Comparison of nitrogen incorporation in SiO2/SiC and SiO2/Si structures

The nitrogen content of SiO2/SiC (4H) structures annealed in NO and N2O has been measured using nuclear reaction analysis. Samples were annealed in (NO)-N-15-O-18 or (N2O)-N-15 at 1000 degrees C at a static pressure of 10 mbar for either 1 or 4 h. Annealing in N2O incorporates similar to 10(13) cm(-2) of N and annealing in NO incorporates similar to 10(14) cm(-2), both of which are an order of magnitude lower than in SiO2/Si. In the NO anneal, N is predominantly incorporated near the SiO2/SiC interface with an atomic concentration of similar to 0.5%. As in the nitridation of SiO2/Si, two features are observed in SiO2/SiC after the NO anneal: a surface exchange of O in the oxide with the gas phase and NO diffusion and reaction at the interface. The surface exchange reaction in SiO2/SiC is similar to SiO2/Si, but there is a large difference in the incorporation of N at the interface. (C) 2000 American Institute of Physics. [S0003-6951(00)03605-6].