In this article an additional annealing step was used to increase the quality of gate dielectric layers on silicon carbide obtained by thermal oxidation. The mixture of POCl3, N-2 and O-2 gases was used within temperature range of 950 degrees C-1100 degrees C. Abnormal oxide growth rate was observed during the annealing process. Significant improvement of trap density was achieved however the best results were obtained for lower range of annealing temperatures (950 degrees C-1000 degrees C). (C) 2015 Elsevier B.V. All rights reserved.