Abstract: A new type of high temperature crystal growth furnace has been designed and fabricated with the structure of heat-exchange method (HEM) combined with temperature gradient technique (TGT). Such design could solve the problem of crucible pollution at high temperature and the insufficiency of crystal driving force that derived from distribution of heat. 2 inch Sc₂O₃ crystal is grown and presented in this work, which is recognized as the largest sesquioxide crystal in size. The Sc₂O₃ crystal is colorless and transparent with no crack on the surface and no bubbles or other macro-defects inside of the bulk. The size of bulk Sc₂O₃ crystal is measured to be φ55 mm×50 mm, 40 mm of which is in equal-diameter growth while the rest 15 mm belongs to shouldering part. (222) and (444) peaks are observed in the the XRD pattern of bulk Sc₂O₃ crystal, which indicates to be single phase. X-ray rocking curve (RC) shows good crystalline quality and FWHM of RC peak at 15.76° is determined to be 113″.

Key words: Sc₂O₃ crystal, sesquioxide crystal, heat exchange method, temperature gradient technique