PROCEEDINGS ARTICLE | March 24, 2006
Proc. SPIE. 6152, Metrology, Inspection, and Process Control for Microlithography XX
KEYWORDS: Semiconductors, Spectrum analysis, Statistical analysis, Polarization, Photoresist materials, Software development, Line width roughness, Transistors, Critical dimension metrology, Edge roughness
Line edge and line width roughness (LER/LWR) is commonly estimated by standard deviation sigma. Since the
standard deviation is a function of sample line length L, the behavior of sigma(L) curve is characterized by the
correlation length and roughness exponent. In this paper, an efficient and practical macro LER/LWR analysis is
implemented by characterizing an arbitrary array of similar features within a single CD-SEM image. A large amount of
statistical data is saved from a single scan image. As a result, it reports full LER/LWR information including correlation
length, roughness exponent, sigma at infinite line length, and power spectrum. Off-line, in-house software is developed
for automated investigation, and it is successfully evaluated against various patterns. Starting with the detailed
description of the algorithm, experimental results are discussed.
