Polycarbonate as a negative-tone resist for electron-beam lithography

Polycarbonate has excellent mechanical properties, and previous studies have demonstrated the use of polycarbonate as a positive-tone resist for electron-beam lithography (EBL). The current study demonstrates that polycarbonate can also behave as a negative-tone resist under a very high electron exposure dosage. The negative-tone behavior is investigated in detail through EBL and thickness measurements. The change in the chemical structure of polycarbonate due to electron exposure is also studied by Raman spectroscopy. The negative-tone behavior and the effective dosage variation on a patterned substrate can potentially be exploited to develop a new electron-beam patterning technique. This technique can replicate polymer patterns by flood electron exposure of a polycarbonate layer on top of a prepatterned metallic template. (C) 2018 Author(s).