First-Principles Assessment of the Structure and Stability of 15 Intrinsic Point Defects in Zinc-Blende Indium Arsenide

Qing Peng,Nanjun Chen,Eric Heller,David Cardimona,Fei Gao,Danhong Huang

doi:10.3390/cryst9010048

Qing Peng, Nanjun Chen + Show 4 more

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https://doi.org/10.3390/cryst9010048

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Abstract

Point defects are inevitable, at least due to thermodynamics, and essential for engineering semiconductors. Herein, we investigate the formation and electronic structures of fifteen different kinds of intrinsic point defects of zinc blende indium arsenide (zb-InAs ) using first-principles calculations. For As-rich environment, substitutional point defects are the primary intrinsic point defects in zb-InAs until the n-type doping region with Fermi level above 0.32 eV is reached, where the dominant intrinsic point defects are changed to In vacancies. For In-rich environment, In tetrahedral interstitial has the lowest formation energy till n-type doped region with Fermi level 0.24 eV where substitutional point defects In A s take over. The dumbbell interstitials prefer < 110 > configurations. For tetrahedral interstitials, In atoms prefer 4-As tetrahedral site for both As-rich and In-rich environments until the Fermi level goes above 0.26 eV in n-type doped region, where In atoms acquire the same formation energy at both tetrahedral sites and the same charge state. This implies a fast diffusion along the t − T − t path among the tetrahedral sites for In atoms. The In vacancies V I n decrease quickly and monotonically with increasing Fermi level and has a q = − 3 e charge state at the same time. The most popular vacancy-type defect is V I n in an As-rich environment, but switches to V A s in an In-rich environment at light p-doped region when Fermi level below 0.2 eV. This study sheds light on the relative stabilities of these intrinsic point defects, their concentrations and possible diffusions, which is expected useful in defect-engineering zb-InAs based semiconductors, as well as the material design for radiation-tolerant electronics.

Highlights

The III-V zinc-blende semiconductors are among the most important semiconductors, and have recently received much attention since they have potential to be employed as base materials for light-emitting diodes, infrared photodetectors, and spintronic devices, e.g., quantum-dot and quantum-well applications [1,2,3]
We primarily focus on the formation energy of various point defects, providing insights in understanding defect energetics within the bulk InAs crystal
Our study aims to provide an extensive and accurate study of the intrinsic point defect formation which is missed in the literature, e.g., a very recent computational study [26], but is highly desirable

Summary

Introduction

The III-V zinc-blende semiconductors are among the most important semiconductors, and have recently received much attention since they have potential to be employed as base materials for light-emitting diodes, infrared photodetectors, and spintronic devices, e.g., quantum-dot and quantum-well applications [1,2,3]. The III-V semiconductors are strong candidates to be incorporated into high-performance opto-electronics due to their direct band gap and high electron mobility [7,8]. In the family of III-V materials, InAs stands out because of its very high electron mobility which can be as much as three times higher than those in InGaAs and GaAs [7,9]. Crystals 2019, 9, 48 it acquires a small direct band gap of 0.35 eV at room temperature and a low carrier effective masses as well [10]. Together, these properties make InAs a promising candidate for incorporation into next-generation nano-electronics [7]. InAs has already been made successfully into nanowires [11,12,13] and demonstrated to integrate well into novel field-effect transistor (FET) device geometries [14,15,16,17]

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