Search Menu
DOE PAGES title logo U.S. Department of Energy
Office of Scientific and Technical Information
Search Scholarly Publications

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
 [1];  [1]; ORCiD logo [1]
  1. Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)
+ Show Author Affiliations

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 Lab. (SNL-NM), Albuquerque, NM (United States)
Sponsoring Organization:
USDOE Office of Science (SC), Basic Energy Sciences (BES)
Grant/Contract Number:
AC04-94AL85000; NA0003525
OSTI ID:
1670753
Alternate ID(s):
OSTI ID: 1657268
Report Number(s):
SAND2020-8149J; 689789; TRN: US2204197
Journal Information:
AIP Advances, Vol. 10, Issue 9; ISSN 2158-3226
Publisher:
American Institute of Physics (AIP)Copyright Statement
Country of Publication:
United States
Language:
English

References (27)

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
Barrier to Migration of the Silicon Self-Interstitial journal March 1984
Electronic structure modeling of InAs/GaSb superlattices with hybrid density functional theory journal March 2017
Perspective: Treating electron over-delocalization with the DFT+U method journal June 2015
Formation energies, binding energies, structure, and electronic transitions of Si divacancies studied by density functional calculations journal November 2006
Calculations of Silicon Self-Interstitial Defects journal September 1999
Interstitial charge states in boron-implanted silicon journal March 2005
First-principles determination of defect energy levels through hybrid density functionals and GW journal March 2015
Role of nitrogen vacancies in the luminescence of Mg-doped GaN journal April 2012
Physical atomistic kinetic Monte Carlo modeling of Fermi-level effects of species diffusing in silicon journal July 2005
Model of defect reactions and the influence of clustering in pulse-neutron-irradiated Si journal August 2008
The nature of the charged-self-interstitial in silicon journal November 1987
A new mechanism for interstistitial migration journal January 1972
Nature and diffusion of the self-interstitial in silicon journal June 1983
Diffusion and carrier recombination by interstitials in silicon journal April 1998
Molecular dynamics study of the configurational and energetic properties of the silicon self-interstitial journal February 2005
Simple intrinsic defects in gallium arsenide journal November 2009
First-principles calculations of self-interstitial defect structures and diffusion paths in silicon journal December 1999
Ab initio pseudopotential calculations of dopant diffusion in Si journal November 1998
Effects of d-electrons in pseudopotential screened-exchange density functional calculations journal June 2008
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
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
Bounds on the range of density-functional-theory point-defect levels in semiconductors and insulators journal September 2014
Rationale for mixing exact exchange with density functional approximations journal December 1996

Figures / Tables (4)

FIG. 1(p. 3)figure FIG. 1
FIG. 2(p. 4)figure FIG. 2
TABLE I(p. 5)table TABLE I
FIG. 3(p. 6)figure FIG. 3

Similar Records

Related Subjects

36 MATERIALS SCIENCE