Free-standing films of PbSc0.5Ta0.5O3 for uncooled infrared detectors

Highly textured PbSc0.5Ta0.5O3 (PST) films were grown on (111) Pt/Si by the sol-gel technique. The PST films were subsequently lifted off the silicon substrate using reactive ion etching. A 40%-50% increase in dielectric cons tant and pyroelectric coefficient was observed for suspended films compared to those properties of the PST films on a Si substrate. Typical values of the pyroelectric coefficient were measured to be 20-45 nC/(cm(2) K) for 200 -300 nm thick PST films. The loss tangent values were below 0.02 (at 10 kHz ), and the leakage current density was as low as 2-3x10(-8) A/cm(2) at 1 V bias. (C) 2001 American Institute of Physics.