Ultrafast laser processing of materials: from science to industry
Processing of materials by ultrashort laser pulses has evolved significantly over the last decade and is starting to reveal its scientific, technological and industrial potential. In ultrafast laser manufacturing, optical energy of tightly focused femtosecond or picosecond laser pulses can be delivered to precisely defined positions in the bulk of materials via two /multi photon excitation on a timescale much faster than thermal energy exchange between photoexcited electrons and lattice ions. Control of photo ionization and thermal processes with the highest precision, inducing local photomodification in sub 100 nm sized regions has been achieved. State of the art ultrashort laser processing techniques exploit high 0.1 1 mm spatial resolution and almost unrestricted three dimensional structuring capability. Adjustable pulse duration, spatiotemporal chirp, phase front tilt and polarization allow control of photomodification via uniquely wide parameter space. Mature opto electrical/mechanical technologies have enabled laser processing speeds approaching meters per second, leading to a fast lab to fab transfer. The key aspects and latest achievements are reviewed with an emphasis on the fundamental relation between spatial resolution and total fabrication throughput. Emerging biomedical applications implementing micrometer feature precision over centimeter scale scaffolds and photonic wire bonding in telecommunications are highlighted.
Light, science applications