Presented at SPIE 2008

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Introduction

New complex transistors architectures expand application space of the scatterometry beyond measurements of the simple photoresist and a-Si gratings towards characterization of more complex structures. It has been suggested, that in order to achieve that, scatterometry measurements would have to expand beyond the single angle spectroscopic ellipsometry (SE) to include data collected at multiple incidence angles, or sample orientations. We present results of sensitivity and precision estimates studies of periodic lines gratings at multiple incidence angles, different light wave-lengths, and different sample orientations relative to the ellipsometer incidence plane. We consider measurement sensitivity and precision not just for the critical dimensions, but also for the lines profile shapes (middle-, top-, bottom- CD's, top rounding), as well as resolving different elements of the composite spacer layers.