Novel Metamorphic HEMTs With Highly Doped InGaAs Source/Drain Regions for High Frequency Applications

In this paper, we report the first result of a strained In_0.52Ga_0.48 As channel high-electron mobility transistor (HEMT) featuring highly doped In_0.4Ga_0.6 As source/drain (S/D) regions. A lattice mismatch of 0.9% between In_0.52Ga_0.48 As and In_0.52Ga_0.48 As S/D has resulted in a lateral strain in the In_0.52Ga_0.48 As channel region, where the series resistance is reduced with highly doped S/D regions. An experimentally validated device simulation is advanced for the proposed HEMT, and the results of this paper have shown that there are 60% drive-current and 100% transconductance improvements, compared with the conventional structure. A remarkable 150-GHz increase in the cutoff frequency has been seen for the proposed structure over the conventional one as well for the shown devices.