Impact of doping concentration and donor-layer thickness on the dc characterization of symmetric double-gate and single-gate InAlAs/InGaAs/InP HEMT for nanometer gate dimension-A comparison

The aim of this paper is to investigate the impact of gate-length (L
_g
) and doping concentration (N
_d
) of the donor layer and its thickness (d
_a
) on the performance of double-gate (DG) InAlAs/InGaAs/InP HEMT. A comparison of the impact of donor-layer doping concentration, donor-layer thickness and gate-length on the channel current, transconductance, gate-to-source capacitance and cut-off frequency for the DG-HEMT has been studied with that for SG-HEMT. As a result of this comparison the DG-HEMT has been seen to exhibit more sensitivity to these device parameters. This is due to greater sheet-carrier concentration and better gate-control. Thus, the optimization of the donor-layer doping, donor-layer thickness and gate-length in the case of DG-HEMT is crucial.