Nanoparticles and thin film formation in ultrashort pulsed laser deposition of vanadium oxide.
The ultrashort pulsed laser deposition of vanadium oxide thin films has been carried out by a frequency-doubled Nd:glass laser with a pulse duration of 250 fs. The characteristics of the plasma produced by the laser-target interaction have been studied by ICCD imaging and optical emission spectroscopy. The results confirm that an emitting plasma produced by ultrashort laser pulses is formed by both a primary and a secondary component. The secondary component consists of particles with a nanometric size, and their composition and spatial angular distribution influence the deposited films. In fact, these films, analyzed by X-ray photoelectron spectroscopy, X-ray diffraction, scanning electron microscopy, and atomic force microscopy, are formed by the aggregation of a large number of nanoparticles whose composition is explained by a model based on equilibrium thermal evaporation from particles directly ejected from the target. On these basis, the presence in the films of a mixture of V(2)O(5) and VO(2) is discussed.
Teghil
Roberto
R
Dipartimento di Chimica, Università della Basilicata, Via N. Sauro 85, 85100 Potenza, Italy. roberto.teghil@unibas.it
D'Alessio
Luciano
L
De Bonis
Angela
A
Galasso
Agostino
A
Ibris
Neluta
N
Salvi
Anna Maria
AM
Santagata
Antonio
A
Villani
Patrizia
P