A study has been made of the macroscopic structure of the liquid–solid interface which exists during growth of silicon crystals by the Czochralski method. In two crystals the interface was seen to contain a (111) facet. The development of such facets is discussed with reference to current crystal growth theories.

The equilibrium distribution coefficient of boron in germanium was found to be 12.2. The variation with growth rate was interpreted in terms of a theory by Burton, Prim, and Slichter. As the growth rate was increased the width of the diffusion dominated layer initially increased followed by a later decrease. This was due to a change from a thermally produced melt flow pattern to a hydrodynamically produced pattern. The results show that a slow growth rate and a high rotation rate should be used to obtain equilibrium distribution coefficients.

An indirect method has been used to obtain a value for the distribution coefficient of oxygen in germanium. The method requires a knowledge of the distribution coefficient of aluminum in germanium and also information upon the state of oxidation of aluminum in germanium. If aluminum oxide in liquid germanium is assumed present as Al2O3 then a distribution coefficient k for oxygen in germanium of 0.11 is indicated.

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