HIGH QUALITY N-TYPE GASA SINGLE CRYSTAL GROWING METHOD BY HORIZONTAL BRIDGEMAN

摘要

The temp. region of a melting part of GaAs and end part of ampoule has 1240-1250 and 1100-1050 deg.C respectively. A temp. distribution at 1230-1240 and 1240-1250 deg.C is controlled to below 5 deg.C/cm and 1 deg.C/cm. A growth velocity at seed and shoulder and ingot part is effectively controlled to 3 mm/hr and 5 mm/hr and 4 mm/hr, respectively. A cooling rate at 1200-1000 and 1000-800 and below 800 deg.C is controlled to 1 deg.C/min and 2 deg.C/min and 10 deg.C/min. When a doping concentration of silicone has (3×5)×1018 cm-3, n-type ingot of high quality is prepared.