Influence of Li+ dopants on the properties of the ZnO piezoelectric films

ZnO piezoelectric films with the preferred 002-orientation were prepared by sol-gel method. The annealing temperature was 600◦C and the resistivity of the ZnO film was 1 × 106 ·cm. Li2CO3 and LiCl were added respectively into ZnO precursor as source of Li+-ion. The molar ratio of [Li+]/[Zn2+] was 0.05. It is observed that the annealing temperature for forming preferred 002-orientation of ZnO films decreases from 660 to 550◦C after Li2CO3 being doped. When Li2CO3 and LiCl are doped, the resistivity of ZnO films increases to 108 ·cm and 109 ·cm, respectively, with an annealing temperature of 550◦C. When annealing temperature is 600◦C, the resistivity of the ZnO film with LiCl dopant increases to 107 cm. The influence mechanism of the two dopants on the properties of the ZnO films is analyzed. C 2005 Springer Science + Business Media, Inc.