Non-doped dislocation-free monocrystals of float-zone Si were studied by using transmission electronic microscopy, optical microscopy and X-ray topography. The crystals were obtained with various growth rates (1 to 9mm/min) and were subjected to various kinds of thermal processing. The temperatures at which micro-defects of various types formed were determined experimentally, and the mechanism of transformation of interstitial micro-defects was established. On the basis of the available data, it was established that the formation of micro-defects in Si occurred via 2 independent mechanisms: vacancy and interstitial. As a result of both these mechanisms, D-micro-defects were formed as interstitials agglomerated. It was suggested that a critical value of growth-rate/temperature-gradient described the conditions of emerging (vanishing) vacancy micro-defects. On the basis of these results, a physical model was suggested for the formation of micro-defects in dislocation-free monocrystals of float-zone Si.

Physics of the Formation of Microdefects in Dislocation-Free Monocrystals of Float-Zone Silicon. V.I.Talanin, I.E.Talanin, D.I.Levinson: Semiconductor Science and Technology, 2002, 17[2], 104-13