Pyroelectric and electro-optic properties of sol-gel and dual ion beam sputtered PLZT thin films

The deposition of ferroelectric films using sol-gel and dual ion beam sputtering (DIBS) has been demonstrated. In the DIBS process, the presence of active oxygen has been found to be essential to the formation of perovskite PLZT (La-doped lead zirconate titanate) films. Electrooptic (EO) and pyroelectric effects have been observed in these films. A large quadratic EO efficient of 2.1×10^-16 m ²/V² was observed in reflection mode for PLZT (28/0/100), but this could not be repeated in a transmission mode, presumably because birefringence and thickness changes work in opposite senses. Peak pyroelectric coefficients of 400 μmC/m²K have been observed for PLZT (0/0/100) and (7/0/100) films. Sol-gel has produced PLZT (0/50/50) and (0/30/70) films with similar properties and has shown potential for film formation at temperatures as low as 450°C. The results reported here are encouraging with respect to the goal of fully integrating uncooled infrared-detector elements on silicon readout circuitry