Peculiarities of the dislocation generation and propagation in Czochralski Si wafers after various heat treatments were studied by using the 4-point bending method. It was shown that heat treatment strongly influenced the mechanical properties of the wafers. Annealing at 450C led to substantial strengthening of the wafers in comparison with the as-grown state. Multi-step annealing in regimes of intrinsic getter formation in wafers caused a substantial decrease in the critical stresses for the generation of dislocations, and increased their mobility. It was shown that both O precipitates and precipitate–dislocation clusters that formed in the wafer bulk during the multi-stage thermal treatments were effective centers for the heterogeneous generation of dislocations by thermal or mechanical stresses.

Generation and Motion of Dislocations in Silicon Wafers Subjected to Multi-Step Annealing. M.V.Mezhennyi, M.G.Milvidskii, V.Y.Reznik, R.J.Falster: Journal of Physics - Condensed Matter, 2002, 14[48], 12909-15