高熔点稀土倍半氧化钪(Sc_(2)O_(3))晶体的生长

Growth of High Melting Point Rare Earth Sesquioxide Scandium Oxide Crystal(Sc_(2)O_(3))

本文通过自主研发制造新型高温晶体生长炉,并采用热交换-温度梯度法的热场结构,从而克服了高温环境下坩埚污染。调节热场结构并引入循环气,增大了温度梯度并改善了结晶驱动力不足的问题。用热交换-温度梯度法生长了2英寸(1英寸=2.54 cm)级的氧化钪(Sc_(2)O_(3))晶体,这一结果是目前已知的最大尺寸的倍半氧化物单晶。氧化钪晶体呈现无色透明,外形完整、内部无气泡或其他可观察到的宏观缺陷。尺寸为ϕ55 mm×50 mm。其中放肩部分高度15 mm,等径生长部分的高度为40 mm。块状晶体的XRD谱只有(222)与(444)峰,可判定为单晶体,双晶摇摆曲线半高宽(FWHM)为113″,显示较好的结晶性能。

A new type of high temperature crystal growth furnace has been designed and fabricated with the structure of heatexchange 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 Sc_(2)O_(3) crystal is grown and presented in this work,which is recognized as the largest sesquioxide crystal in size.The Sc_(2)O_(3) 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 Sc_(2)O_(3) crystal is measured to beϕ55 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 Sc_(2)O_(3) 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″.