Rapid thermal processing (RTP) has been evaluated as an alternative to conventional furnace technique for oxynitridation of 4H-SiC. Nitrous oxide (N2O) under atmospheric pressure conditions was used as oxidizing gas. The beneficial effect of high energy photons, coming from the RTP halogen lamps, leads to an enhancement of the N2O molecule dissociation and an augmentation of the diffusion rate of dissociated species in the growing oxide. Compared to classical N2O oxidation, the net effect is not only to increase the growth rate but also to result in dielectrics that exhibit a reduced trapped charge, a more stable oxide/4H-SiC overall structure, and a better (less defective) interface. Further optimization, combined with a better understanding of the N2O rapid thermal oxidation process, should provide new issues for the growth of gate oxides in the SiC microelectronic industry. (C) 2010 The Electrochemical Society. [DOI: 10.1149/1.3363738] All rights reserved.