Issue 32, 2014

Role of vacancies to p-type semiconducting properties of SiGe nanowires

Abstract

Many experiments have shown that both composition-randomly-distributed Si1−xGex nanowires (NW) and the Ge/Si core/shell NW possess excellent p-type semiconducting properties without relying on any doping strategy. Vacancies in both NW are believed to play a key role in the p-type semiconducting properties. To gain deeper insights into the role of vacancies, we performed first-principle calculations to systematically study the effects of single Si or Ge vacancies in four distinct SiGe NW, namely, randomly-distributed triangular-prism (RTP) NW, fused triangular-prism (FTP) NW, the GecoreSishell NW and SicoreGeshell NW. We find that the tendency for vacancy formation depends strongly on the structures of the NW. The defective RTP, FTP and GecoreSishell NW show promising p-type semiconducting properties while the defective SicoreGeshell NW does not. The Si vacancies in the inner region are attributed to the p-type properties of the RTP NW, and both the Si and Ge vacancies at the core/shell interfaces are attributed to the p-type properties of the FTP and the GecoreSishell NW. Our results show how the vacancies affect the electronic structures and the semiconducting properties of different SiGe NW, and offer an explanation of why the synthesized Si1−xGex and GecoreSishell NW possess excellent p-type semiconducting properties without relying on any doping strategy.

Graphical abstract: Role of vacancies to p-type semiconducting properties of SiGe nanowires

Supplementary files

Article information

Article type
Paper
Submitted
09 May 2014
Accepted
06 Jun 2014
First published
06 Jun 2014
This article is Open Access
Creative Commons BY license

J. Mater. Chem. C, 2014,2, 6536-6546

Author version available

Role of vacancies to p-type semiconducting properties of SiGe nanowires

R. Zhou, B. Qu, B. Zhang, P. Li and X. C. Zeng, J. Mater. Chem. C, 2014, 2, 6536 DOI: 10.1039/C4TC00958D

This article is licensed under a Creative Commons Attribution 3.0 Unported Licence. You can use material from this article in other publications without requesting further permissions from the RSC, provided that the correct acknowledgement is given.

Read more about how to correctly acknowledge RSC content.

Social activity

Spotlight

Advertisements