Topographical patterns were fabricated with speeds >103 features per second into poly(methylmethacrylate) (PMMA) films with a Ga+ focused ion beam. This material removal rate is orders of magnitude greater than expected in conventional sputtering. The relevant ion-beam sputtering parameters have been investigated to explore the mechanism of the extraordinary materials removal rate. It is speculated that structural changes during ion bombardment, specifically a beam-enhanced unzipping reaction of the PMMA chains, play an important role for the high material removal rate. These high throughput PMMA topographic patterns can be used as masters for high-resolution elastomer molding and microcontact printing.

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