硅中三空位V_3^-的超精细相互作用的理论计算

THEORETICAL CALCULATIONS OF HYPERFINE INTERACTIONS OF TRIVACANCY IN SILICON

利用Koster-Slater的格林函数方法,计算了硅中三空位v_3^- 的电子态能级和波函数.结果表明,v_X^-在禁带中有五条能级:E_A_2=0.417eV,E_B_1=0.492eV,E凡一0·512ev,民一O.532eV,EB_2~2=0.608eV.根据算得的超精细相互作用常数同实验值的比较,定出v_3^-处于B_1态.V_3^-的B_1态点据第1壳层的几率为60.2％,但主要集中在三空位所确定的平面内的二个原子上.

The deep energy levels and the wavefunctions of V3- in silicon are calculated by using the Koster-Slater Green's function method. Numerical results show that there are five energy levels in the energy gap, i.e., EA2 = 0.417eV, EB1 = 0.492eV, EB21= 0.512eV, EA1 - 0.532eV and EB22= 0.608eV. The hyperfine interactions (h.f.) constant associated with these states are calculated. According to the comparison of the theoretical h.f. constant with the experiments, we determine that the B1-state is occupied by the unpaired electron of V3-. The distributed probability of V3- in B1-state on the nearest neighbour atoms is about 60.2%, the major part of which is centered on the two atoms in the plane determined by the trivacancy.