The Bubble Method: A Tool for Growth Morphology Studies of the Crystal-Melt Interface

Abstract

Bubble method and gold decoration technique are applied to the observation on an atomic scale of crystal-melt interfaces of pure and mixed alkali halide crystals grown from melt by the Czochralski method. An attempt is made to answer some questions regarding the possibilities and the limits of the bubble method. It is shown that, although growth morphologies unaltered by the withdrawal of the melt from the interface can only be observed in a restricted number of cases, the understanding of the intersection between growing surface and retiring melt helps the interpretation of more complex surface features. Information regarding microscopic wetting of different crystallographic faces and concave edges can thus be obtained.