【摘要】 利用红外吸收、x射线形貌照相、x射线反常透射、俄歇电子能谱和高压透射电子显微镜研究了在450℃、700℃和1050℃热处理后无位错CZ-Si单晶中的氧、碳沉淀.从X射线反常透射强度的结果,证明甚至在较低温度 450℃热处理,沉淀即已产生.由红外吸收可以证明,在700℃热处理已有大量沉淀产生.但是由于沉淀颗粒太小,无法用X射线形貌相观察这种沉淀.沉淀物的大小估计为数埃至500埃.氧沉淀决定于氧含量和单晶的热历史.但是,碳和低高温两步热处理都可以促进氧沉淀.测定了700℃和1050℃经不同时间热处理所产生的氧、碳沉淀率.对于碳对氧沉淀的作用,沉淀图样和机理进行了讨论.更多还原

【Abstract】 Precipitation of oxygen and carbon in buk dislocation-free CZ Si annealed at450℃, 700℃ and 1050℃ has been studied using infrared absorption,X-ray topography,X-ray anomalous transmission,AES and HVTEM.The results of X-ray anomaloustransmission intensity show that the precipitation occurs even at the relatively low tem-perature of 450℃.IR absorption measurements show that a large amount of precipi-tation occurs at 700℃.Since the precipitated sze estimated to be a few angstrons to500A is too small,this precipitation can not be observed by X-ray topography.Theoxygen content and thermal history of the CZ-grown Si are both essential and sub-stantial factors for oxygen precipitation in Sj.However,carbon and two-step anneal-ing can promote the precipitation of oxygen.The precipitation rates of oxygen andcarbon after the heat treatments at 700℃ and 1050℃ over a wide range of time havebeen measured.The effect of carbon on the oxygen precipitation, precipitation patternand mechanism have also been discussed.更多还原