Heat flow and D* of multilayer thin film pyroelectric detector

Abstract

The pyroelectric responses of multilayer, thin film pyroelectric detector under both isolated and heat sink boundary conditions are completely analyzed. The multilayer detector is composed of pyroelectric layer/thermal isolation layer/silicon substrate. The analytical result shows that when the thickness of the isolation layer is increased, the detectivity, D* at tow frequencies will be improved, and as the thickness of pyroelectric layer is decreased, the high frequency response becomes better. D* of a detector with 1 /spl mu/m PLZT/10 /spl mu/m porous silica/0.5 mm silicon is higher than that of the detector with 10 /spl mu/m PLZT/1 /spl mu/m porous silica/0.5 mm silicon in a wide frequency range. In order to get a better performance of a multilayer thin film detector, the thicknesses of the two layers should be chosen very carefully. This analysis provides a guide for the preparation of the multilayer thin film pyroelectric detectors.