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Nanomat 2019
Nano Research & Applications
ISSN: 2471-9838
Page 36
January 28-29, 2019
Barcelona, Spain
18
th
Edition of International Conference on
Emerging Trends in
Materials Science and
Nanotechnology
L
aser processing of materials is unique method which allows
their morphological as well as composition modifications. In
case of usage of ultra-short laser pulses (pulse duration less than
picosecond) the laser processing is extremely precise. Irradiation
ofmaterials by femtosecond laser enables removal or alterationof
their surface at nano/micro level without change of non-irradiated
area. Nano scale multilayer thin films are attractive composite
materials due to their properties that cannot be obtained in the
caseofmaterials of the same bulk constituents. Selective ablation
of the upper layer of the nanolayer thin film with little or without
damage of the layer or the substrate beneath is significant for
applications. The effects of ultra-short laser pulses on reactive
titanium-aluminium (Ti/Al) and nickel-titanium (Ni/Ti) nano-layer
thin films (NLTF) were investigated. The samples composed of
five bilayers (Ti/Al and Ni/Ti respectively) were prepared by ion
sputtering on a Si substrate. Single pulse irradiations were done
in air by focusing and with linearly polarized gaussian laser beam
of 515 nm wavelength, 200 fs pulse duration and variable pulse
energy. One step selective ablation of upper layer from NLTFs at
low laser pulse energies (Figure 1 and 2) and complete ablation
of the thin films from the Si substrate at higher pulse energies
were registered. Effects of laser induced morphological and
composition changes were monitored by scanning electron
microscopy/energy dispersive x-ray spectroscopy (SEM & EDS)
and profilometry. Spalative ablation could be themainmechanism
that caused ablation of the upper layers from the nanolayer thin
films.
biljagak@vin.bg.ac.rsSelective ablation of nanolayer Ti based thin
films by single pulse femtosecond laser
Biljana Gaković
Vinča Institute of Nuclear Sciences, Serbia
Nano Res Appl 2019, Volume 5
DOI: 10.21767/2471-9838-C1-031