Investigation of DC and RF Performance of Novel MOSHEMT on Silicon Substrate for Future Submillimetre Wave Applications

Abstract

In this work, the DC and RF performance of a 20 nm gate length novel metal oxide semiconductor high electron mobility transistor (MOSHEMT) on Silicon substrate is studied using Sentaurus TCAD tool. The proposed MOSHEMT device features a novel T-gate structure, heavily doped In0.52Ga0.48As source/drain regions, delta doped planes on both sides of the In0.75Ga0.25As/InAs/In0.75Ga0.25As composite channel, a multi layer cap and a very thin layer of HfO2 as gate dielectric. The TCAD simulation results obtained at room temperature using hydrodynamic carrier transport model indicates that the 20 nm gate length proposed MOSHEMT device is capable of providing a peak drain current of 2450 mA/mm at VDS = 0.6 V and the peak transconductance obtained for the proposed device is 2900 mS/mm. The fT and fmax obtained for the Lg = 20 nm proposed MOSHEMT on Silicon substrate are 372 and 480 GHz respectively. At 300 K, the measured Hall mobility of the electrons in the quantum well channel is 9600 cm2/(V s). The on state resistance (RON) obtained for the Lg = 20 nm proposed device is 116 Ohm μm. These devices are undoubtedly, the most suitable candidates for future sub millimetre wave applications.