Pyroelectric ceramics for infrared detection applications

Abstract

Pyroelectric and dielectric properties of modified PZT and PZ have been studied for their use in infrared detectors. Various material figure-of-merits for their use in infrared detector are calculated including when the pyroelectric element is placed on heat-sink condition. The results are compared with exiting candidate materials.

Large pyroelectric properties at reduced depolarization temperature in A-site nonstoichiometry composition of lead-free 0.94Na x Bi y TiO3–0.06Ba z TiO3 ceramics

“…Figure 3a-d presents the change of the dielectric properties of poled compositions from A to D as a function of temperature from 20 to 150°C at 1, 10, and 100 (kHz). The relative permittivity (e r ) of all the compositions increases with temperature, which behaves like a typical ferroelectric material [31]. The relative permittivity (e r ) shows a significant increase with the increase in the x, y, and z contents, with values of 396, 597, 893, and 933, respectively, for the Compositions A to D at RT and 1 kHz; therefore, the small variation in start compositions can be responsible for the significant increase in the relative permittivity value [24].…”

Investigation on FR(LT)–FR(HT) phase transition and pyroelectric properties of pulsed laser deposited Pb(Zr0.93Ti0.07)O3 thin films

“…In the past few decades, infrared detection and the thermal imaging have been used for both military and non-military applications; such as night vision, target acquisition, missile guidance, automotive vision enhancement, fire detection and medical diagnostics [1,2]. For these applications, efforts have been made to develop uncooled infrared and imaging devices.…”

“…Lead zirconate titanate (PZT) is a perovskite structure ferroelectric material with excellent piezoelectric, ferroelectric and pyroelectric properties; and these properties can be improved by changing the ratio of Zr/Ti and doping [3][4][5][6]. The Zr-rich (Zr > 90 mol%) PZT has a low temperature rhombohedral (F R(LT) )-high temperature rhombohedral (F R(HT) ) ferroelectric phase transition and a large spontaneous polarization [7,8]; when the F R(LT) -F R(HT) phase transition is induced by temperature, a nonlinear change of spontaneous polarization occurs, and a large pyroelectric coefficient (p) is obtained, which can be used for heat-electric conversion such as infrared detector and thermal imaging [1,2,6,9,10]. When the F R(LT) -F R(HT) phase transition happens, the dielectric constant (e) and dielectric loss (tan d) are low, and therefore the figure of merit, F d , as given by…”

Modified Lead-zirconate-titanate for Pyroelectric Sensors

“…A pyroelectric sensor is made of ceramic material that generates a surface charge when exposed to IR radiation [1][2][3] . As the amount of radiation changes, so does the charge.…”