In this research work, design of the extended field plate length (E-FPL) t-gate with Fe-doped AlGaN buffer structure on the graded aluminum gallium nitride (AlGaN)/ gallium nitride (GaN) high electron mobility transistor (HEMT) is proposed. The gate length of 60 nm with an ExFPL up to 50 nm towards the drain shows remarkable improvement in breakdown voltage. Meanwhile, the drain current and transconductance is further improved by the Fe-doped AlGaN Buffer design. In radio frequency (RF) small signal analysis this device exhibits a peak current-gain cutoff frequency fT of 148 GHz. This device has improved transconductance of 24% with high frequency. It is highly compatible with military applications such as RF upstream transmitters, ship and aircraft communication transmitters and high-frequency radars (HFRs).

The health sector, focusing on the wellness of society, is advancing in the phases of diagnosis and treatment. Biosensor-based devices are used to diagnose a variety of human diseases. Recently, there was a sudden hike in the human mortality rate by chronic diseases caused by mutants of SARS-COV-2, on a global scale. It is important to detect these kinds of diseases at an early stage to reduce the risk of spreading. For the analysis of Covid – 19 influenza, tests such as rapid antigen tests, True NAT, CBNAAT, and the commonly done RPT PCR were utilized. This proposal describes a non-invasive, quick, and practical method for sensing at-risk or infected persons with SARS-COV-2, aiming at controlling the epidemic. The proposed method employs a breath sensing device consisting of a graphene field effect transistor biosensor which can identify disease-specific biomarkers in exhaled breath, hence allowing speedy and precise detection. This test aids screening of large populations as it is simple and quick and emerges as a promising candidate for SARS-COV-2 tests due to a high sensitivity. This work justifies the accurate diagnosis of Severe Acute Respiratory Syndrome COV 2 from aerosol particles by GFET Biosensor.