Ultrafast laser cleaning – The light touch

Laser Cleaning is a cutting-edge technique designed for removal of contamination layers from solid surfaces by irradiating the surface with a laser beam. It is a non-contact process, which does not require the use of chemicals or abrasives, eliminating problems of chemical toxicity, corrosive residues, erosion and erasure of surface structure. Commercially available industrial laser cleaning systems use high power nanosecond lasers. However, they deposit considerable heat load into the objects being cleaned, as the primary ablation mechanism is thermally activated. It causes heat related physical and/or chemical changes, surface damage and potentially bulk material property change.

Researchers at the Laser Physics Centre (LPC), Research School of Physics, the Australian National University, have developed a multi-wavelength Ultrafast Laser Cleaning (ULC) system, combining together several advanced laser technologies: up to km/s laser scanning speed, µm-precise beam positioning, large area processing with telecentric scanning optics, variable spot shape, and spectral analysis of the ablated plume. Based on a new class of powerful ultrafast lasers, ULC is now reaching the so called “cold ablation” regime where high average power can be used without introducing thermal effects. This enables large increases in material throughput at industrially relevant speeds. ULC is an amazing tool to clean and enhance surfaces in a way not possible with any other method.

A recent successful collaboration activity between LPC and CGA (Centre for Gravitational Astrophysics, ANU) for the Australian National Fabrication Facility network is the large-scale fast cleaning of an essential part for their Ion Beam Sputter system. Maintenance work on Ion Beam Sputter system requires the removal of excess material deposited around the machine's chamber. The grids used on the radio frequency Ion Beam Source must be cleaned with the utmost care. Any deformation in the profile of the grids may significantly change the ion beam's profile. This cleaning is either performed with concentrated hydrofluoric acid (dangerous and producing toxic waste), or sandblasting (significant risk of deforming the grids). ULC avoids all these technological obstacles within a processing time of only few minutes.

Faster, safer, more precise, ULC is an ideal alternative for material removal.

Team

Rapp, Ludovic profile

Madden, Stephen profile
(02) 612 58574

Rode, Andrei profile
(02) 612 54637

Zinnecker, Victoria profile
PhD Student

Brand, Julia profile

Updated:  30 September 2020/ Responsible Officer:  Head of Laser Physics/ Page Contact:  Physics Webmaster