XPS characterization of tungsten-based contact layers on 4H–SiC

Abstract

Annealed W (WN)/4H–SiC interfaces have been compared on the basis of X-ray photoelectron spectroscopy (XPS) studies. The 1200°C annealed W (WN)/4H–SiC structures are characterized by intense interface reactions leading to tungsten carbide and tungsten silicide formation in the contact layers. The 800°C annealed WN/4H–SiC structure exhibits a chemically inert interface, and the 800°C annealed WN/4H–SiC contact is found to be of a Schottky type with a barrier height of 0.94 eV and an ideality coefficient of 1.09.