BI4TI3O12 FERROELECTRIC THIN-FILM ULTRAVIOLET DETECTORS

Bi4Ti3O12 (BiT) ferroelectric thin films were used as photoconductive or photovoltaic ultraviolet detectors. The maximum of the spectral dis tribution lies around 370 or 390 nm, depending on whether the incident light is continuous or modulated. The maximum current responsivity ob tained for the films annealed at 700 degrees C is about 0.01 A/W. The specific detectivity is 5.5 x 10(8) cm W-1 Hz(1/2) at a modulation fre quency of 20 Hz. The frequency characteristics of the photovoltaic sig nal measured in modulated light suggests a 1/f frequency dependence of this signal. (C) 1998 American Institute of Physics.