Top-down fabrication of AlGaN/GaN nanoribbons

Abstract

Lateral AlGaN/GaN nanoribbons (NRs) have been fabricated through a top-down technology on planar AlGaN/GaN samples grown on a silicon substrate. Electron-beam lithography and Cl2-based dry etching were used to define the NRs with widths in the 70–145 nm range. The electrical and structural properties of the AlGaN/GaN NRs have been measured and compared to standard planar structures fabricated on the same chip. External mechanical stress and adequate surface passivation have an important effect on the NR’s performance. A 50% improvement in the current density of SixNy passivated AlGaN/GaN NRs was obtained with respect to planar samples.