摘要
本文报道了坩埚下降法生长大尺寸白宝石单晶。我们使用大尺寸异型钼坩埚 ,高纯氧化铝原料 ,在中性气氛下 ,结晶区温度梯度为 2 5～ 30℃ /cm ,生长速度为 0 .8～ 1.8mm/h ,生长方向选C面 [0 0 0 1]取向 ,成功生长出直径 80mm ,高度 90mm的完整透明的白宝石单晶 ,在 30 0～ 550 0nm范围内 ,其光学透过率均在 80 %以上。实验中采用高性能保温材料使生长过程所需加热功率由 2 0kW下降到 15kW ,能耗降低达 2 5% ;采用双回路加热系统 ,提高温场稳定性 ,缩短晶体生长周期。晶体的主要缺陷为顶部 (生长后期 )出现有 5～ 10mm淡黄色色带 (经在氧化性气氛中退火后已消除 )和底部有细丝状条纹。
The perfect and full transparent sapphire crystals,80mm in diameter and 90mm in high have been successfully grown by means of vertical Bridgman technique.The two loop heating equipment and Mo crucible 80mm in diameter have been adopted during the growth process.The parameters for crystal growth are typically as follows:temperature gradients next the interface are 25—30℃/cm,dropping rate is 0.8—1.8mm/h,the direction of crystallization is [0001];and energy consuming is 15kW.Their transmission spectra have been measured.It has been found that the main defects in the sapphire crystal are pores,solid and yellow inclusions.Their formation cause has been approached briefly and some elimination or decrease measures have been given. So,the bases have been supplied for growth of higher quality and larger size sapphire crystals.
出处
《人工晶体学报》
EI
CAS
CSCD
北大核心
2000年第1期42-44,共3页
Journal of Synthetic Crystals
