Schotky Barrier Height and Calculation of Voltage–Current Characteristics of Al/n-(SiC)1–x(AlN)x Diodes And 4H–SiC Heterojunctions

Abstract

The Schottky barrier heights in the М/n-(SiC)1–x(AlN)x systems are obtained on the assumption of a high density of surface states in the region of the metal (M) – SiC–AlN-solid solution contact. Current–voltage (I–V) characteristics of the Al/n-(SiC)1–x(AlN)x diodes are calculated. It is shown that at moderate concentrations of surface states (c ≈ 4–8), the Schottky barrier height ФxB(с) of these diodes is close to the heterojunction potential barrier Фxg, which is the reason for the known similarity in the behavior of the corresponding I–V characteristics. The role of the ideality factors in the behavior of the I–V characteristics is analyzed. The obtained values of the Schottky barrier heights are in accordance with experimental data.