The measurement of responsivity of infrared photodetectors using a cavity blackbody
Nong Li, Dongwei Jiang, Guowei Wang, Weiqiang Chen, Wenguang Zhou, Junkai Jiang, Faran Chang, Hongyue Hao, Donghai Wu, Yingqiang Xu, Guiying Shen, Hui Xie, Jingming Liu, Youwen Zhao, Fenghua Wang, Zhichuan Niu
Abstract
Abstract For the measurement of responsivity of an infrared photodetector, the most-used radiation source is a blackbody. In such a measurement system, distance between the blackbody, the photodetector and the aperture diameter are two parameters that contribute most measurement errors. In this work, we describe the configuration of our responsivity measurement system in great detail and present a method to calibrate the distance and aperture diameter. The core of this calibration method is to transfer direct measurements of these two parameters into an extraction procedure by fitting the experiment data to the calculated results. The calibration method is proved experimentally with a commercially extended InGaAs detector at a wide range of blackbody temperature, aperture diameter and distance. Then proof procedures are further extended into a detector fabricated in our laboratory and consistent results were obtained.