Laser-induced structural and composition modification of multilayered Ni/Ti thin film in air and liquids

Abstract

The interaction of an Er, Yb, Cr-glass laser, operating at 1540 nm wavelength and a pulse duration of 40 ns, with Ni/Ti multilayer thin films has been studied. Five (Ni/Ti) bilayers deposited by DC ion sputtering on Si(100) wafers to a total thickness of about 180 nm were treated with laser fluences of about 6.4 and 8.8 J cm −2 . Single and multi-pulse laser irradiation was done at normal incidence in air, water and ethanol ambients. The composition and surface morphology were monitored by particle-induced x-ray emission, Rutherford backscattering spectrometry (RBS), scanning electron microscopy and profilometry. Most of the absorbed laser energy was rapidly transformed into heat, producing intensive modifications of composition and morphology on the target surface. The results show an increase in surface roughness, formation of parallel periodic surface structures, appearance of hydrodynamic features and ablation of surface material. RBS analysis revealed that laser modification induced inter-mixing between the components of individual Ni and Ti layers, with indications of the formation of NiTi intermetallic compounds. An interesting finding is the morphological changes dominant in the Si substrate, whereas the Ni/Ti multilayer structure has mainly undergone changes in the chemical composition.

Laser-induced modification of 5x(Ni/Pd)/Si and (Ni/Pd)/Si systems by picosecond pulses

“…Intenzitet tog maksimuma se povećao na periferiji usled nagomilavanja materijala. Posle dejstva bilo kojim brojem impulsa uočeno je pomeranje maksimuma ka nižim vrednostima energije, kao i pomeranje visokoenergetske ivice Si, što je posledica međusobnog mešanja komponenti najverovatnije izazvanog termički aktiviranom difuzijom [13].…”

Особенности Структурирования И Абляции Тонких Пленок Титана Фемтосекундными Лазерными Импульсами

“…Откольная абляция совместно со структурированием поверхности занимают особое место в технологиях многослойных пленок. Одна из уникальных возможностей таких процессоввозможность селективно воздействовать только лишь на верхний слой многослойного образца, не повреждая нижележащие [5,6], однако поиск оптимальных режимов деликатного воздействия все еще продолжается.…”

Features of structuring and ablation of thin titanium films by femtosecond laser pulses

“…The spallation ablation together with surface structuring have a special place in multilayer film technologies. One of the unique capabilities of such processes is a selective action on only the upper layer of a multilayer specimen without damaging the underlying layers [5,6], however, the search for optimum gentle action conditions is still under way.…”