Advanced scanning electron and atomic force microscopy technique have been developed to quantify line-edge and sidewall roughness in patterned resist and silicon feature with nanometer scale accuracy. Both techniques are able to follow small changes in the line-edge roughness. The measurement repeatability of the scanning electron and atomic force microscope was characterized and is 0.1 and 0.6 nm, respectively. Any roughness measured in the single layer resist mask transfers to the underlying silicon throughout a range of pattern transfer conditions. Within the measurement precision, silicon pattern transfer does not appear to decrease or increase the sidewall or line-edge roughness. An attempt to quantify the edge-roughness spatial frequency is discussed. The scanning electron microscope is still recommended over the atomic force microscope for line-edge roughness measurements based on sample throughput.

Date Published: 14 June 1999
PDF: 9 pages
Proc. SPIE 3677, Metrology, Inspection, and Process Control for Microlithography XIII, (14 June 1999); doi: 10.1117/12.350860

Published in SPIE Proceedings Vol. 3677:
Metrology, Inspection, and Process Control for Microlithography XIII
Bhanwar Singh, Editor(s)