Convection in melts and impurity distribution in semiconductor crystals

Impurity distributions in semiconductor melts and crystals grown from these melts ore experimentally and numerically studied on an example of Ga-doped Ge crystals. It is shown that inhomogeneous dopant distribution is observe d in the form of striations and is caused by the convective flows in the me lt and their nonstationary rearrangement in the vicinity of the crystalliza tion front. The character of heat and mass transfer under the microgravity conditions is predicted. The necessity of precision experiments under terre strial and, especially, space conditions is emphasized. (C) 2000 MAIK "Nauk a/Interperiodica".