【摘要】 本文在紧束缚近似下,利用Koster-Slater格林函数方法,研究了硅中代位式三原子集团D₃⁰（S₃⁰,Se₃⁰,Te₃⁰）和四原子集团D₄⁰（S₄⁰,Se₄⁰,Te₄⁰）的电子结构。给出了D₃⁰和三种不同对称位形(C_3e,C_2h和C₁)下D₄⁰杂质能级计算结果。还预言了一些杂质态在缺陷集团处的波函数。随着杂质中心上原子数目的增加,施主束缚能变浅。看来,实验观测到的与硫族中心有关的待定施主能级不是非最近邻原子构成的集团所产生的。更多还原

【Abstract】 The electronic structures of the substituional chalcogen-related centersfor three-atom clusters D₃⁰ and four-atom clusters D₄⁰ （D = S, Se, Te） in Siare investigated by using the Koster-Slater Green’s function method in anempirical tight binding approximation. The calculation results of the impuritylevels for D₃⁰ and D₄⁰ with three different symmetry configurations （C₃., C₂,and C₁） are presented. The wave functions on the defect clusters correspondingto some levels are predicted. A chalcogen impurity center would have shallowerdonor binding energy with the increase of the atoms included in it. It appearsthat the impurity clusters consisting of some non-nearest neighbor atoms arenot responsible for the experimentally observed donor levels of any chalcogencenters to be identified.更多还原