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Indexed by:Journal Papers

Date of Publication:2015-05-01

Journal:MATERIALS RESEARCH INNOVATIONS

Included Journals:SCIE、EI、Scopus

Volume:19

Page Number:S283-S286

ISSN No.:1432-8917

Key Words:Ab initio calculations; Boron; Oxygen; Bonding state

Abstract:Boron and oxygen are major non-metallic impurities in silicon, and they often exist in the form of boron and oxygen (B-O) pair, which plays an important role in silicon and can induce the silicon-based solar cell suffering a light-induced-degradation in efficiency up to 1-2%. In this work, the ab initio calculations based on the density functional theory (DFT) are carried out to understand the effect of silicon environment on B-O bonding state by comparing the states in vacuum, oxide, and silicon. It has been found out that the contribution of 2s and 2p orbitals of oxygen to the bonding state is always higher than those of the boron. Moreover, because the B-O spacing in silicon is larger, the electronic density of states (DOS) B and O are decreased by the bonding with the silicon atoms, and the bonding strength of B-O pair in silicon is lower than those in boron oxide and vacuum. The decrease in the DOS and the bonding strength is also supported by the fact that the atomic population is also decreased by the silicon environment.