As EUV approaches high volume manufacturing, reticle defectivity becomes an even more relevant topic for further investigation. Current baseline strategy for EUV defectivity management is to design, build and maintain a clean system without pellicle. In order to secure reticle front side particle adders to an acceptable level for high volume manufacturing, EUV pellicle is being actively investigated. Last year ASML reported on our initial EUV pellicle feasibility. In this paper, we will update on our progress since then. We will also provide an update to pellicle requirements published last year. Further, we present experimental results showing the viability and challenges of potential EUV pellicle materials, including, material properties, imaging capability, scalability and manufacturability.

As the predecessor for Extreme Ultraviolet Lithography (EUVL) production tools, ASML is realizing a development exposure tool, the alpha demo tool. The main objectives for undertaking this effort are to minimize the risks of changing to a new lithographic technology in production and to support the development ofthe global infrastructure of masks, sources, and resist. For this, initial imaging of the alpha demo tool is aimed at features consistent with the 45-nm technology node. In this paper we will present the status of the realization of the alpha demo tool. Several modules of the system have been integrated in the main body, and results of the system (vacuum) performance will be presented along with the wafer stage servo performance and wafer handler performance. We will summarize the current status of EUV sources including the recent work on alternatives to using Xe, report on our in-house source research, and provide an update on the fabrication of EUV optics. Polishing data of the projection optics mirrors shows that not only have we realized the requirements for 45-nm imaging, but also are we well underway in meeting the imaging requirements for production EUVL at the 32-nm node and beyond. Finally, since key to the commercial success of EUVL will be the availability of the infrastructure for reticles and resist, we will summarize the general status of EUV masks and resist.

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Microwave reflectance probed photoconductivity (or µ-PCD) measurement represents a contactless and non-invasive method to characterize impurity content in semiconductors. Major drawbacks of the method include a difficult separation of reflectance due to dielectric and conduction effects and that the µ-PCD signal is prohibitively weak for highly conducting samples. Both of these limitations could be tackled with the use of microwave resonators due to the well-known sensitivity of resonator parameters to minute changes in the material properties combined with a null measurement. A general misconception is that time resolution of resonator measurements is limited beyond their bandwidth by the readout electronics response time. While it is true for conventional resonator measurements, such as those employing a frequency sweep, we present a time-resolved resonator parameter readout method which overcomes these limitations and allows measurement of complex material parameters and to enhance µ-PCD signals with the ultimate time resolution limit being the resonator time constant. This is achieved by detecting the transient response of microwave resonators on the timescale of a few 100 ns during the µ-PCD decay signal. The method employs a high-stability oscillator working with a fixed frequency which results in a stable and highly accurate measurement.