Laser pulse duration dependence of blister formation on back-radiated Ti thin films for BB-LIFT

Abstract

The influence of the laser pulse duration on the mechanism of blister formation in the particle transfer technique, blister-based laser-induced forward transfer, was investigated. Pulses from a fs Ti:Sapphire laser (120 fs, 800 nm) and from a ns Nd:YAG laser (7 ns, 532 nm) were used to directly compare blister formation on thin titanium films of ca. 300 nm thickness, deposited on glass. The different blister morphologies were compared and contrasted by using optical microscopy and atomic force microscopy. The results provide evidence for different blister formation mechanisms: for fs pulses the mechanism is predominantly ablation at the metal-glass interface accompanied by confined plasma expansion and deformation of the remaining metal film; for ns pulses it is heating accompanied by thermal expansion of the metal film.

Blister-based-laser-induced-forward-transfer: a non-contact, dry laser-based transfer method for nanomaterials

“…The temperatures fitted for the fast, thermal components (1500 K and 2000 K respectively) correlate very well with the expected surface temperature of the metal film, as estimated in a previous publication 6 . The flow velocity is related to collisions in the desorption plume and is expected to be larger for the higher fluence where all molecules are desorbed from the area corresponding to the blister region, leading to an increase in collisions during desorption and a correspondingly higher flow velocity.…”

“…8. As was shown previously, the blisters obtained with ns irradiation have a larger diameter than those formed with fs radiation for similar laser spot dimensions 6 . This is a consequence of the fs laser blister corresponding to the area within the laser pulse where the energy is sufficient to cause ablation of the underside of the metal film.…”

Surface adhesion of back-illuminated ultrafast laser-treated polymers

“…1(a). Earlier reports involving blister formation in thin films of polyimide and titanium using 355 nm and 800 nm laser wavelengths, lack the direct experimental evidence of confined chemical changes at the interface [5,11,29,30]. Our observation of confined chemical changes provides direct experimental evidence for confinement of chemical changes only at the interface induced by an ultrafast laser [5][6][7][8][29][30][31][32][33][34][35][36][37][38][39][40][41].…”

“…The use of ultrafast pulses for local energy deposition in materials has several applications in 3D optical data storage [1,2], integrated optics [3][4][5], and laser-induced forward transfer (LIFT) [6][7][8][9][10][11]. In contaminant-free LIFT, the nonlinear interaction of an ultrafast pulse with the polymer film (often called a dynamic release layer) between a glass substrate and transfer material ensures the confinement of the energy deposition to the glass-polymer interface, leaving the transfer material chemically intact [12].…”

The morphological and compositional changes of bimetallic Ti/Al thin film induced by ultra-short laser pulses

“…), and an environment during radiation [5]. Up to now, the individual thin films and their combinations have been studied regarding irradiation with short nanosecond (ns) [6,7] and ultra-short picosecond and femtosecond (ps and fs) laser pulses [8][9][10][11][12][13][14]. In the case of fs pulses, this method allows extremely precise modifia e-mail: biljagak@vin.bg.ac.rs (corresponding author) cations, on the micrometre and even on the nanometre scale.…”