Arsenic doping and diffusion in CdTe: a DFT study of bulk and grain boundaries.
Arsenic doping and diffusion in CdTe: a DFT study of bulk and grain boundaries.
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CdTe 中的砷掺杂和扩散：块体和晶界的 DFT 研究。
DOI：
10.1088/1361-648x/aca8e5
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发表时间：
2022
期刊：
影响因子：
--
通讯作者：
Hatton P
中科院分区：
文献类型：
--
作者：
Hatton P
用As掺杂CdTe被认为是通过增加电子空穴浓度来增加电池效率的方法。这种掺杂依赖于As通过CdTe的扩散，导致As Te取代。这被认为是通过动力学和电子性质的计算，在散装和1003和1009晶界使用密度泛函理论的潜在有效性。在块状锌-碲化镉中，孤立的砷以< 0.5 eV的势垒扩散，并以类似的势垒通过纤锌矿结构的碲化镉，由堆垛层错产生，这表明砷将不会被捕获在堆垛层错处，因此孤立的砷的传输将在块状碲化镉中不受阻碍。取代砷在体碲化镉的带隙上的影响很小，除了当它是正电荷的AX-中心位置或发生作为一个双间隙。然而，与氯的情况相反，存在于晶界中的砷将缺陷态引入到带隙中。这表明，在引入单个砷原子之前，首先用氯饱和晶界的掺杂策略可能更有益。
The doping of CdTe with As is a method which is thought to increase cell efficiency by increasing electron hole concentrations. This doping relies on the diffusion of As through CdTe resulting in As Te substitution. The potential effectiveness of this is considered through kinetic and electronic properties calculations in both bulk and Σ3 and Σ9 grain boundaries using Density Functional Theory. In bulk zinc-blende CdTe, isolated As diffuses with barriers< 0.5 eV and with similar barriers through wurtzite structured CdTe, generated by stacking faults, suggesting that As will not be trapped at the stacking faults and hence the transport of isolated As will be unhindered in bulk CdTe. Substitutional arsenic in bulk CdTe has little effect on the band gap except when it is positively charged in the AX-centre position or occurring as a di-interstitial. However in contrast to the case of chlorine, arsenic present in the grain boundaries introduces defect states into the band gap. This suggests that a doping strategy whereby the grain boundaries are first saturated with chlorine, before single arsenic atoms are introduced, might be more beneficial.