Yield improvement and advanced defect control-driving forces for modeling of bulk crystal growth

Yield improvement and advanced defect control can be identified as the driving forces for modeling of industrial bulk crystal growth. Yield improvement is mainly achieved by upscaling of the whole crystal growth apparatus and increased processing windows with more tolerances for parameter variations. Advanced defect control means on one hand a reduction of the number of deficient crystal defects and on the other hand the formation of beneficial crystal defects with a uniform distribution and well defined concentrations in the whole crystal. This 'defect engineering' relates to the whole crystal growth process as well as the following cooling and optional annealing processes respectively. These topics were illustrated by examples of modeling and experimental results of bulk growth of silicon (Si), gallium arsenide (GaAs), indium phosphide (InP) and calcium fluoride (CaF2). These examples also involve the state of the art of modeling of the most important melt growth tech niques, crystal pulling (Czochralski methods) and vertical gradient freezing (Bridgman-type methods).