In-situ observation of HB GaAs crystal growth

In-situ monitoring of horizontal Bridgman (HB) growth of GaAs crystals through the furnace window can reveal whether the growth condition is good or not. Good growth conditions are characterized by straight melt/crystal interface and (111) facet growth striations on the grown crystal surface. Abnormal growth conditions including twinning, lineaging and polycrystallizing in the growing crystals usually show curved or irregular-shaped melt/crystal interface and various slanted lines distributed over the crystal surfaces. The monitoring process can spot these defective conditions in the early stage of their formations, and growth parameters thus can be adjusted in real time for correction. It provides a convenient way to help understand the relations between growth parameters and defects formation. The yield and quality of the M2T-HB grown crystals are both increased by this method.