Nanoparticle detection limits of TNO's Rapid Nano: modeling and experimental results

TNO has developed the Rapid Nano scanner to detect nanoparticles on EUVL mask blanks. This scanner was designed to be used in particle qualifications of EUV reticle handling equipment. In this paper we present an end-to-end model of the Rapid Nano detection process. All important design parameters concerning illumination, detection and noise are included in the model. The prediction from the model matches the performance that was experimentally determined (59 nm LSE). The model will be used to design and predict the performance of future generations of particle scanners.