The specific features in the generation and motion of dislocations in Si single-crystal wafers after different heat treatments were investigated by the four-point bending technique. It was demonstrated that annealing of Si single-crystal wafers at a temperature of 450C leads to their substantial hardening as compared to the post-growth state. The O-containing precipitates and precipitate dislocation pileups formed in the Si wafer bulk during multistage heat treatment were efficient heterogeneous nucleation sites of dislocations under the action of thermal or mechanical stresses. It was found that the multistage heat treatment of the Si wafers under conditions providing the formation of an internal getter within their bulk results in considerable disordering of the wafer structure. The inference was made that the formation of the defect state in the crystal lattice of Si and the strength characteristics of Si wafers substantially depend on the temperature–time schedules of the low-temperature stage of multistage heat treatment.

Specific Features in the Generation and Motion of Dislocations in Heat-Treated Silicon Wafers. M.V.Mezhennyĭ, M.G.Milvidskiĭ, V.F.Pavlov, V.Y.Reznik: Physics of the Solid State, 2002, 44[7], 1284-90