GaAs単結晶成長への磁場印加の効果(<特集>バルク成長)

抄録

Effects of applying magnetic field on GaAs crystal growth by LEG technique are reviewed. Temperature fluctuation in GaAs melt was continuously decreased as the vertical magnetic field strength increased from 0 Oe to 7000 Oe. Irregular striations with strong contrast in LEG crystal were reduced at 3000 Oe, but striations with strong contrast reappeared in the crystal grown at 6000 Oe. The shape of solid-liquid interface changed from convex to flat, and the length of slip-dislocation became shorter by applying magnetic field. Distribution of indium concentration along the axial direction was not remarkably changed even at 6000 Oe. The difference of indium concentrations between at the center region and at the peripheral region became larger as the magnetic field strength increased. The strations in IR topographic image which were generated by microscopic fluctuation of EL2 concentration were also reduced at 3000 Oe. It was found that the cellular growth of In-doped GaAs was suppressed, and that the yield was significantly improved by applying magnetic field.