|
EUVL is considered to be one of the most attractive candidates to succeed conventional optical lithography in the coming years. This will permit reduction of structure sizes in semiconductor devices to less than 45 nm. To enable this technology, a light source is required that emits in the spectral range around 13.5 nm. The LPP EUV source has great potential to be the future source for EUVL, and offers several advantages over discharge-based EUV sources. These advantages can be summarized as power scalability through tuning of laser parameters, low debris, pulse-to-pulse stability (optimum dose control), flexibility in dimensions, spatial stability, minimal heat load, and large solid angle of collection.
The main objective of the EUV program at Powerlase is to develop a high-power, cost-effective source able to deliver enough usable power for use in the microlithography process. We have successfully generated a high-power EUV source using an LPP scheme. In this scheme, we spatially multiplex (combine) several of our lasers and focus them onto a xenon target. To achieve this we have recently made significant steps forward in the performance of the laser-driver module employed in our LPP EUV source. We have increased the average power output from the laser whilst minimizing the overall cost of ownership (CoO) and footprint of the system.
In addition to sustained laser development, we are taking the responsibility of developing an appropriate target to achieve what we have projected in our EUV development source roadmap. The target development is not restricted to Xe solid jets, but other targets materials are also investigated in order to increase the inband EUV conversion efficiency (CE). The combination of highly efficient lasers and high CE of the inband EUV through target development drives down the CoO of the EUV source.
|
