Research And Preparation Of Pyroelectric Infrared Sensor Arrays

Pyroelectric infrared detectors have more advantages than other detectors and have been studied hotly recently. This paper is aimed at the preparation of pyroelectric thin and thick film infrared sensor arrays. Focusing on this spot, PLT pyroelectric thin films are prepared, the fabrication processing and structure design of PLT film infrared sensor arrays are researched including the micro-pattern etching techniques and the etching mechanisms of the PLT films, the electrodes and Si sacrificial layer. Besides, the PLCT thick films are prepared by tape-casting technique and the PLCT thick film infrared sensor arrays are fabricated. Their electrical performances and readout signals are tested. The main researches are listed as follows:PLT pyroelectric thin films are prepared by Sol-Gel technique. 128×128 PLT film infrared sensor arrays are designed. The micro-pattern etching techniques and the etching mechanisms of the PLT films, the electrodes and Si micro-bridges are studied. And the micro-pattern of 128×128 PLT film infrared sensor arrays are etched successfully. The etching mechanisms of anisotropic etching monocrystalline silicon are studied, and the Si micro-bridges are fabricated successfully after being etched in TMAH .PLCT pyroelectric thick films are prepared by tape-casting technique. Tetrathyl orthosilicate is used as binder, and diethyl phthalate and glycerine are used as plasticizer. The perform- ance of PLCT thick film are made through plywood-faced sintering method. The results show that, the mean pyroelectric coefficient in the range of the measured temperature of the PLCT pyroelectric thick film sample is 5.5×10^-8C/cm²K. And at room temperature (20℃) , the pyroelectric coefficient and detectivity figure-of-merits are 5.97×10^-8C/cm²K and 1.00×10-8Ccm/J respectively. At last, the 2×2 PLCT thick film infrared sensor arrays are fabricated. And their electrical performances and readout signals are tested.