α－Si_3N_4晶须中缺陷与晶须生长气氛关系的研究  

RELATIONSHIP BETWEEN THE DEFECTS OF ALPHA-SILICON NITRIDE WHISKERS AND GROWTH ATMOSPHERE

作　　者：吴华武[1] 徐功骅[1] 尉京志[1] 来月英[1] 张克宏[1] 

机构地区：[1]清华大学化学系

出　　处：《复合材料学报》1996年第2期60-64,共5页Acta Materiae Compositae Sinica

基　　金：国家自然科学基金

摘　　要：本文研究了用无定形氮化硅超细粉原位生长α－Ｓｉ３Ｎ４晶须，晶须生长温度为１４００～１４５０℃，恒温１～４ｈ。讨论了在晶须生长过程中，不同的保护气氛对晶须质量的影响。当晶须在高纯Ｎ２气氛中生长时，得到的晶须中氮含量为３２％～３４％，氧含量为８％～６％，氯含量为０．１％左右。这类晶须中存在着大量的缺陷。当晶须在ＮＨ３气氛中生长时，得到的晶须中氮含量为３９％左右，氧含量为１％，氯含量为０．０１％，在这类晶须的透射电镜照片中几乎看不到缺陷。Alpha-silicon nitride whiskers were prepared by the 'in-situ' growth of ultrafine amorphous silicon nitride powders.The experiment was carried out at 1400～1450℃ for 1～4 hours.When the experiment was conducted in the atmosphere of nitrogen with high purity,the nitrogen content,oxygen content and chlorine content in alpha-silicon nitride whiskers obtained were 32%～34%,8%～6% and～0.1%,respectively.A lot of defects were detected in the whisker.However,when the experiment was completed in an atmosphere of ammonia,the content of nitrogen,oxygen and chlorine in the whiskers changed to 39%,1% and 0.01%,respectively,where nearly' defect-free 'in the whisker was detected.

关 键 词：晶须 氮化硅 生长气氛 晶体缺陷 

分 类 号：O781[理学—晶体学]