Gate-length and Donor-layer Characteristics Optimization of InAlAs/InGaAs DG-HEMT for Improved RF and Noise Performance

The paper focuses on the significance of optimization of the various device parameters for achieving improved RF and noise performance. A charge control based analytical model is employed for the evaluation of various performance parameters of InAlAs/InGaAs double-gate (DG-) HEMT. While, shortening of gatelength leads to significant improvement in the device performance in terms of lower Minimum Noise Figure (NF_min) and higher Maximum Frequency of Oscillation (f_max), reduction in the donor-layer thickness leads to lower f_max. In addition to this, increase in the donor-layer doping which accompanies reduction in gatelength and donor-layer thickness leads to lower f_max and higher NF_min. Therefore, optimisation of various device parameters is essential for achieving improved RF and noise performance without letting the short channel effects become dominant.