Pb(Zr_(0.3)Ti_(0.7))O_3/PbTiO_3 multilayer thin films for pyroelectric infrared sensor application

摘要

We report on the properties of Pb(Zr_(0.3)Ti_(0.7))O_3/PbTiO_3 (PZT/PT) multilayer thin films for pyroelectric infrared sensor application. The effect of various PZT and PT stacking sequences has been systematically studied. The optimal structure for pyroelectric infrared sensor application is found to be the multilayer 5PZT/4PT thin film which has the PZT and the PT layers deposited alternately. It is characterized that the 5PZT/4PT multilayer thin film has reduced dielectric constant and comparable pyroelectric coefficient and dielectric loss when compared with the pure PZT thin film. The interface induced space charge polarization and "pinched" ferroelectric hysteresis loop of the multilayer thin film have been discussed. A detectivity figure of merit of 2.1 X 10~(-5) Pa~(-1/2) at 30 Hz has been characterized for the 5PZT/4PT thin film, which is better than that of the pure PZT thin film.