Fundamental Aspects of High Speed Crystal Growth from the Melt

Abstract

ABSTRACTAdvances in the study of high speed crystal growth from the melt are reviewed, with special emphasis on the fast melting and solidification of silicon achieved by use of Q-switched laser radiation pulses. Rapid melting of amorphous Si is confirmed to yield a liquid undercooled by several hundred Kelvins and, under suitable conditions, explosive crystal growth processes can occur. The latter involve the self-sustaining propagation of melt bands buried within the initially amorphous material. When the highest quench-rate conditions are established melting of even crystalline Si can yield a final amorphous solid phase. This breakdown in crystal growth is orientation dependent and can give regimes of crystal defect formation when amor-phization does not take place. The processes which characterize this limiting growth behaviour are discussed.