Element Six has released a diamond optics range with more than 10 times higher damage threshold for high power CO2 laser applications. The Diamond PureOptics dispense with anti-reflective (AR) thin film coatings – traditionally the weak point of diamond optics – and replace them with a diamond structured surface designed to reduce reflection losses. This shifts the reliance of the optics solely onto the intrinsic properties of diamond to withstand multi-kilowatt CO2 laser systems.
‘With the industry trending to even more powerful CO2 laser sources and the high costs associated with system downtime, the need for more durable and reliable anti-reflective laser windows is critical,’ said Bruce Bolliger, head of sales and marketing at Element Six Technologies.
One application for the optics is in extreme ultraviolet (EUV) lithography systems, which use CO2 lasers to generate sub 10nm radiation for patterning small structures on semiconductor chips. High-power CO2 lasers are also being used more often in industrial processing.
‘Creating an all-diamond solution increases durability and enables higher power by eliminating more vulnerable anti-reflection thin films, which are often the first to fail in extremely high power density applications such as EUV lithography. We are confident the enhanced performance of our Diamond PureOptics optical windows will enable the next generation of high power laser systems and advanced applications,’ Bolliger added.
Research comparing the performance of AR coated windows with Element Six’s new optics demonstrated the superiority of MS in regards to reliability and thermal management, according to the company. While in bench marked tests AR coated windows demonstrated a laser induced damage threshold at ~0.25 MW/cm2,the same laser was unable to damage the MS window at all, even at power densities 10 times higher.
Additionally, exchanging AR coatings with MS decreased overall window absorption, helping to keep window operating temperatures low and minimise thermally induced beam distortion.