Breast-Cancer Biomarker (C-erbB-2) Detection in Saliva/Serum Based on InGaAs/Si Heterojunction Dopingless TFET Biosensor

This research article reports the electrical detection of breast-cancer biomarker (C-erbB-2) in saliva/serum based on In1-xGaxAs/Si heterojunction dopingless tunnel FET (HJ-DL-TFET) biosensor for highly sensitive and real-time detection. The work takes into account the interface charge modulation effect in dopingless extended gate heterostructure TFET with embedded nanocavity biosensors for the precise, reliable, and fast detection of antigens present in the body fluids such as saliva in place of blood serum. The reported biosensor is numerically simulated in 2D using the SILVACO ATLAS exhaustive calibrated simulation framework. For the biomolecule immobilization, the proposed biosensor has a dual cavity engraved beneath the dual gate structure. This improves the control of biomolecules over the source-to-channel tunneling rate, as well as the control over the electrical performance parameters of the proposed biosensor. Here, a numerical model for the C-erbB-2 interface charge equivalent is also developed. The analysis of device sensitivity in both saliva and serum environments for various C-erbB-2 concentrations has been carried out. Our study reveals that III-V In1-xGaxAs/Si heterojunction with ${x}$ composition of 0.2 and extended gate geometry provides an increased tunneling probability, improves the gate control to get a higher ${I}_{\textit {ON}}/{I}_{\textit {OFF}}$ ratio and higher sensitivity. In addition to this, the impact of interface charges corresponding to the different amounts of C-erbB-2 biomarkers on the biosensor sensitivity (in terms of ${I}_{\textit {ON}}/{I}_{\textit {OFF}}$ ratio) yields higher sensitivity of the order of ${10}^{{6}}$ .