A Study of High-sensitivity (Pb,Ca)TiO3 Pyroelectric Thin Film Infrared Thermal Array Image Sensor

• Main Authors: Chang-Lin Wu, 吳昌陵
• Other Authors: Chung-Cheng Chang
• Format: Others
• Language: en_US
• Published: 2008
• Online Access: http://ndltd.ncl.edu.tw/handle/89526074781932787196

碩士 === 國立臺灣海洋大學 === 電機工程學系 === 96 === In this experiment, the pyroelectric Pb0.7Ca0.3TiO3, (PCT) film is deposited on the silicon substrate through the Radio-Frequency Magnetron Sputtering System and the integrated pyroelectric thin film infrared image detectors with three different MOSFET structures are fabricated and the measurement results of relevant characteristics are compared. At last, the measurement and analyses of thermal image is made with the finished pyroelectric MOSFET infrared array detector. From the measurement of I-V characteristic curve for three different detectors, it is found that, the separate gms of Pt/PCT/Si, Pt/PCT/ SiO /Si and Pt/PCT/Pt/Ti/SiO /Si are 0.433mA/V, 0.291mA/V and 0.158 mA/V. As regards the PCT film, it shows ideal features after a 15-minute annealing process at a temperature of 650℃ according to the experiments of SEM、AFM and XRD diffraction. For measurement of the electric characteristics of the device, the remanent polarization quantity and the coercive field are 18.147μC/cm2 and 50kV/cm2respectively for PCT thin film. The maximal pyroelectric coefficient arrives at 1.23�e10-4 C/m2K at a temperature of 200℃. For characteristics of the devices, it shows a maximal voltage response value at the response frequency of 5Hz, 1718.02 (V/W) for Pt/PCT/Si, 1030.94 (V/W) for Pt/PCT/SiO /Si and 865.52 (V/W) for Pt/PCT/Pt/Ti/SiO /Si. The maximal normalized detectivity for those three different devices is 7.33 105 (cmHz1/2W-1)、6.19 105 (cmHz1/2W-1) and 6.61 105 (cmHz1/2W-1) with the measured frequency of maximal specific detectivity at 40Hz, 40Hz and 15Hz respectively. From the above results, we have fabricated two-dimensional 8 × 8 pyroelectric infrared image detector.