摘要
室温下使用维氏硬度计研究了硅单晶表面的接触损伤及硅单晶中杂质对表面损伤的影响 .实验发现 ,硅单晶的硬度不仅与晶体的本身特性——晶向有关 ,还与所掺入杂质的种类和浓度有关 .损伤造成的裂纹倾向于沿着〈1 1 0〉晶向扩展 ,而且 { 1 1 1 }面上的硬度要大于 { 1 0 0 }面 .重掺 n型单晶由于能带结构的变化而使硬度下降 ;相反 ,重掺
The contact damage and fracture property of silicon single crystal are investigated at room temperature by indentation,as well as the influence of the intended and unintended impurities.It is found that the contact damage is related with the crystal lattice orientation anisotropy and doped impurities.The damage fracture propagats preferentially on the 〈110〉 orientation.Also due to the pinning effect of atoms on dislocations,the doped nitrogen increases the hardness as well as the heavy doped boron atoms.On the contrary,the heavy doped antimony atoms will decrease the hardness,which may be caused by the change of band structure.From this viewpoint,the doped impurities can not only change the electric and optical characteristics,but also influence the mechanical property of silicon single crystal.
基金
国家自然科学基金 (批准号 :5 0 0 3 2 0 10 )
教育部留学回国人员基金
国家高技术研究发展计划 ( No.2 0 0 2 AA3 Z1111)资助项目~~
