Quantification of line-edge roughness of photoresists. I. A comparison between off-line and on-line analysis of top-down scanning electron microscopy images

An off-line image analysis algorithm and software is developed for the calculation of line-edge roughness (LER) of resist lines, and is successfully compared with the on-line LER measurements. The effect of several image-processing parameters affecting the fidelity of the off-line LER. measurement is examined. The parameters studied include the scanning electron microscopy magnification, the image pixel size dimension, the Gaussian noise-smoothing filter parameters, and the line-edge determination algorithm. The issues of adequate statistics and appropriate sampling frequency are also investigated. The advantages of off-line LER quantification and recommendations for the on-line measurement are discussed. Having introduced a robust algorithm for edge-detection in Paper I, Paper II [V. Constantoudis et al., J. Vac. Sci. Technol. B 21, 1019 (2003)] of this series introduces the appropriate parameters to fully quantify LER. (C) 2003 American Vacuum Society.