Modeling Fermi Level Effects in Atomistic Simulations

AbstractIn this work, variations in electron potential are incorporated into a Kinetic Lattice Monte Carlo (KLMC) simulator and applied to dopant diffusion in silicon. To account for the effect of dopants, the charge redistribution induced by an external point charge immersed in an electron (hole) sea is solved numerically using the quantum perturbation method. The local carrier concentrations are then determined by summing contributions from all ionized dopant atoms and charged point defects, from which the Fermi level of the system is derived by the Boltzmann equation. KLMC simulations with incorporated Fermi level effects are demonstrated for charged point defect concentration as a function of Fermi level, coupled diffusion phenomenon and field effect on doping fluctuations.

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Mechanisms of Doping-Enhanced Superlattice Disordering and of Gallium Self-Diffusion in GaAs

MRS Proceedings ◽

10.1557/proc-104-605 ◽

1987 ◽

Vol 104 ◽

Cited By ~ 1

Author(s):

T. Y. Tan ◽

U. Gösele ◽

B. P. R. Marioton

Keyword(s):

Fermi Level ◽

Point Defect ◽

Dopant Diffusion ◽

Self Diffusion ◽

N Doping ◽

Charged Point Defect ◽

Charged Point ◽

Defect Species ◽

Level Effect ◽

Positively Charged

ABSTRACTRecently available Ga-Al interdiffusion results in GaAs/AlAs superlattices allow to conclude that Ga self-diffusion in GaAs is carried by triply-negatively charged Ga vacancies under intrinsic and n-doping conditions. The mechanism of the Si enhanced superlattice disordering is the Fermi-level effect which increases the concentrations of the charged point defect species. For the effect of the p-dopants Be and Zn, the Fermi-level effect has to be considered together with dopant diffusion induced Ga self-interstitial supersaturation or undersaturation. Self-diffusion of Ga in GaAs under heavy p-doping conditions is governed by positively charged Ga self-interstitials.

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Lattice Monte-Carlo Simulations of Vacancy-Mediated Diffusion and Implications for Continuum Models of Coupled Diffusion

Simulation of Semiconductor Devices and Processes ◽

10.1007/978-3-7091-6619-2_115 ◽

1995 ◽

pp. 476-479 ◽

Cited By ~ 2

Author(s):

S. T. Dunham ◽

C. D. Wu

Keyword(s):

Monte Carlo ◽

Monte Carlo Simulations ◽

Continuum Models ◽

Lattice Monte Carlo ◽

Coupled Diffusion

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The chemical potential for a semiconductor

10.1093/oso/9780198857242.003.0026 ◽

2021 ◽

pp. 336-345

Author(s):

Geoffrey Brooker

Keyword(s):

Fermi Level ◽

Chemical Potential ◽

Electron Hole ◽

Densities Of States ◽

The Way

“The chemical potential for a semiconductor” deals with the way in which the chemical potential (Fermi level) of a semiconductor is affected: by the densities of states in the bands; by temperature; and by doping. The electron–hole product is usually independent of doping but sensitive to temperature. The chemical potential is worked out numerically for an example case, and is shown to be most sensitive to doping.

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Dynamic charge transfer through Fermi level equilibration in the p-CuFe2O4/n-NiAl LDH interface towards photocatalytic application

Catalysis Science & Technology ◽

10.1039/d0cy00980f ◽

2020 ◽

Vol 10 (18) ◽

pp. 6285-6298 ◽

Cited By ~ 1

Author(s):

Snehaprava Das ◽

Sulagna Patnaik ◽

Kulamani Parida

Keyword(s):

Photocatalytic Activity ◽

Charge Transfer ◽

Energy Level ◽

Fermi Level ◽

Vacuum Energy ◽

Electron Hole ◽

Photocatalytic Application ◽

Dynamic Charge ◽

Hole Recombination

The Ni Al LDH–CuFe2O4 p–n heterojunction, through vacuum energy level bending, inhibits electron hole recombination and enhances photocatalytic activity.

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Mobile Charged Point Defect Contribution to the Low Frequency Dielectric Response of LiNbO3belowTc

Japanese Journal of Applied Physics ◽

10.7567/jjaps.24s2.1025 ◽

1985 ◽

Vol 24 (S2) ◽

pp. 1025 ◽

Cited By ~ 4

Author(s):

C. Prieto ◽

L. Arizmendi ◽

J. A. Gonzalo

Keyword(s):

Point Defect ◽

Dielectric Response ◽

Low Frequency ◽

Charged Point Defect ◽

Charged Point

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Understanding ion beam synthesis of nanostructures: Modeling and atomistic simulations

MRS Proceedings ◽

10.1557/proc-647-o2.3 ◽

2000 ◽

Vol 647 ◽

Cited By ~ 4

Author(s):

M. Strobel ◽

K.-H. Heinig ◽

W. Möller

Keyword(s):

Ion Implantation ◽

Ion Beam ◽

Monte Carlo Model ◽

Atomistic Simulations ◽

Ion Energy ◽

Lattice Monte Carlo ◽

Supersaturated Solid Solutions ◽

Ion Beam Synthesis ◽

Thermodynamic Effects ◽

Low Dimensional

AbstractIon implantation, specified by parameters like ion energy, ion fluence, ion flux and sub-strate temperature, has become a well-established tool to synthesize buried low-dimensional nanostructures. In general, in ion beam synthesis the evolution of nanostructures is determined by the competition between ballistic and thermodynamic effects. A kinetic 3D lattice Monte-Carlo model is introduced, which allows for a proper incorporation of collisional mixing and phase separation within supersaturated solid-solutions. It is shown, that for both the ballistically and thermodynamically dominated regimes, the Gibbs-Thomson relation is the key ingredient in understanding nanocluster evolution. Various aspects of precipitate evolution during implantation, formation of ordered arrays of nanophase domains by focused ion implantation and compound nanocluster synthesis are discussed.

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Structure And Composition Of Grain Boundaries In SrTiO3

Microscopy and Microanalysis ◽

10.1017/s1431927600013799 ◽

1999 ◽

Vol 5 (S2) ◽

pp. 94-95

Author(s):

O. Kienzle ◽

F. Ernst ◽

Manfred Rühle

Keyword(s):

Grain Boundary ◽

Grain Boundaries ◽

Point Defects ◽

Coincidence Site Lattice ◽

Boundary Segregation ◽

Grain Boundary Segregation ◽

Boundary Structure ◽

Dopant Atoms ◽

Charged Point ◽

Atomistic Structure

The electrical properties of SrTiO3 (strontium titanate) ceramics are strongly influenced or even dictated by grain boundary segregation of charged point defects, such as dopant atoms, impurities, vacancies, or self-interstitials. The atomistic structure of the grain boundaries, their energy, and the segregation of point defects mutually depend on each other. Grain boundary segregation of charged point defects induces the formation of space charge layers in the adjoining crystals. In order to investigate the relation between grain boundary structure and composition, grain boundaries in Fedoped SrTiO3 bicrystals and in SrTiO3 ceramics were studied by HRTEM and by AEM with subnanometer resolution.Quantitative HRTEM served to investigate the atomistic structure of Σ=3, (111) grain boundaries in Fe-doped SrTiO3 bicrystals with a doping level of Fe/Ti= 0.04at% (Fig. 1). Analysis of the translation state revealed that the Σ=3, (111) grain boundary has an excess volume: normal to the boundary plane, the spacing between the two crystals exceeds what one would expect from a coincidence site lattice model by (0.06 ±0.01 )nm.

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