Accession Number:

ADP012240

Title:

The Role of the Interfaces in the Optical Effects of Large-Sized SiC(x)O(1-x)N Nanocrystallites

Descriptive Note:

Corporate Author:

MILITARY UNIV OF TECHNOLOGY WARSAW (POLAND) DEPT OF ELECTRONICS

Report Date:

2001-11-01

Pagination or Media Count:

6.0

Abstract:

The band energy structure of large-sized 10-25 nm nanocrystallites NC of SiCxO1-xN 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 SiCxO1-xN crystalline layers. Numerical modeling shows that these NC may be treated as quantum dot-like SiCxO1-xN 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.

Subject Categories:

  • Inorganic Chemistry

Distribution Statement:

APPROVED FOR PUBLIC RELEASE