1.State Key Laboratories of Transducer Technology， Shanghai Institute of Technical Physics， Chinese Academy of Sciences， Shanghai 200083， China;2.Key Laboratory of Infrared Imaging Materials and Detectors， Shanghai Institute of Technical Physics， Chinese Academy of Sciences， Shanghai 200083， China;3.University of Chinese Academy of Sciences， Beijing 100049， China
Supported by National Natural Science Foundation of China （61704180，62175250）
Metal-Insulator-Semiconductor （MIS） capacitors were fabricated on In0.74Al0.26As/In0.74Ga0.26As/InxAl1-xAs heterostructure multilayer semiconductor materials. SiNx and SiNx/Al2O3 bilayer were applied as insulating layer to prepare MIS capacitors respectively. High-resolution transmission electron microscopy （HRTEM） and X-ray photoelectron spectroscopy （XPS） measurements indicated that， compared with SiNx deposited by inductively coupled plasma chemical vapor deposition （ICPCVD）， Al2O3 deposited by atomic layer deposition （ALD） can effectively suppresses In2O3 at the interface between Al2O3 and In0.74Al0.26As. According to the capacitance-voltage （C-V） measurement result of MIS capacitors， the fast interface state density （Dit） of SiNx/Al2O3/In0.74Al0.26As was one order of magnitude lower than that of SiNx/In0.74Al0.26As. Therefore， it can be concluded that Al2O3 deposited by ALD as a passivation film can effectively reduce the interface state density between Al2O3 and In0.74Al0.26As， thereby reducing the dark current of p-In0.74Al0.26As/i-In0.76Ga0.24As/n-InxAl1-xAs photodiodes.
WAN Lu-Hong, SHAO Xiu-Mei, LI Xue, GU Yi, MA Ying-Jie, LI Tao. Interfacial properties between Al2O3 and In0.74Al0.26As epitaxial layer on MIS capacitors[J]. Journal of Infrared and Millimeter Waves,2022,41(2):384~388Copy