric ceramic filter. Good thermal stability as well as a high mechanical quality factor Q(M) were required for the piezoelectric ceramics to fabricate certain types of narrow band monolithic filters. The Cr-doped PZT showed a little aging phenomena in resonant frequency change after thermal shock tests, but Q(M) was not high. The Cr and Mn-doped PZT had a large Q(M) value, but a large amount of resonant frequency change and aging after thermal shock tests. It was observed that the PZT with the addition of Y and Mn has high Q(M) and good temperature stability. These features were suitable for the use in filters and resonators.