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Title: Re-examining the silicon self-interstitial charge states and defect levels: A density functional theory and bounds analysis study

Journal Article · · AIP Advances
DOI: https://doi.org/10.1063/5.0016134 · OSTI ID:1670753

The self-interstitial atom (SIA) is one of two fundamental point defects in bulk Si. Isolated Si SIAs are extremely difficult to observe experimentally. Even at very low temperatures, they anneal before typical experiments can be performed. Given the challenges associated with experimental characterization, accurate theoretical calculations provide valuable information necessary to elucidate the properties of these defects. Previous studies have applied Kohn–Sham density functional theory (DFT) to the Si SIA, using either the local density approximation or the generalized gradient approximation to the exchange-correlation (XC) energy. The consensus of these studies indicates that a Si SIA may exist in five charge states ranging from -2 to +2 with the defect structure being dependent on the charge state. This study aims to re-examine the existence of these charge states in light of recently derived “approximate bounds” on the defect levels obtained from finite-size supercell calculations and new DFT calculations using both semi-local and hybrid XC approximations. We conclude that only the neutral and +2 charge states are directly supported by DFT as localized charge states of the Si SIA. Within the current accuracy of DFT, our results indicate that the +1 charge state likely consists of an electron in a conduction-band-like state that is coulombically bound to a +2 SIA. Furthermore, the -1 and -2 charge states likely consist of a neutral SIA with one and two additional electrons in the conduction band, respectively.

Research Organization:
Sandia National Laboratories (SNL-NM), Albuquerque, NM (United States)
Sponsoring Organization:
USDOE Office of Science (SC), Basic Energy Sciences (BES) (SC-22)
Grant/Contract Number:
AC04-94AL85000
OSTI ID:
1670753
Alternate ID(s):
OSTI ID: 1657268
Report Number(s):
SAND2020--8149J; {689789,"Journal ID: ISSN 2158-3226"}
Journal Information:
AIP Advances, Journal Name: AIP Advances Journal Issue: 9 Vol. 10; ISSN 2158-3226
Publisher:
American Institute of Physics (AIP)Copyright Statement
Country of Publication:
United States
Language:
English

References (49)

Molecular dynamics study of the configurational and energetic properties of the silicon self-interstitial journal February 2005
Barrier to Migration of the Silicon Self-Interstitial journal March 1984
Microscopic theory of atomic diffusion mechanisms in silicon journal December 1984
Special points for Brillouin-zone integrations journal June 1976
Efficient iterative schemes for ab initio total-energy calculations using a plane-wave basis set journal October 1996
Electronic structure and total-energy migration barriers of silicon self-interstitials journal August 1984
Electronic structure modeling of InAs/GaSb superlattices with hybrid density functional theory journal March 2017
Theory of Defect Levels and the “Band Gap Problem” in Silicon journal June 2006
Model of defect reactions and the influence of clustering in pulse-neutron-irradiated Si journal August 2008
Ab initio pseudopotentials for electronic structure calculations of poly-atomic systems using density-functional theory journal June 1999
Generalized Gradient Approximation Made Simple journal October 1996
Periodic boundary conditions in ab initio calculations journal February 1995
First-principles study of the self-interstitial diffusion mechanism in silicon journal February 1998
Point Defect Charge‐State Effects on Transient Diffusion of Dopants in Si journal January 1990
Interstitial hydrogen and neutralization of shallow-donor impurities in single-crystal silicon journal February 1986
Review—Properties of Intrinsic Point Defects in Si and Ge Assessed by Density Functional Theory journal January 2016
Perspective: Treating electron over-delocalization with the DFT+U method journal June 2015
Simple intrinsic defects in gallium arsenide journal November 2009
First-principles determination of defect energy levels through hybrid density functionals and GW journal March 2015
Diffusion and carrier recombination by interstitials in silicon journal April 1998
Effects of carbon on the electrical and optical properties of InN, GaN, and AlN journal January 2014
Formation energies, binding energies, structure, and electronic transitions of Si divacancies studied by density functional calculations journal November 2006
Density-functional-theory calculations for the silicon vacancy journal October 2006
Bounds on the range of density-functional-theory point-defect levels in semiconductors and insulators journal September 2014
Ab initio pseudopotential calculations of dopant diffusion in Si journal November 1998
Localization and Delocalization Errors in Density Functional Theory and Implications for Band-Gap Prediction journal April 2008
Self-Consistent Equations Including Exchange and Correlation Effects journal November 1965
The nature of the charged-self-interstitial in silicon journal November 1987
Role of nitrogen vacancies in the luminescence of Mg-doped GaN journal April 2012
Self-Diffusion in Silicon: Similarity between the Properties of Native Point Defects journal October 1999
First-principles calculations of self-diffusion constants in silicon journal April 1993
First-principles calculation of intrinsic defect formation volumes in silicon journal November 2005
Rationale for mixing exact exchange with density functional approximations journal December 1996
Physical atomistic kinetic Monte Carlo modeling of Fermi-level effects of species diffusing in silicon journal July 2005
A new mechanism for interstistitial migration journal January 1972
Application of the bounds-analysis approach to arsenic and gallium antisite defects in gallium arsenide journal January 2015
New Perspective on Formation Energies and Energy Levels of Point Defects in Nonmetals journal February 2012
Interstitial charge states in boron-implanted silicon journal March 2005
Self-consistent hybrid functional for condensed systems journal May 2014
Generalized norm-conserving pseudopotentials journal August 1989
From ultrasoft pseudopotentials to the projector augmented-wave method journal January 1999
Nonparametrized tight-binding method for local and extended defects in homopolar semiconductors journal September 1991
Fractional charge perspective on the band gap in density-functional theory journal March 2008
Nature and diffusion of the self-interstitial in silicon journal June 1983
Effects of d-electrons in pseudopotential screened-exchange density functional calculations journal June 2008
Projector augmented-wave method journal December 1994
First-principles calculations of self-interstitial defect structures and diffusion paths in silicon journal December 1999
Calculations of Silicon Self-Interstitial Defects journal September 1999
Electrostatics-based finite-size corrections for first-principles point defect calculations journal May 2014