Enhanced quantitative analysis of resist image contrast upon line- edge roughness (LER)

Abstract

Correlations between LER and various types of aerial image contrast were examined for three different commercial resists. LER was more tightly correlated with the standard (max-min) definition of contrast than with the others examined, suggesting that background flare is most accountable for aerial image profile-induced LER. The relationship was nearly inverse, with LER proportional to α (contrast)^-0.85. In the latter portion of this paper, an image deblurring technique to recover more accurate LER data from SEM images was devised. This technique showed that, at times, LER can vary significantly before and after deblurring. Some initial tests to prove the validity of this LER measurement enhancement technique were performed, all with positive results.