Characterization and aging response of the d31 piezoelectric coefficient of lead zirconate titanate thin films

Abstract

The wafer flexure method was used to characterize the d31 coefficients and monitor their aging rates for a number of 52/48 sol-gel and 50/50 rf sputtered PZT films. Aging results showed that the d31 coefficient decreased in a linear fashion with the logarithm of time. The aging rates measured for the sol-gel films were found to be between 4% and 10% per decade with the thickest films tested displaying the smallest rates. Rates were measured at as much as 26% per decade when the sample was poled against the as-deposited polarization and a little as 2% per decade when poled in the preferential direction.