Formation of polycrystalline silicon with log-normal grain size distribution

Polycrystalline silicon films, prepared by annealing from amorphous precursors, are analyzed by transmission electron microscopy and reveal a logarithmic-normal distribution of grain sizes. Such size distributions also result from various other crystallization processes from non-crystalline phases. The cessation of nucleation due to the finite amorphous reservoir leads to these logarithmic-normal size distributions. The origin of these observed distributions is a result of nucleation and growth, rather than coarsening of crystallites.