A new theoretical model for the description of the degradation of silicon nitride films under high temperature annealing

A macroscopic kinetic model of the defect transformation and decomposition of he SiNx:H films during high temperature annealing has been considered. The set of equations describes the kinetic model taking into account the breaking of (SixNy)Si:H and (SixNy)SiN:H bonds, formation of dangling bonds, formation of mobile hydrogen atoms and molecules, and formation of nitrogen atoms, diffusion of the mobile species to the surface and their evolution from the film. Numerical simulation of the equations has allowed to find the redistribution inside SiNx:H film of ‘free’ hydrogen and nitrogen, (SixNy)Si:H and (SixNy)SiN:H, and dangling (SixNy)Si and (SixNy)SiN bonds caused by high temperature treatment as a function of the annealing time. The results of numerical simulation have been compared with experimental data and qualitatively agree with an earlier proposed model [1] which did not consider nitrogen evolution from the film.