A novel gate-staggered ferroelectric DM-JLTFET biosensor with T-channel and L-cavity for label-free cancer biomarker detection

This work presents a new label-free biosensing technique for detecting Cancer biomarkers in a Ferroelectric Dielectrically Modulated Junction less Tunnel Field-Effect Transistor (FE DM-JLTFET) based on Si: HfO₂ that uses an L-shaped nano-cavity and a T-shaped channel. When cancer biomarkers with varying dielectric properties are immobilized within the nanocavities, they alter the local permittivity, which affects the electric field distribution in the Si: HfO₂ heterostructure. This change influences the energy band profile and modulates the band-to-band tunneling (BTBT) current utilized for biosensing. The proposed device operates at 2.4 GHz and shows different current responses to different cancer cell lines based on their frequency-dependent permittivity profiles such as Colorectal Cancer (SW 620, K = 3.9 at 0.5 THz), Kidney Cancer (HEK293, K = 4.0 at 0.5 THz), Brain Cancer (U-87 MG, K = 20 at 1.2 GHz, Breast Cancer (MDA-MB-231, K = 22 at 2 GHz) and Osteosarcoma (SaOS-2 (K = 45) 143B (K = 50) at 1 GHz). For the first time, frequency-selective dielectric modulation is used to reliably discriminate between many cancer categories using a single nanoscale transistor sensor. High sensitivity and specificity in detection are made possible by the direct control of the Ion/Ioff ratio by the induced changes in energy bands. Additionally, by increasing tunneling efficiency, gate-staggering amplifies current modulation for better diagnostic resolution. With its ability to identify Colorectal, Kidney, Breast, Brain, and Bone Cancers early and accurately this small affordable and scalable biosensor platform shows great promise for real-time, point-of-care cancer diagnostics.