Parameters required to simulate electric characteristics of SiC devices for n-type 4H–SiC

Abstract

In order to obtain some of the parameters required to simulate the electric characteristics of silicon carbide (SiC) power electronic devices in a wide temperature range from startup temperatures (⩽30°C) to steady-operation temperatures (⩾200°C), we discuss the dependence of the two donor levels on the total donor density (ND) as well as the dependence of the electron mobility on the total impurity density (Nimp) and operating temperature (T) in the n-type 4H–SiC. The temperature-dependent electron concentration n(T) and electron mobility μn(T) in the n-type 4H–SiC epilayers with several nitrogen-doping densities are obtained from the Hall-effect measurements. By the graphical peak analysis method (free carrier concentration spectroscopy: FCCS) without any assumptions regarding the donor species, the two types of donor species are detected from n(T). Moreover, the energy level and density of each donor species are determined by the FCCS. Using these results, we obtain the parameters with which the dependence of each donor level on ND can be simulated. Using μn(T) at T>250K, moreover, we obtain the parameters with which the dependence of the electron mobility on Nimp and T can be simulated.