Investigation of radiation sensitivities of methacryl acid methylester-methacryl acid copolymers

An increase in the lithographic radiation sensitivity upon thermal treatment is demonstrated for poly(methyl methacrylate/methacrylic acid) co-polymers. The preferable cleavage of side chain carboxyl groups during the radicalic degradation follows from electron paramagnetic resonance and radiothermoluminescence investigations. The increase in lithographic sensitivity due to the thermal treatment can be explained by a nonradicalic scission of anhydride groups. (author)