Page 68 - High Power Laser Handbook

40 G a s , C h e m i c a l , a n d F r e e - E l e c t r o n L a s e r s Excimer Lasers 41

Second-generation superconductor bands are built from a multi-
layer structure. The base is a stainless steel band that takes the mechan-
ical forces onto which the multiple functional layers are deposited.
The cerium oxide (CeO ) buffer layer and the superconducting
2
YBaCuO layer are typically produced by pulsed laser deposition
16
(PLD) with 308-nm excimer lasers. Within a vacuum chamber, the
excimer laser ablates small portions from the target material (i.e., the
YBaCuO) with each pulse. From the resulting plasma plume, a directed
transfer of the target material is achieved, which is then deposited on
the substrate. Tight control of the laser conditions leads to optimum
ablation and a uniform deposition of the thin film.
The application range of high-power excimer lasers is steadily
increasing, as driven by the industry trends toward miniaturization and
cost-effective processing, including the elimination of wet chemistry.
The excimer laser technology demanded by various applications and
industries has been developed to a very mature stage. Future require-
ments of even higher power levels, in excess of 1 kW, and of further cost
reductions in the laser process are the driving forces behind advancing
excimer laser technology and paving the way for new opportunities.

References

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