Effect of size and surface structure manipulation on the luminescent properties of silicon nanoclusters

Structures measuring several nanometers in any dimension represent a transitional scale between materials with crystalline order and molecules. Quantum confinement of the carrier wavefunction within such structures may significantly alter their electronic behavior. Additionally, the effect of surface reconstruction becomes substantial at this scale. This work investigated electronic and structural properties of silicon nanoclusters. Electrochemical etching was used to produce particles smaller than 3 nm in diameter. Electron microscopy and material analysis studies showed the particles to have a crystalline silicon core with significant structural reconstruction on the surface. Also, the clusters were found to be spherical in shape and quantized in size below 3 nm in diameter. The efficient luminescence of the material was studied and interpreted through the existing luminescence models. Surface modifications leading to functionalization were carried out. Both structural and luminescent characteristics of the modified clusters were studied, revealing a weak dependence of the luminescence efficiency on exchanging the surface hydrogen atoms for other single bonded species. The observed optical activity of silicon nanoclusters makes them an important material for a variety of scientific applications.

Name thesis:degree_name

Ph.D.

Level thesis:degree_level

Dissertation

Discipline thesis:degree_discipline

Physics

Year dc:date

2012

Author dc:creator

• Belomoin, Gennadiy A.

Contributors dc:contributor

• Nayfeh, Munir H.

• quantum confinement
• surface reconstruction
• silicon nanoclusters
• electrochemical etching
• luminescence efficiency

Statement dc:rights

• ©2006 Belomoin

Language dc:language

en

Identifier

Q. 539.6 Tc6b
FILM 2006 B418

OAI identifier oai:identifier

oai:www.ideals.illinois.edu:2142/32090