开放体系优化ZnSe多晶原料化学计量比

Optimize Stoichiometric Ratio of ZnSe Polycrystalline Materials by Open System

本文采用开放体系对两单质加反应促进剂I2合成的ZnSe多晶原料进行了提纯。以高纯氩气为保护气体,提纯温度分别为500℃、550℃和800℃。能谱分析(EDS)和热重图谱(TG)结果表明:800℃处理后的ZnSe多晶原料,其化学计量比与理想化学计量比非常接近,而且升华开始温度提高到了850℃以上。运用化学气相输运(CVT)法进行晶体生长结果进一步表明,以800℃处理后的ZnSe多晶为原料时,消除了单质Se在生长区沉积对晶体成核生长的影响,达到了CVT法晶体生长对原料的要求。此外,以混合气体(H210%+Ar 90%)作为保护气时,在同等条件下处理后的ZnSe多晶原料,其化学计量比更加接近理想化学计量比,较氩气保护下的处理效果要好。

The ZnSe polycrystalline materials which were synthesized using Zn and Se as the raw matierials and the iodine as the transport agent were purified by open system.High purity argon gas as protective atmosphere,purified temperatures were 500 ℃,550 ℃ and 800 ℃,EDS and TGA results indicate that the stoichiometric ratio of ZnSe polycrystalline materials treated at 800 ℃ is very close to the ideal stoichiometric ratio,and the starting temperature of sublimation of polycrystalline materials is higher than 850 ℃.The results of crystal growth by chemical vapor transport（CVT） method showed that ZnSe polycrystalline materials treated at 800 ℃ eliminated Se deposition in the growth zone.After purification,the polycrystalline materials could satisfy the requirements of CVT method.In addition,mixed gas（H210%＋Ar 90%） as protective atmosphere,the stoichiometric ratio of ZnSe polycrystalline materials treated under the same conditions is closer to the ideal stoichiometric ratio,the results are better than that argon gas as protective atmosphere.