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), deposited on air-exposed Al, have been studied in situ as a function of temperature (similar to 200-300 K) using polarization-modulated infrared reflection 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 spectrum. At low temperature, in addition to damage, evidence is seen for a radiation-induced change in chain configuration leading to an increased interaction between ester groups and the Al surface. This configuration is unstable and is removed by annealing to similar to 300 K. [S0734-211X(99)01706-0].