Near-field investigation of porous silicon photoluminescence modification after oxidation in water.
We report on local photo-induced oxidation of porous silicon in water at room temperature. Starting from a nonluminescent sample, the oxidation process induces luminescence which was found to first increase and then decrease as a function of the oxidation time. A clear blue shift is also observed. This effect is believed to be owing to size modification of silicon nanocrystallites and thus is explained in terms of quantum confinement. Optical near-field images and spectrum are used to monitor the photoluminescence modifications after oxidation. As the photoluminescence can be widely tuned in wavelength and intensity, this method offers a way to pattern the emission properties of the sample.
Juan
M
M
ICD CNRS FRE 2848, Univ. de Technologie de Troyes, Laboratoire de Nanotechnologie et d' Instrumentation Optique, 12 rue Marie Curie, BP 2060, 10010 Troyes Cedex, France.
Bouillard
J-S
JS
Plain
J
J
Lerondel
G
G
Adam
P M
PM
Bachelot
R
R
Royer
P
P