BEHAVIOR OF RALO3 (R=HO, ER AND DY) DURING CRYSTAL-GROWTH BY THE CZOCHRALSKI METHOD

We have first grown ErAlO3 and HoAlO3 crystals with 15 mm diameter by the Czochralski method, and compared their growth behavior with that o f DyAlO3 grown using the same hot zone with the same structure as that for crystal growth of ErAlO3 and HoAlO3. Although HoAlO3 and ErAlO3 C rystals with length greater than 40 mm and straight bodies were succes sfully grown, growth of DyAlO3 Crystals encountered such difficulties as twisting and separation from the melt under our experimental condit ions. Measurements of absorption spectra showed that DyAlO3 had strong absorption peaks at wavelengths near 1100 nm, which was estimated to correspond to the maximum emissive spectrum from the crucible material . Crystal growth difficulties were explained in terms of heat transfer due to internal radiation through the crystals during growth.