Analysis of failure of C-V characteristics of MIS structure with SiO₂ passivation layer deposited on InSb substrate via Raman spectroscopy

Abstract

The effect of interfacial phases on the electrical properties of Au/Ti/SiO 2 /InSb metal-insulator (oxide)-semiconductor (MIS or MOS) structures was investigated by capacitance-voltage (C-V) measurements. With increasing the deposition temperature of silicon oxide from 100 to 350 o C using PECVD, the change in the interfacial phases between SiO 2 and InSb were analyzed by resonant Raman spectroscopy to verify the relation between the breakdown of C-V characteristics and the change of interfacial phases. The shape of C-V characteristics was dramatically changed when the deposition temperature was above 300 o C. The C-V measurements and Raman spectra represented that elemental Sb accumulation resulted from the chemical reaction of Sb oxide with InSb substrate was responsible for the failure in the C-V characteristics of MIS structure.