Effects of post-deposition annealing temperature on metal-organic decomposed lanthanum cerium oxide film as metal reactive oxide layer on 4H-SiC

Investigation of metal-organic decomposed LaxCeyOz film was performed on n-type 4H-SiC substrate by varying post-deposition annealing (PDA) temperature from 400 to 1000 °C. The LaxCeyOz acting as a metal reactive oxide layer was demonstrated, explained, and justified via X-ray photoelectron spectroscopy (XPS) through its effect in performing catalytic oxidation of the substrate with temperature as low as 400 °C and the removal of excess carbon, originated from the substrate itself, accumulated at the oxide/4H-SiC interface via formation of CO. Williamson-Hall approach has revealed an increment in crystallite size for LaxCeyOz with decreasing microstrains as PDA temperature increased. High resolution transmission electron microscopy showed the formation of a distinct amorphous interfacial layer in between the bulk oxide and SiC substrate. XPS analysis proved that the bulk oxide with a mixture of amorphous and crystalline regions was comprised of an intermixing of La, Ce, O, C, and La, Ce, O, Si, C elements while interfacial layer consisted of La, Ce, O, Si, and C elements.