Proceedings Article | 11 February 2011
Proc. SPIE. 7925, Frontiers in Ultrafast Optics: Biomedical, Scientific, and Industrial Applications XI
KEYWORDS: Ultrafast phenomena, Aerospace engineering, Laser applications, Laser drilling, Laser ablation, Thermal effects, Picosecond phenomena, Disk lasers, Pulsed laser operation, Plasma
This paper demonstrates that disk-laser technology introduces advantages that increase efficiency and
allows for high productivity in micro-processing in both the nanosecond (ns) and picosecond (ps) regimes.
Some technical advantages of disk technology include not requiring good pump beam quality or special
wavelengths for pumping of the disk, high optical efficiencies, no thermal lensing effects and a possible
scaling of output power without an increase of pump beam quality. With cavity-dumping, the pulse
duration of the disk laser can be specified between 30 and hundreds of nanoseconds, but is independent of
frequency, thus maintaining process stability. TRUMPF uses this technology in the 750 watts average
power laser TruMicro 7050. High intensity, along with fluency, is important for high ablation rates in thinfilm
removal. Thus, these ns lasers show high removal rates, above 60 cm<sup>2</sup>/s, in thin-film solar cell
production. In addition, recent results in paint-stripping of aerospace material prove the green credentials
and high processing rates inherent with this technology as it can potentially replace toxic chemical
processes. The ps disk technology meanwhile is used in, for example, scribing of solar cells, wafer dicing
and drilling injector nozzles, as the pulse duration is short enough to minimize heat input in the laser-matter
interaction. In the TruMicro Series 5000, the multi-pass regenerative amplifier stage combines high
optical-optical efficiencies together with excellent output beam quality for pulse durations of only 6 ps and
high pulse energies of up to 0.25 mJ.
