High-Electron-Mobility Transistors Based on InAlN/GaN Nanoribbons

作者：Azize Mohamed^*; Hsu Allen L; Saadat Omair I; Smith Matthew; Gao Xiang; Guo Shiping; Gradecak Silvija; Palacios Tomas

来源：IEEE Electron Device Letters, 2011, 32(12): 1680-1682.

DOI：10.1109/LED.2011.2170149

• Al(2)O(3) strain-passivation layer
• high-electron-mobility transistor (HEMT)
• InAlN/GaN nanoribbons (NRs)
• SiC substrate

We demonstrate high-electron-mobility transistors (HEMTs) based on InAlN/GaN nanoribbon (NR) structures. These devices, with NR widths d in the 50-90 nm range, are fabricated through a top-down technology on planar InAlN/GaN samples grown on a SiC substrate. The electrical properties of the InAlN/GaN NRs have been characterized by transmission-line model measurements and in HEMT structures, and compared with similar planar devices fabricated in close proximity. External mechanical stress and adequate surface passivation have a great impact on the NRs' performance. For example, when a thin Al(2)O(3) dielectric is used to passivate the surface and to introduce tensile stress in the NR devices, the sheet resistance in the NRs becomes up to similar to 46% lower than that in passivated planar structures. These enhanced transport properties resulted in NR HEMTs with similar to 20-45% higher raw current than that in planar HEMTs. The NR technology combined with strain-passivation engineering allows the fabrication of NR HEMTs with record current densities (similar to 2.9 A/mm) in the InAlN/GaN material system.

• 出版日期2011-12
• 单位MIT