Novel Label-Free Detection of Cancer Biomarkers Using T-Shape Channel and L-Shape Nano-Cavity in Si:HfO2 Ferroelectric DM-JLTFET with Gate Staggering Biosensor

This paper presents a novel label-free biosensing method for the detection of cancer biomarkers using a T-shape channel and L-shape nano-cavity in a Si:HfO₂ based ferroelectric Dielectrically modulated Junctionless Tunnel Field Effect Transistor (FE DM-JLTFET). The biosensor exploits the modulation of energy band alignment in the Si:HfO₂ heterostructure due to the immobilization of cancer biomarkers with different dielectric properties within precisely etched nano-cavities. For the first time, various cancer cell lines such as Colorectal cancer (SW 620 at 0.5 THz), Kidney cancer (HEK293 at 0.5 THz) and osteosarcoma (SaOS-2 at 1 GHz, 143B at 1 GHz) have been separated based on their unique dielectric constants at specific frequencies so that healthy and cancer-infected cells can be distinguished. The immobilized biomolecules change the local electric field distribution leading to a change in the energy bands and consequently the control of the tunneling current. The proposed FE DM-JLTFET operates at a frequency of 2.4 GHz. The modulation of the device tunneling current and I_ON/I_OFF ratio depends directly on the dielectric constant of the immobilized biomolecules. This shifting in the energy band structure enables highly sensitive and specific detection of nanoscale dielectric variations. By comparing the responses of affected and healthy cells this proposed device is able to show strong biomarker identification capabilities. With gate-staggering the carrier tunneling through the changed energy bands is improved further amplifying detection efficiency. This biosensor can be used as a point-of-care diagnostic tool offering low-cost, rapid and scalable detection for early diagnosis of colorectal cancer (SW 620), kidney cancer (HEK 293) and osteosarcoma (SaOS-2, 143B) outperforms traditional diagnostic methods.