Dielectric Property of PZT Thin Films Doped with PMnN

Abstract

The high piezoelectricity and high mechanical quality factor thin films are very important for the fabrications of micro devices. The Pb(Zrx,Ti1-x)O3(PZT) thin films own high piezoelectricity, however, its mechanical quality factor is small. The proper doping of Pb(Mn1/3,Nb2/3)O3(PMnN) will perfectly improve the mechanical quality of the films. However, the doping of PMnN will change the dielectric property of PZT thin films, and so it’s very necessary to investigate the dielectric property of PZT thin films doped with different ratio of PMnN. In this paper, the Pb(Mn1/3,Nb2/3)O3- PbZrO3-PbTiO3(PMnN-PZT) thin films with different doping ratio of PMnN are deposited by the magnetron sputtering method, and the X-ray diffraction is applied to analyze the structure of thin films, and the relative dielectric constant are characterized by the LCR testing system. The results show that the PMnN-PZT thin films with smaller doping ratio than 20% exhibit polycrstal structure, and the dielectric constant of thin films increase with the doping ratio of PMnN sharply, especially the doped PMnN is smaller than 6 mol percent. All the dielectric constants decrease with the testing frequency, and which have little change if the testing frequency is larger than 2.5kHz.