论文标题
IV组六角形甲状腺型晶体中的外部掺杂
Extrinsic doping in group IV hexagonal-diamond type crystals
论文作者
论文摘要
在过去的几年中，由于新颖且非常有效的生长方法的出现，IV组六角形甲状腺型晶体在半导体物理学中引起了极大的关注。但是，许多问题在其外部掺杂能力以及与钻石状结构的外部掺杂能力以及其比较方面保持不足。此点通过在密度功能理论（DFT）的框架中进行的数值模拟进行了研究。 The comparative analysis for group III and V dopant atoms shows that: i) in diamond-type crystals the bulk sites symmetry ($T_d$) is preserved by doping while in hexagonal crystals the impurity site moves towards a higher ($T_d$) or lower ($C_{3v}$) symmetry configuration dependently on the valence of the dopant atoms; ii）对于SI和GE，可以更容易地在六角形钻石阶段引入III组杂质，其本地$ C_ {3V} $对称可以更好地适应杂质的三倍协调，而N型杂质则没有显示出任何明显的相位偏好； iii）对于C，N和P掺杂剂在六边形辅助结构中都比立方体更稳定，但是对于N型杂质而言，这种趋势更为明显。
Over the last few years, group IV hexagonal-diamond type crystals have acquired great attention in semiconductor physics thanks to the appearance of novel and very effective growth methods. However, many questions remain unaddressed on their extrinsic doping capability and on how it compares to those of diamond-like structures. This point is here investigated through numerical simulations conducted in the framework of the Density Functional Theory (DFT). The comparative analysis for group III and V dopant atoms shows that: i) in diamond-type crystals the bulk sites symmetry ($T_d$) is preserved by doping while in hexagonal crystals the impurity site moves towards a higher ($T_d$) or lower ($C_{3v}$) symmetry configuration dependently on the valence of the dopant atoms; ii) for Si and Ge, group III impurities can be more easily introduced in the hexagonal-diamond phase, whose local $C_{3v}$ symmetry better accommodates the three-fold coordination of the impurity, while n-type impurities do not reveal any marked phase preference; iii) for C, both n and p dopants are more stable in the hexagonal-diamond structure than in the the cubic one, but this tendency is much more pronounced for n-type impurities.
