Root-cause decomposition of line edge roughness and its application to cross-section profile prediction using top-view SEM images

Abstract

Quantification of line-edge roughness of photoresists. I. A comparison between off-line and on-line analysis of top-down scanning electron microscopy imagesThe line-edge roughness obtained from top-view scanning electron microscope (SEM) images is decomposed into three components; parallel shift, cross-sectional shape deformation, and surface roughness. The local slope angle of the pattern surface is estimated from the surface roughness component, which corresponds to the projection of the surface roughness onto the substrate plain. Cross-sectional profiles reconstructed by scanning this procedure across top-view SEM images show good agreement with the results obtained by other metrology methods, such as atomic force microscopy.