Design and Simulation of Ge Pocket Vertical TFET Biosensor for Label Free Detection of Ovarian Cancer Biomarker HE4

This study highlights the use of a Ge Pocket VTFET biosensor to detect the ovarian cancer biomarker HE4 in serum. The device was optimized for increased sensitivity through simulations using the ATLAS TCAD tool. The device features four nanocavities carved under gates for the immobilization of biomarker HE4 serum, as well as a triple gate to improve gate control. The dielectric constant of the carved nanocavities changes as HE4 biomarkers are immobilized in them after replacing the prefilled air. This results in modulation of the device electrical characteristics. The stated biosensor's detection technique is heavily reliant on variations in the charge variation properties of HE4 histological subgroup. In a serum ecosystem, sensitivity analysis of the suggested model was conducted over a range of HE4 values among histological subgroups of ovarian cancer. The optimized biosensor exhibited ON-to-OFF current sensitivity of 1.62 ×10⁶ for the "Serous" histological subtype at a biomarker concentration of 386 pmol/L. The sensitivity of the Ge VTFET biosensor is measured in terms of VTH, ION, gm and SS. The biosensor has the highest sensitivity for serous type HE4 histological subgroup, with S_VTH = 0.5568, SI_ON = 4.46×106, Sgm = 1606, and SSS = 25.53. Furthermore, the suggested biosensor sensitivity is compared to that of existing biosensors, and it is found to be highly sensitive. The biosensor's error evaluation in terms of steric and repulsive hindrance is calculated as 16.93% which is better than state-of-the-art biosensors. As a result, the device can be used for array-based screening and diagnosis of ovarian cancer, with the advantage of being easier to fabricate and less expensive.