Researches On The Measurement And Application Of Infrared Detector Low-Frequency Noise

Infrared (IR) detector is the core component of IR detection system. In output signals which include the device's voltage or current, the noise has a direct effect on the detectability and sensitivity of detector. Therefore, reducing noise can improve the performance of detector. Low-frequency noise influences the performance of detector, besides, it is able to estimate devices'quality and reliability, and diagnose devices'defect by analyzing. Consequently, the investigation on low-frequency noise of IR detector is significant. Now, the research on low-frequency noise of native IR detector is initial stage, the complicated way to measuring noise, the single goal of study that is for lessening noise. In order to study the low-frequency noise of IR detector deeply, develop the physical model of IR detector's low-frequency noise and the system for measuring and analyzing low-frequency noise. Moreover, give a low-frequency noise characterized way of IR detector's defect and reliability on the basis of the actual measurement and analysis of IR detector's noise.Firstly, derive the physical models of 1/f noise and g-r noise that based on the principal characteristics of 1/f noise, ohm's law and the expression of basic physics parameter (resistor, current and voltage). Secondly, make a plan for measuring noise based on the analysis of IR detector's low-frequency noise. Thirdly, in terms of the plan, develop the system which contain the measuring soft and the testing circuit for measuring and analyzing IR detector's noise, and give concrete testing ways. Fourthly, the developed system is used for researching on the major mechanism, the voltage's feature and temperature's feature of low-frequency noise. Fifthly, verify the accuracy of noise physical models through the comparison of theoretical calculation with actual measuring results. Finally, in accordance with verified physical models of noise, make the characterized model of IR detector's defect and reliability, and calculate characterized parameters of defect which include the density of surface defect, deep-level defect activate energy, degeneracy factor, capture section of carrier and so on.The accomplished investigations on noise of IR detector give a new way of screening IR detectors'reliability and a direction to technical devise, in the mean time, which establish a theoretical basis for the study of IR arrays detectors'noise.