Distribution of nitrogen and defects in SiOxNy/Si structures formed by the thermal nitridation of SiO2/Si

Abstract

Previously reported nitrogen distributions in SiO₂ films on Si which have been thermally nitrided at 1000 °C have been explained by a kinetic model of the nitridation process which rests upon the effects of interfacial strain. A critical test of this kinetic model is the validity of the predictions regarding nitrogen distributions obtained at other nitridation temperatures. In this work, nitrogen distributions determined via x‐ray photoelectron spectroscopy are reported for samples nitrided at 800 and 1150 °C, and are shown to be consistent with the kinetic model. In addition, the intensity of a fluorine marker is found to correlate with the nitrogen distribution, and is postulated to be related to kinetically generated defects in the dielectric film, consistent with the strain‐dependent energy of formation of defects proposed recently to explain electrical data.