The influence of Ca doping in Bi2O2Se: A first-principles investigation

• Published in: Computational materials science Vol. 179; p. 109684
• Main Authors: Zhang, Xuyang, Han, Nannan, Lin, Changqing, Wei, Qilin, Zhao, Puqin, Cheng, Yingchun, Huang, Wei
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 15-06-2020
• Subjects: Bismuth oxychalcogenides; Doping; First-principles calculation; Point defects; First-principles calculation; Point defects; Bismuth oxychalcogenides; Doping
• ISSN: 0927-0256; 1879-0801
• DOI: 10.1016/j.commatsci.2020.109684

First-principles calculations are performed to investigated the influence of Ca doping on Bi2O2Se. The synthesis conditions and electronic structures of Ca-doped Bi2O2Se crystal are calculated. Ca-doped Bi2O2Se has potential application for optoelectronic devices.
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•Influence of Ca doping on Bi2O2Se is studied by using first-principles calculations.•Ca is easy to substitute Bi atom in Bi2O2Se and induces n-type conductivity.•Ca doping introduces a deep donor level within band gap of Bi2O2Se.•Ca doping widens the band gap of Bi2O2Se.
Bi2O2Se, as a member of bismuth oxychalcogenides, is regarded as a promising candidate for optoelectronic applications, such as phototransistors, photodetectors, pulsed lasers and photodiodes. Throughout the research progress of Bi2O2Se, the crystal quality of Bi2O2Se plays an important role. Using the first-principles calculations, we study the influence of Ca, one of the most abundant elements on the earth, doping in Bi2O2Se. We find that Ca doping is easy in Bi2O2Se which further induces substitution point defect CaBi. The presence of CaBi introduces a deep donor level which is favorable for a short carrier lifetime. Thus, Ca doping may be used to improve switching characteristics of Bi2O2Se-based diodes and transistors.