Theoretical study of polymer resists direct etching, accompanied by polymer matrix movement

Model of direct etching of polymer resists under the influence of ion beams is constructed. Theory is based on the diffusion mechanism of the loss out of low-molecular-mass fragments and free volumes, created under the influence of radiation within polymer. Differ from previous theory proposed the model takes into account movement of matrix and irradiated surface of polymer films, which is caused by diffusion of fragments and free volumes out film. Consideration of this movement is of importance during lardge doses irradiation, then change of polymer's thickness and composition are significant. The results of model agree well with the experimental data for etching under light ion irradiation of PMMA (PolyMethylMethAcrylate). Proposed theory is of great practical interest in connection with fine-pattern fabrication in microelectronics.