Vacancy and Doping States in Monolayer and bulk Black Phosphorus.
Vacancy and Doping States in Monolayer and bulk Black Phosphorus.
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DOI：
10.1038/srep14165
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发表时间：
2015-09-18
影响因子：
4.6
通讯作者：
Robertson J
中科院分区：
文献类型：
--
作者：
Guo Y;Robertson J
计算了少层黑磷和块体黑磷中点缺陷和替位掺杂的原子几何构型和跃迁能级。发现空位在单层P中重构以留下单个悬挂键，从而在价带边缘以上0.24 eV处产生具有+/-跃迁能级的负U缺陷。V−态形成了一个不寻常的4重配位位点。在少层和块状黑P中，缺陷变成正U位点。双空位比单空位稳定得多，并且它可以重构而不产生深能隙态。替代掺杂剂如C、Si、O或S不会产生浅施主或受主态，而是重建以形成类似于GaAs中的DX或AX中心的非掺杂位点。黑色P上的杂质采用8-N规则成键，就像在非晶半导体中一样，而不是在四面体半导体中看到的简单替代几何形状。
The atomic geometries and transition levels of point defects and substitutional dopants in few-layer and bulk black phosphorus are calculated. The vacancy is found to reconstruct in monolayer P to leave a single dangling bond, giving a negative U defect with a +/− transition level at 0.24 eV above the valence band edge. The V− state forms an unusual 4-fold coordinated site. In few-layer and bulk black P, the defect becomes a positive U site. The divacancy is much more stable than the monovacancy, and it reconstructs to give no deep gap states. Substitutional dopants such as C, Si, O or S do not give rise to shallow donor or acceptor states but instead reconstruct to form non-doping sites analogous to DX or AX centers in GaAs. Impurities on black P adopt the 8-N rule of bonding, as in amorphous semiconductors, rather than simple substitutional geometries seen in tetrahedral semiconductors.