Growth of undoped GaAs single crystal by pulling-down method

Undoped GaAs single crystal has been grown in PBN crucibles by the pulling-down method. The temperature profile of the furnace was optimized with a narrow melting zone and a small temperature gradient at the solid-liquid interface. Quartz ampoules were used to protect the evaporation of As during the growth and the deformation of the ampoule was discussed as a function of temperature, time and pressure differential. A 056 mm X 70 mm GaAs crystal with nearly 100 % single crystalline yield was obtained. X-ray rocking curve analysis revealed the excellent crystalline quality. The average EPD and electrical properties of the crystal were tested comparable to those of the crystal produced by the VGF method. Therefore, the pulling down method was a feasible approach for GaAs crystal production.