| 摘要 |
PURPOSE:To produce a star sapphire having high quality comparable to natural star sapphire, easily, by subjecting a sapphire crystal composed mainly of Al2O3 and containing titanium as a colorant to CVD or plasma CVD treatment in FeCl3 atmosphere. CONSTITUTION:A sapphire crystal composed mainly of Al2O3 and containing at least titanium (e.g. TiO2) as a colorant is subjected to CVD or plasma CVD treatment in FeCl3 atmosphere to produce a star sapphire. The control of color tone and the elimination of crystal defect caused by the dissolution of iron oxide in solid crystal during the crystal growth, which are impossible by conventional synthesis, can be carried out, and a star sapphire having a quality comparably high to natural jewel exhibiting clear star effect can be produced easily by this process. |
