The effect of line edge roughness(LER)is an increasingly important problem as lithographic feature dimensions shrink to the sub-100 nm level.Previous experiments have demonstrated several key material properties that influence LER,such as incompatibility between protected and deprotected components [1],casting solvents,base additives and photoacid generators [2],as well as process conditions such as X-ray or UV dosage to mask and post-exposure bake protocols [3].
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