Characterization and simulation of optical absorption in Si nanocrystals

Xuguang Jia, Lingfeng Wu, Ziyun Lin, Tian Zhang, Terry Chien Jen Yang, Hongze Xia, Binesh Puthen-Veettil, Gavin Conibeer, Ivan Perez-Wurfl

Research output: Chapter in Book/Report/Conference proceedingConference PaperOther

1 Citation (Scopus)

Abstract

The application of silicon quantum dot (Si QD) based material is regarded as a promising approach for the realization of high efficiency solar cells. When silicon nanocrystals are made very small (within the vicinity of the exciton Bohr radius of bulk Si), they behave as quantum dots due to the three-dimensional quantum confinement, which could cause the material's effective optical band gap to increase. The optical band gap can be deduced from the absorption coefficient. In this paper, we analyze optical absorption and emission processes in Si QD and attempt to simulate the band-edge absorption features based on the photoluminescence spectrum. We also investigate the application of ellipsometry in the study of optical properties of Si QD thin films. Based on WVASE32 modeling tool, a homogeneous mixture model is developed to extract the absorption coefficient of this material. From these results, we extract the effective optical band gap and analyze optical properties of Si QDs materials.

Original languageEnglish
Title of host publicationSpecial Issue
Subtitle of host publicationE-MRS 2014 Spring Meeting – Symposium H: ALTECH 2014
PublisherJohn Wiley & Sons
Pages271-274
Number of pages4
DOIs
Publication statusPublished - 1 Mar 2015
Externally publishedYes

Publication series

NamePhysica Status Solidi. C: Current Topics in Solid State Physics
PublisherJohn Wiley & Sons, Inc.
Number3
Volume12
ISSN (Print)1862-6351
ISSN (Electronic)1610-1642

Keywords

  • Absorption coefficient
  • Band gap extraction
  • Ellipsometry
  • Photoluminescence
  • Silicon nanocrystals

Cite this