Pyroelectric Properties of La- and Mg-Modified PbTiO3 Thin Films

The pyroelectric properties of highly c-axis-oriented lanthanum- and magnesium-modified PbTiO3 (PLMT) thin films were investigated in detail by the method of measuring of static pyroelectric properties. The figures of merit F. M. for voltage responsivity of pyroelectric IR sensors showed higher values in the region of x=0.005-0.010 than those in other regions; in particular, the sample with x=0.010 exhibited the highest F. M. of around 1.05×10-10C·cm/J, around 1.5 times as large as that of the PL10 (PLMT; x=0) sample. In conclusion, thin films with the composition of (1-x)Pb0.9La0.1Ti0.975O3+xMgO, where x=0.010, show a great promise as element materials for pyroelectric IR sensors.