화학공학소재연구정보센터
Applied Surface Science, Vol.387, 1188-1194, 2016
Fluence dependent electrical conductivity in aluminium thin films grown by infrared pulsed laser deposition
We studied the effect of laser fluence on the morphology, composition, structure and electric conductivity of deposits generated by pulsed laser ablation of a metallic aluminium target in vacuum using a Q-switched Nd:YAG laser (1064 nm, 15 ns). Upon irradiation for one hour at a repetition rate of 10 Hz, a smooth layer of several tens of nanometres, as revealed by atomic force microscopy (AFM) was deposited on glass. Surface chemical composition was determined by X-ray photoelectron spectroscopy, and to study the conductivity of deposits both I-V curves and conductive-AFM measurements were performed. Irradiation at fluences around 2.7 J/cm(2) resulted in deposition of amorphous aluminium oxide films. Differently, at higher fluences above 7 J/cm(2), the films are constituted by metallic aluminium. Optical emission spectroscopy revealed that highly ionized species are more abundant in the ablation plumes generated at higher fluences. The results demonstrate the possibility to control by PLD the metal or dielectric character of the films. (C) 2016 Elsevier B.V. All rights reserved.