低能离子束方法制备重掺杂Fe的Si∶Fe固溶体

Si∶Fe Solid Solution Heavily Doped with Fe Prepared by Technique of Low Energy Ion Beam

利用质量分离的低能离子束方法 ,以离子能量为 1 0 0 0 e V,剂量为 3× 1 0 1 7cm- 2 ,室温下往 p型 Si(1 1 1 )单晶衬底注入 Fe离子 ,注入的样品在 4 0 0℃真空下进行热处理 .俄歇电子能谱法 (AES)对原位注入样品深度分析表明 Fe离子浅注入到 p型 Si单晶衬底 ,注入深度约为 4 2 nm.X射线衍射法 (XRD)对热处理样品结构分析发现只有 Si衬底的衍射峰 ,没有其他新相 .X射线光电子能谱法 (XPS)对热处理样品表面分析发现 Fe2 p束缚能对应于单质 Fe的峰 ,没有形成 Fe的硅化物 .这些结果表明重掺杂 Fe的 Si∶ Fe固溶体被制备 .电化学 C- V法测量了热处理后样品载流子浓度随深度的分布 ,发现 Fe重掺杂 Si致使 Si的导电类型从 p型转为 n型 ,Si∶ Fe固溶体和 Si衬底形成 pn结 。

Fe irons are implanted into p type Si (111) single crystal by low energy ion beam technique at room temperature with energy of 1000eV and a dose of 3×10 17 cm 2 . Subsequent annealing is performed at 400℃ under the vacuum condition. Auger electron spectroscopy depth profile of the as implanted sample indicates that the iron ions are shallowly implanted into the p type silicon single crystal substrate and the implantation depth is 42nm. X ray diffraction measurement shows that there are no other diffraction peaks besides silicon substrate peak in the annealed sample. X ray photoelectron spectra show that the iron 2p peak of binding energy corresponds to pure iron and suggest that no iron silicide is formed in the annealed sample. All of these results indicate that Si∶Fe solid solution heavily doped with Fe is prepared.Electrochemical C V carrier concentration depth profile indicates that silicon conduction type transfers from p type into n type by heavily doping with iron.A p n junction is formed between Si∶Fe solid solution and silicon substrate and shows rectifying behaviour.