Low-energy electron-beam effects on poly(methyl methacrylate) resist films

The effects of low-energy electron irradiation (10-50 eV, up to similar to 2 x 10(17) e cm(-2)) on thin films of poly(methyl methacrylate) (PMMA), dep osited on air-exposed Al, have been studied in situ as a function of temper ature (similar to 200-300 K) using polarization-modulated infrared reflecti on absorption spectroscopy. Near 300 K damage is seen in the form of a loss of material, as shown by a decrease in the intensity of the entire PMMA sp ectrum. At low temperature, in addition to damage, evidence is seen for a r adiation-induced change in chain configuration leading to an increased inte raction between ester groups and the Al surface. This configuration is unst able and is removed by annealing to similar to 300 K. [S0734-211X(99)01706- 0].