On the nature of crystal growth from the melt

The theory of interface motion as applied to crystal growth by Cahn and his coworkers is examined in detail. This theory, as derived, applied to systems which can have a second order phase transformation but not to liquid-solid or vapor-solid phase transformations which are first order. In this paper, the formalism of the theory is applied to these first order phase transformations. Reasonable agreement with experiment still cannot be obtained. This is because the molecular configuration of the interface is averaged out in the theory by considering a diffuse interface, rather than taking it into account properly in calculating the growth rate. Experimental data on crystal growth have been accumulated and analyzed. It is concluded from this analysis that the theory of Jackson on interface roughness qualitatively predicts crystal growth morphology. Most of the quantitative data on crystal growth are, however, of questionable reliability or are not sufficiently complete for detailed comparison with theory. None of the existent theories of crystal growth can account for these data.