BST Thin Films Of Uncooled Pyroelectric Infrared Cell Structure Design And Performance Of The Detector

In this paper, the design and measurements of single-element infrared detectors based on (Ba, Sr)TiO₃ (BST) pyroelectric thin films were investigated.The principles of pyroelectric infrared detector were analyzed. The comparison between the hybrid and monolithic infrared detector was given, and the performances of several common thermal insulation structures were discussed. Based on these analyses, a planar thermal insulation structure combining the porous SiO₂ thin film and transient SiO₂ thin film was given, and the parameters were detail listed. The planar structure not only is compatible with the standard semiconductor fabric technology, but also improves the mechanical strength of the infrared detector.A measurement system has been established to evaluate the BST thin film single-element infrared detectors. The results indicated that the measurement system is accurate and reliable.Based on the measurement apparatus, the influences of the chopping frequency, the radiation temperature and the detection distance to the detector performances were studied. The measurement results show that the noise of the system(S_N) is 0.2mV/Hz^1/2, the voltage responsivity(Rv) is 2.8^*10⁵V/W and the detectivity(D^*) is 4.3^*10⁷cmHz^1/2/W at the chopping frequency of 100Hz, the radiation temperature of 1027K and the testing distance of 11.5cm.