A review of defects and disorder in multinary tetrahedrally bonded semiconductors. (10th November 2016)

• Record Type: Journal Article
• Authors: Baranowski, Lauryn L; Zawadzki, Pawel; Lany, Stephan; Toberer, Eric S; Zakutayev, Andriy
• Is Part Of: Semiconductor science and technology. Volume 31:Number 12(2016:Dec.)
• Publication Date: 2016-11-10
• Subjects: thin film deposition -- density functional theory -- Earth abundant materials -- next generation photovoltaics -- compound semiconductors -- point defects -- cation site disorder; Semiconductors -- Periodicals; 621.38152
• DOI: 10.1088/0268-1242/31/12/123004
• Languages: English
• ISSNs: 0268-1242

Abstract

Abstract: Defects are critical to understanding the electronic properties of semiconducting compounds, for applications such as light-emitting diodes, transistors, photovoltaics, and thermoelectrics. In this review, we describe our work investigating defects in tetrahedrally bonded, multinary semiconductors, and discuss the place of our research within the context of publications by other groups. We applied experimental and theory techniques to understand point defects, structural disorder, and extended antisite defects in one semiconductor of interest for photovoltaic applications, Cu2 SnS3 . We contrast our findings on Cu2 SnS3 with other chemically related Cu–Sn–S compounds, as well as structurally related compounds such as Cu2 ZnSnS4 and Cu(In, Ga)Se2 . We find that evaluation of point defects alone is not sufficient to understand defect behavior in multinary tetrahedrally bonded semiconductors. In the case of Cu2 SnS3 and Cu2 ZnSnS4, structural disorder and entropy-driven cation clustering can result in nanoscale compositional inhomogeneities which detrimentally impact the electronic transport. Therefore, it is not sufficient to assess only the point defect behavior of new multinary tetrahedrally bonded compounds; effects such as structural disorder and extended antisite defects must also be considered. Overall, this review provides a framework for evaluating tetrahedrally bonded semiconducting compounds with respect to their defect behavior for photovoltaic and other applications, and suggests new materials that may not be as prone to such imperfections.