The effect of laser wavelength on the ablation rate of carbon

Abstract

The ablation of graphite is studied as a function of laser fluence for 355, 532 and 1,064 nm wavelength generated by a nanosecond Nd:YAG laser. It has been found that in the case of lower wavelengths, the transition from the thermal ablation to the phase explosion takes place at lower laser fluences. The change of crater shape due to the effect of deep drilling in the proximity of the phase explosion threshold was observed. The calculations of plasma radiation flux to the target surface were made, and the considerable increase of absorbed energy density was found in the case of 355 nm wavelength.

Laser ablation- and plasma etching-based patterning of graphene on silicon-on-insulator waveguides

“…This ablation threshold is higher than the value found by Zhang et al [21], but we also worked at a longer wavelength, namely 1030 nm versus 800 nm. This seems to be in line with earlier wavelength dependence studies [22]. The smallest measured diameter of the ablated spot was 8 μm, which in combination with highprecision alignment stages enables patterning of graphene with micron-scale resolution.…”

Impacts of Ambient and Ablation Plasmas on Short- and Ultrashort-Pulse Laser Processing of Surfaces

“…The explanation of ultradeep drilling was supported recently by comprehensive experimental and theoretical studies performed by Hoffman et al [51] using 355, 532 and 1064 nm wavelengths generated by a nanosecond Nd:YAG laser. It was found that at lowest wavelength, the transition from thermal ablation to phase explosion takes place at lower laser fluences.…”

“…While the role of the recoil pressure of plasma plumes under PLA is extensively discussed in the literature (see, e.g., [46][47][48][49]), detailed analysis of the plasma reradiation effects on the ablation process is still lacking. Only recently comprehensive experimental and theoretical studies were performed, which have shown that the radiating laser-ablation plasma can dramatically influence the ablation dynamics, leading to the formation of ultradeep craters [50][51][52]. On the example of graphite, it was clearly demonstrated that ultradeep crater formation can only be explained based on the concept of ablation plasma absorption and reradiation [50,51].…”

“…Only recently comprehensive experimental and theoretical studies were performed, which have shown that the radiating laser-ablation plasma can dramatically influence the ablation dynamics, leading to the formation of ultradeep craters [50][51][52]. On the example of graphite, it was clearly demonstrated that ultradeep crater formation can only be explained based on the concept of ablation plasma absorption and reradiation [50,51]. Graphite, which melts at pressures ≥100 bar and has a relatively small gap between the melting and boiling temperatures at the same pressure, is the brightest example of the plasma feedback effect though the latter has a universal character regarding the type of material [52].…”

WB2 to WB3 phase change during reactive spark plasma sintering and pulsed laser ablation/deposition processes

“…This material is vaporized from the target, forms a plasma plume, and subsequently deposits as a thin film on a substrate. The ejected species expand into the surrounding vacuum (or ambient gas) in the form of a plume containing many energetic species including atoms, molecules, electrons and ions [26,27] prior to deposition on the substrate. After deposition of the evaporated material on the surface of the substrate, its re-synthesis occurs.…”