Foundations of ab initio simulations of electric charges and fields at semiconductor surfaces within slab models

Abstract

Semiconductor surfaces were divided into charge categories, i.e. surface acceptor, donor and neutral ones that are suitable for simulations of their properties within a slab model. The potential profiles, close to the charged surface states, accounting for explicit dependence of the point defects energy, were obtained. A termination charge slab model was formulated and analyzed proving that two control parameters of slab simulations exist: the slope and curvature of electric potential profiles which can be translated into a surface and volumetric charge density. The procedures of slab model parameter control are described and presented using examples of the DFT simulations of GaN and SiC surfaces showing the potential profiles, linear or curved, depending on the band charge within the slab. It was also demonstrated that the field at the surface may affect some surface properties in a considerable degree proving that verification of this dependence is obligatory for a precise simulation of the properties of semiconductor surfaces.

37 pages, 11 figures

References in corpus (3)

• Fermi level influence on the adsorption at semiconductor surfaces - ab initio simulations
• On the nature of Surface States Stark Effect at clean GaN(0001) surface
• Energy of adsorption at semiconducting surfaces with Fermi level differently pinned -- ab initio study

Cited by in corpus (8)

• A multi-scale approach to the electronic structure of doped semiconductor surfaces
• Adsorption of ammonia at GaN(0001) surface in the mixed ammonia/hydrogen ambient - a summary of ab initio data
• Charged surfaces and slabs in periodic boundary conditions
• General aspects of the vapor growth of semiconductor crystals - a study based on DFT simulations of the NH3/NH2 covered GaN(0001) surface in hydrogen ambient
• Polarization doping ab initio verification of the concept charge conservation and nonlocality
• Electrostatic treatment of charged interfaces in classical atomistic simulations
• Surface charge induced $s{p}^3$-$s{p}^2$ transformation: new energy optimization universal mechanism of (4x4) reconstruction of stoichiometric GaN(0001) surface
• Fundamentals of the metal contact to p-type GaN: new multilayer design