Czochralski growth of GeSi bulk alloy crystals

Bulk crystals of Ge1-xSix alloys of the composition range 0 < x < 1 were grown by the Czochralski method with the pulling rate 0.5-8 mm/h. Fully grown single crystals of large size were obtained with composition x < 0.15 and x > 0.85. Crystals with intermediate composition changed to polycrystalline due to the constitutional supercooling. The hetero-seeding process by using an Si or Ge crystal was investigated in terms of solute segregation. By infra-red spectroscopy, a large number of oxygen atoms were deduced to be included in the grown alloys. The velocity for single crystal growth and the distribution coefficient in the whole composition range of GeSi alloy are discussed. (C) 1999 Elsevier Science B.V. All rights reserved.