Effects of ultraviolet (UV) light irradiation on polymer dry etching processes have been investigated with the use of a low-energy mass-selected ion beam injection system. Etching yields of poly(methyl methacrylate) (PMMA) by Ar or CF3 ion beam injections were evaluated from the loss of PMMA film weight measured by a quartz crystal microbalance (QCM) during the ion beam injection process with or without simultaneous UV light irradiation. Significant enhancement of the etching yield of PMMA was observed during the simultaneous irradiation with CF3 ion beam and UV light over the sum of its sputtering yields obtained from separate ion-beam or UV-light injection processes. By contrast, no significant change of etching yields was observed when the UV light was superposed on the Ar ion beam.
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