Graphene-Based Asymmetric Triple Material Surrounding Gate TFET for Ultrasensitive Detection of Plasmodium Falciparum Rhoptry Proteins

An Asymmetric Source and Drain Triple Material Surrounding Gate Graphene Tunnel Field-Effect Transistor (ASD-TM-SG-GTFET) is designed for ultrasensitive detection of Plasmodium falciparum rhoptry proteins, critical biomarkers for malaria diagnosis. Leveraging graphene’s high carrier mobility and a triple material gate (platinum, titanium, aluminum) with asymmetrical doping, the device enhances channel-to-substrate current control, reduces band-to-band tunneling, and achieves a steep subthreshold swing (2.25mV). Nanocavities in a high-k dielectric stack ( HfO 2 / SiO 2 ) enable label-free biomolecular sensing by modulating tunneling current, with high sensitivity to rhoptry proteins (k=80). Analytical models using 2D Poisson Equations. and finite difference techniques align with TCAD simulations, predicting surface potential, electric field, and drain current. Compared to traditional TFETs, the ASD-TM-SG-GTFET offers improved Transconductance and sensitivity due to its graphene channel and gate design, with a high ON/OFF current ratio (1.8 × 10 12 ) and subthreshold swing sensitivity (0.64 mV/decade) analyzed for various cavity lengths,cavity fill factor and cavity thickness values. The Proposed work is evaluated with various dielectric constant values like SARS-CoV,Zika,H1N1 Influenza and Results are compared with rhoptry protein value.This work also enables detection of low-concentration bio molecules in dense samples like serum, promising rapid malaria diagnosis and future integration with microfluidics for personalized medicine.