CHARACTERISTICS OF PYROELECTRIC SENSORS OF POLYUREA FILMS PREPARED BYVAPOR-DEPOSITION POLYMERIZATION

Pyroelectric infrared (IR) sensors were fabricated from aromatic polyu rea by vapor deposition polymerization. Voltage sensitivity (R(v)), no ise voltage, and detectivity (D(500,1,1)) of a sensor fabricated on a glass substrate were 2.6 V W-1, 0.35 mu V, and 3.3 X 10(6) cm Hz(1/2) W-1, respectively. R(v) and D were increased by improving thermal in sulation and thermal absorption efficiency, and by employing a multi-p yroelectric layer structure. An IR sensor fabricated on a thermally in sulated Si wafer had better frequency characteristics than a sintered LiTaO3 ceramic sensor. The rise time of the sensor was about 6 ms. A p yroelectric linear array of 128 sensor elements fabricated on a therma lly insulated Si wafer showed an average voltage sensitivity and detec tivity of 4000 V W-1 and 1 X 10(6) Cm Hz(1/2) W-1, respectively.