Regular Article

DFT calculations on the structural and electronic properties of vacancy effects in the silicon nanowires^★

¹ Departamento de Ciências Naturais, Universidade Federal de São João Del-Rei, Praça Dom Helvécio, 74, Fábricas, São João Del-Rei, MG 36301-160, Brazil
² Departmento de Física, Instituto de Ciências Exatas, Campus Universitário, Universidade Federal de Juiz de Fora, MG 36036-900, Brazil

^a e-mail: anaclaudia@ufsj.edu.br

Received: 26 September 2018
Received in final form: 23 January 2019
Published online: 1 April 2019

Abstract

A theoretical study was undertaken of the effects of single and multiple vacancies created at different surface sites of a non-passivated silicon nanowire (SiNW) with diameter ~11.0 Å, grown in the [001] direction. The results showed that vacancies at vertex site were most energetically favorable, due to the surface dimerization process, which was responsible for metallic or semi-metallic behavior in the perfect [001] SiNW. Modifications at wavefunction localization due surface dimerization and their consequences at electronic properties were also investigated and provided helpful information on application of these materials as gas-sensing nanodevices.