<title>(Mn, Sb)-doped PZT thin films with (La, Sr)CoO3 electrodes for uncooled infrared detectors</title>

Abstract

(Mn, Sb) doped-PZT (PMSZT) thin films have been grown on La<SUB>0.5</SUB>Sr<SUB>0.5</SUB>CoO<SUB>3-(delta</SUB> )/Si and La<SUB>0.5</SUB>Sr<SUB>0.5</SUB>CoO<SUB>3- (delta</SUB> )/LaAlO<SUB>3</SUB> substrates for pyroelectric detector arrays. The La<SUB>0.5</SUB>Sr<SUB>0.5</SUB>CoO<SUB>3(delta</SUB> ) thin films, acting as a bottom electrode and as an atomic template for epitaxial growth of PMSZT, were deposited below 550 degrees Celsius thus allowing for integration with silicon technology. The epitaxial PMSZT thin films was designed to achieve high infrared responsivity using (100) oriented LSCO electrodes. The Ni-Cr/PMSZT/LSCO/Si capacitor-like structures show good ferroelectric properties with a large remnant polarization P<SUB>r</SUB> of 40 (mu) C/cm<SUP>2</SUP>, a spontaneous polarization P<SUB>s</SUB> of 74 (mu) C/cm<SUP>2</SUP>, and a coercive field E<SUB>c</SUB> of 115 kV/cm under an electric field of 650 kV/cm. The PMSZT films have an electrical field breakdown strength in excess of 467 kV/cm, which is much higher than the coercive field. Voltage responsivity R<SUB>v</SUB> of 4062 V/W at 2 Hz and current responsivity R<SUB>i</SUB> of 281 (mu) A/W at 25 Hz was achieved under black body illumination. With CO<SUB>2</SUB> laser illumination at a wavelength equals 10.6 micrometer, an R<SUB>v</SUB> of 4140 V/W at 2 Hz and an R<SUB>i</SUB> of 441 (mu) A/W at 25 Hz was achieved.