Sensitivity Analysis of Al0.3Ga0.7N/GaN Dielectric Modulated MOSHEMT Biosensor

Abstract

Emerging and newly proposed devices integrate various materials at different scales (from nano to submicron), which reveals sensor response. Prefab simulation is in great demand to elucidate fundamental biosensor phenomena that are based on transistors. Numerous HEMT-based biosensors have been developed, however, MOSHEMT deserves to be further investigated. The sensitivity analysis with neutral and charged biomolecules is thus carried out in this research using a single gate high-κ dielectric MOSHEMT through Technology Computer Aided Design simulation. The device performance is evaluated through the shift (sensing action) of device parameters like Two-Dimensional Electron Gas, on-current, transconductance, drain current and output conductance due to the immobilization of biomolecules in the cavity created under the gate. For the neutral biomolecule ( κ = 8 ), the fluctuation in on-current, transconductance, drain current, and output conductance is determined to be 330.3 μA μm−1, 102.0 μS μm−1, 319.0 μA μm−1, and 534.9 μS μm−1, respectively. Positively charged biomolecules were more sensitive to the device than negatively charged ones. Analysis is done on the response to the fill rates of the biomolecules in the cavity. For the vertical, horizontal, and tapered profiles, the transconductance sensitivities are 0.65, 0.17, and 0.32 and the drain current sensitivities are 0.25, 0.16, and 0.27 at the lowest fill (25%). In light of this, the AlGaN/GaN dielectric modulated MOSHEMT assures that the device can be used in sensitive intelligent biomedical applications.