Electronic Materials Letters ( IF 2.4 ) Pub Date : 2020-08-01 , DOI: 10.1007/s13391-020-00238-9 Chengru Wang , Han Wu , Hong Zhu , Chaoying Xie
Abstract
Indium phosphide (InP) is one of the most important optoelectronic materials, while stacking faults (SFs), as planar defects, are usually inevitable during the growth of InP possibly due to the low SF energy. As n-type dopants, sulfur atoms are generally used to change the electron concentration of InP-based devices, whereas the effects of sulfur doping on SFs of InP have not been studied in detail. In this work, the generalized stacking fault (GSF) energies of pure and sulfur-doped InP have been investigated by gliding the layers successively in the framework of first principle calculations. The results reveal the stable SF energies of InP are low and extrinsic stacking fault could be seen as the twin embryos in pure InP. Sulfur doping could decrease the GSF energies dramatically due to the lower charge density along In-S bonds than along In-P bonds, which consequently enhances the ability of twinning locally. The preferential segregation of sulfur atoms on SFs or twin boundaries could further promote the thickening of microtwin in InP. These results are of great significance to the understanding of the formation of planar defects in n-type doped III–V compounds.
Graphic Abstract
中文翻译:
硫掺杂对磷化铟广义堆垛层错能的影响
摘要
磷化铟(InP)是最重要的光电材料之一,而在InP的生长过程中通常会不可避免地出现堆叠缺陷(SFs)作为平面缺陷,这可能是由于SF能量低所致。作为n型掺杂剂,通常使用硫原子来改变InP基器件的电子浓度,而尚未详细研究硫掺杂对InP SF的影响。在这项工作中,通过在第一原理计算的框架中连续滑动层,研究了纯的和掺杂硫的InP的广义堆叠故障(GSF)能量。结果表明,InP的稳定SF能量低,外在堆垛层错可以看作是纯InP的双胎。由于沿In-S键的电荷密度低于沿In-P键的电荷密度,硫掺杂可显着降低GSF能量,因此增强了局部孪晶的能力。SFs或双晶界上硫原子的优先偏析可进一步促进InP中微孪晶的增厚。这些结果对理解n型掺杂III–V化合物中平面缺陷的形成具有重要意义。