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As the traditional techniques used in optical photolithography at 193 nm are running out of steam and are becoming
prohibitively expensive, a new cost-effective, high power EUV (extreme ultra-violet) light source is needed to enable
high volume manufacturing (HVM) of ever shrinking semiconductor devices. XTREME technologies GmbH and EUVA
have jointly developed tin based LDP (Laser assisted Discharge Plasma) source systems during the last two years for the
integration of such sources into scanners of the latest and future generations. The goals of the consortium are 1) to solve
the wavelength gap - the growing gap between the printed critical dimensions (CD) driven by Moore's Law and the
printing capability of lithographic exposure tools constrained by the wavelength of the light source - and 2) to enable the
timely availability of EUV light sources for high volume manufacturing.
A first Beta EUV Source Collector Module (SoCoMo) containing a tin based laser assisted discharge plasma source is in
operation at XTREME technologies since September 2009. Alongside the power increase, the main focus of work
emphasizes on the improvement of uptime and reliability of the system leveraging years of experience with the Alpha
sources. Over the past period, a cumulated EUV dose of several hundreds of Mega Joules of EUV light has been
generated at the intermediate focus, capable to expose more than a hundred thousand wafers with the right dose stability
to create well-yielding transistors. During the last months, the entire system achieved an uptime - calculated according to
the SEMI standards - of up to 80 %. This new SoCoMo has been successfully integrated and tested with a pre-production
scanner and is now ready for first wafer exposures at a customer's site. In this paper we will emphasize what our
innovative concept is against old type of Xe DPP and we will present the recent status of this system like power level,
uptime and lifetime of components as well.
In the second part of the paper the EUV source developments for the HVM phase are described. The basic engineering
challenges are thermal scaling of the source and debris mitigation. Feasibility of the performance can be demonstrated by
experimental results after the implementation into the beta system. The feasibility of further efficiency improvement,
required for the HVM phase, will also be shown. The objectives of the HVM roadmap will be achieved through
evolutionary steps from the current Beta products.
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