1.School of Materials Science and Engineering， University of Shanghai for Science and Technology， Shanghai 200093， China;2.State Key Laboratory of Infrared Physics， Shanghai Institute of Technical Physics， Chinese Academy of Sciences， Shanghai 200083， China;3.Mathematics and Science College， Shanghai Normal University， Shanghai 200234， China;4.State Key Laboratory of Infrared Imaging Materials and Detectors， Shanghai Institute of Technical Physics， Chinese Academy of Sciences， Shanghai 200083， China
Supported by the National Natural Science Foundation of China （11574336， 11991063）， The Strategic Priority Research Program of Chinese Acdemy of Sciences （XD43010200）， STCSM （18JC1420401， 19ZR1465700， 14ZR1446200）
Scanning Capacitance Microscopy （SCM） was applied to obtain the 2-dimensional carrier distribution on the cross-section of planar type InGaAs/InAlAs pixels. The profile of pn junction in the device structure was able to be depicted with high space resolution. Besides， for InGaAs/InP detector， the SCM study helps to disclose the distinct diffusion behavior of p-type impurities in different functional layers. The lateral diffusion speed of zinc in InGaAs absorption layer was decided as 3.3 times than that in the depth direction， which is significantly higher than the lateral to depth ratio of 0.67 in the n-InP cap layer， this could affect both the capacitance and dark current properties of the diode pixels.
ZHANG Shuai-Jun, LI Tian-Xin, WANG Wen-Jing, LI Ju-Zhu, SHAO Xiu-Mei, LI Xue, ZHENG Shi-You, PANG Yue-Peng, XIA Hui. SCM study on the 2D diffusion behavior of p-type impurities in planar InGaAs detectors[J]. Journal of Infrared and Millimeter Waves,2022,41(1):225~231Copy