Gigaphoton’s LPP Light Source for Mass-Production Generates 7 W of EUV Power

Gigaphoton declared that its high-volume manufacturing laser-produced plasma (LPP) light source, slated for shipping in 2012, has produced an extreme ultraviolet (EUV) power of 7 W.

This result was obtained by irradiating a tin target (Sn droplet) with a combination of 2.7 kW, 90 kHz CO₂ laser main pulse and a solid-state laser pre-pulse. The LPP light source running at 30% duty cycle /h generated up to 0.3 mJ, 27 W EUV light at the plasma point. The achievement of this landmark will help Gigaphoton to carry on its development program and enhance the source to reach an output of 250 W.

Since 2002, Gigaphoton has involved in the advancement of LPP light sources for use in EUV lithography applications in order to achieve better cost of operation and output. This declaration corroborates that the company has designed an LPP light source for mass production by integrating advanced elemental technologies previously validated in experimental systems.

The LPP light source produces the EUV energy when a 20-µm-diameter Sn droplet was irradiated by a CO₂ laser. The EUV energy release is then followed by the possible deposition of remaining tin debris such as tin atoms and tin fragments on the collector mirror, thus causing damage to the multi-layer film of the mirror, decreasing power output and reflectance.

Gigaphoton's magnetic debris mitigation technology integrates the main pulse produced by a CO₂ laser and the pre-pulse produced by a solid-state laser to eliminate formation of any tin fragments and neutralize tin atoms by ionizing a majority of the material in every droplet. These ionized particles are then magnetically removed by the Sn catcher, thus reducing deposition and protecting the collector mirror from getting damaged.

The 193 nm ArF immersion lithography as double-pattern nears its resolution limit. EUV's very-smaller 13.5 nm wavelength is considered as the next-generation lithography system to back Moore's Law for several future-generation devices. A low-cost, powerful and reliable EUV energy source is yet to be developed in order to realize a commercially feasible EUV lithography scanner. Gigaphoton is focused on delivering a suitable technical and commercial EUV source to the semiconductor industry.