2-D physical modeling and DC optimization of a double delta doped In0.7Ga0.3As/In0.52Al0.48As/InP pHEMT

This study focuses on the optimization of a fabricated double δ-delta doped In_0.7Ga_0.3As/In_0.52Al_0.48As/InP pHEMT using SILVACO TCAD. The first objective of this study is to develop a structure model from the fabricated device by inverse modeling to be able to match simulated results with measured results. The second objective is to suggest modifications in the geometry and the doping concentration of the barrier layer (or supply) in order to optimize the DC parameters of the pHEMT, such as max intrinsic transconductance and threshold voltage. The DC characteristics of the pHEMT structure present a good matching between with the measured data and the simulated results. We show that the maximum transconductance could be optimized by 50% and a linear relation between the doping concentration of barrier layer and the threshold voltage.