Design of Dopingless GaN Nanowire FET with Low ‘Q’ for High Switching and RF Applications

Abstract

The unique properties like wide band gap and high electron mobility makes GaN an interesting material to be used in building devices at the nanoscale in recent times. This paper first time proposed a charge plasma (CP) based dopingless gate all around (GAA) GaN Nanowire FET (NWFET) (CP-GaN). The advantages of CP device over junctionless (JL) in NWFET structure along with properties of GaN material, results in a highly efficient structure of CP-GaN. The CP-GaN is compared with JL-GaN and silicon counterparts of CP & JL. Results reveal that CP-GaN is showing outstanding performance as Ion of 3.95 × 10−5 A, Ioff of 5.36 × 10−13 A and Ion/Ioff of 7.37 × 107. The proposed device CP-GaN shows better performance than CP-Si based device. When compared with JL-GaN, CP-GaN shows 55% less DIBL. The figure of merit Q = gm/SS of 0.85 μS/μm-dec/mV, is highest for our proposed CP-GaN. This makes CP-GaN an attractive design to be explored for high switching & low voltage applications with reduced SCEs and lower thermal budget. The other design parameters viz. gate length, gate dielectric, gate and source/drain work functions, nanowire radius and interface trap charges effect are also investigated for further optimization of the proposed design.