Size dependent optical properties of Si quantum dots in Si-rich nitride/Si3N4 superlattice synthesized by magnetron sputtering

Yong-Heng So, Angus Gentle, Shujuan Huang, Gavin Conibeer, Martin A. Green

Research output: Contribution to journalArticle

22 Citations (Scopus)

Abstract

A spectroscopic ellipsometry compatible approach is reported for the optical study of Si quantum dots (QDs) in Si-rich nitride/silicon nitride (SRN/Si3N4) superlattice, which based on Tauc-Lorentz model and Bruggeman effective medium approximation. It is shown that the optical constants and dielectric functions of Si QDs are strongly size dependent. The suppressed imaginary dielectric function of Si QDs exhibits a single broad peak analogous to amorphous Si, which centered between the transition energies E1 and E2 of bulk crystalline Si and blue shifted toward E2 as the QD size reduced. A bandgap expansion observed by the TL model when the size of Si QD reduced is in good agreement with the PL measurement. The bandgap expansion with the reduction of Si QD size is well supported by the first-principles calculations based on quantum confinement.
Original languageEnglish
Article number064302
Pages (from-to)1-5
Number of pages5
JournalJournal of Applied Physics
Volume109
Issue number6
DOIs
Publication statusPublished - 15 Mar 2011
Externally publishedYes

Fingerprint Dive into the research topics of 'Size dependent optical properties of Si quantum dots in Si-rich nitride/Si<sub>3</sub>N<sub>4</sub> superlattice synthesized by magnetron sputtering'. Together they form a unique fingerprint.

  • Cite this