The Role of the Interfaces in the Optical Effects of Large-Sized SiC(x)O(1-x)N Nanocrystallites
Abstract
The band energy structure of large-sized (10-25) nm nanocrystallites (NC) of SiC(x)O(1-x)N (0.96 < x < 1.06) was investigated using different band energy approaches. as well as modified Car Parinello molecular dynamics simulations of interfaces. A thin carbon sheet (of about 1 nm) appears, covering the crystallites. This sheet leads to substantial reconstruction of the near-the-interface SiC(x)O(1-x)N crystalline layers. Numerical modeling shows that these NC may be treated as quantum dot-like SiC(x)O(1-x)N reconstructed crystalline surfaces, covering the appropriate crystallites. All band energy calculation approaches (semi-empirical pseudopotential, fully augmented plane waves and norm-conserving self-consistent pseudopotential approaches) predicted the experimental spectroscopic data. In particular, it was shown that the near-the-surface carbon sheet plays a dominant role in the behavior of the reconstructed band energy structure. Independent evidence for the important role of the dot-like crystalline layers are the excitonic-like states, which are not dependent on the particular structure of the SiC, but are sensitive to the thickness of the carbon layer.
Document Details
- Document Type
- Technical Report
- Publication Date
- Nov 01, 2001
- Accession Number
- ADP012240
Entities
People
- H. Kaddouri
- I. V. Kityk
- K. J. Plucinski
Organizations
- Military University of Technology