【摘要】 应用红外光谱、高分辨透射电镜研究了高碳CZ硅中的氧沉淀.实验表明:高碳样品中有两种成核长大机制形成的氧沉淀,一是多碳中心的异质成核长大的氧沉淀,碳原子同时参与氧沉淀的成核和长大,红外光谱上1230cm-1处无氧沉淀的特征峰,TEM观察这种氧沉淀是10~30nm高密度的球状小沉淀;另一种氧沉淀类似于低碳样品中均匀成核长大的氧沉淀,它在红外光谱上1230cm-1处有吸收峰,TEM观察这种氧沉淀是100~300nm各种形态的大沉淀.热处理条件不同可以改变两种机制相互竞争的优势,低于900℃的热处理以异质成核为主,而只有经过1200℃高温预处理破坏异质核心后,再在900℃以上热处理时,均匀成核长大的氧沉淀才会占优势.更多还原

【Abstract】 Oxygen precipitation in CZ silicon with high carb on concentration has been investigated by Fourier transform infrared spectroscopy (FTIR) and high resolution transmission electron microscopy(TEM).Experiment results show that there are two kinds nuclei of oxygen precipitates.One is the heterogeneous nucleus which is related to carbon-oxygen complexes.After the nucleation,carbon atoms simultaneously participate in the growth of oxygen precipitates.Because radius of carbon atoms is smaller,those oxygen precipitates exist small stress.And no FTIR peak at 1230cm -1 can be observed.According to TEM observation,those oxygen precipitates with high density are 10～30nm in size and spherical shape.Another is homogeneous nucleus which is related to the FTIR peak at 1230cm -1 .Those oxygen precipitates are bigger and 100～300nm in size.The formations of these two kinds of nuclei are dependent on annealing condition.If the annealing temperature is lower than 900℃,heterogeneous nucleation is main.After annealing at 1200℃ followed by annealing at above 900℃,homogeneous nucleation dominates.更多还原