Pyroelectric Infrared Sensor Using PbTiO<SUB>3</SUB> Ceramics

Abstract

(Pb, Ca) ((Co1/2W1/2) Ti) O3 ceramic pyroelectric properties have been studied by changing the Ca concentration. With an increase in Ca concentration, the pyroelectric coefficient P and the figure of merit Fv increased and reached 4.43×10-8C cm-2°C-1, and 0.61×10-10C cm J-1, respectively. Pyroelectric properties have been improved to twice the values for the PbTiO3 ceramics. Ca introduction into PbTiO3 ceramics exerts a great influence on the pyroelectric properties.The infrared sensor using this ceramic has been fabricated by hybrid IC technique. The low temperature fired ceramic substrate was used by the advantage of its remarkably low thermal conductivity. The sensor can operate without the load resistance of the pyroelectric element. The maximum responsivity Rv value versus chopping frequency is obtained i a less than 1 Hz frequency range. Responsivity Rv and specific detectivity D* are 780 V/W and 1.1×108cm √Hz/W at 1 Hz, respectively. The sensor is applicable for human body sensing.