Surface relaxation effects on the properties of porous silicon

Autor:	E. Vázquez, Chumin Wang, Julia Tagüeña-Martínez, L. E. Sansores
Rok vydání:	2002
Předmět:	Materials science Condensed matter physics Silicon Band gap General Physics and Astronomy chemistry.chemical_element Porous silicon Pseudopotential Lattice constant Effective mass (solid-state physics) chemistry Computational chemistry Density functional theory Physics::Atomic Physics Porosity
Zdroj:	Journal of Applied Physics. 91:3085-3089
ISSN:	1089-7550 0021-8979
DOI:	10.1063/1.1446658
Popis:	In this article, surface relaxation and its effects on the electronic and structural properties of porous silicon are studied by using the total-energy pseudopotential formalism within the density-functional theory. Our model is based on a 32-atom supercell, where columns of atoms are removed and saturated with hydrogen atoms. Samples with 4.4%, 13.6%, 16.8%, 28.9%, and 41.3% porosity are analyzed in detail. The results show a clear expansion of the system along the pore direction as the porosity increases. Moreover, this expansion is very sensitive to the hydrogen-atom concentration and a linear dependence is observed. The dependence of the band gap and the effective mass on the porosity are also analyzed. Here, the hydrogen-atom number and pore shapes are observed to play a fundamental role.
Databáze:	OpenAIRE
Externí odkaz:	https://explore.openaire.eu/search/publication?articleId=doi_________::6938a6b3afe4031e7f63eec1a2da85c3 https://doi.org/10.1063/1.1446658 Zobrazit plný text záznamu