Sub-100 nm device fabrication rules require extremely tight control of line-edge roughness (LER) of patterned structures. During lithographic processes the resist film introduces an initial LER due to its chemical structure and processing. This initial LER evolves during the subsequent processing steps. In order to reduce LER the relation between polymer chain geometrical characteristics and finally measured LER has to be determined. Following this approach three model polymer chain architectures were considered and their LER was determined. A direct relation is seen between the measured LER and the excluded volume constraints on the polymer chain.