Image Based Metrology for Quantitative Analysis of Local Structural Similarity of Nanostructures

The orientation correlation function is a measure of the spatial range over which nanoscale structures maintain their structural (orientational) similarity. In this paper we describe an image processing system that is used to estimate this correlation function from electron microscope images of the chemically patterned nanoscale structures. We describe the estimation of a robust orientation field from the image and the subsequent estimation of the correlation function from the orientation field. We present results that have been obtained using our image metrology system. Sensitivity of the estimated values with respect to the image processing parameters is also presented.