A Comprehensive Review on Tunnel Field-Effect Transistor (TFET) Based Biosensors: Recent Advances and Future Prospects on Device Structure and Sensitivity

Topological quantum devices: a review

The introduction of the concept of topology into condensed matter physics has greatly deepened our fundamental understanding of transport properties of electrons as well as all other forms of quasi particles in solid materials. It has also fostered a paradigm shift from conventional electronic/optoelectronic devices to novel quantum devices based on topology-enabled quantum device functionalities that transfer energy and information with unprecedented precision, robustness, and efficiency. In this article, the recent research progress in topological quantum devices is reviewed. We first outline the topological spintronic devices underlined by the spin-momentum locking property of topology. We then highlight the topological electronic devices based on quantized electron and dissipationless spin conductivity protected by topology. Finally, we discuss quantum optoelectronic devices with topology-redefined photoexcitation and emission. The field of topological quantum devices is only in its infancy, we envision many significant advances in the near future.

Study on the Simulation of Biosensors Based on Stacked Source Trench Gate TFET

In order to detect biomolecules, a biosensor based on a dielectric-modulated stacked source trench gate tunnel field effect transistor (DM-SSTGTFET) is proposed. The stacked source structure can simultaneously make the on-state current higher and the off-state current lower. The trench gate structure will increase the tunneling area and tunneling probability. Technology computer-aided design (TCAD) is used for the sensitivity study of the proposed structured biosensor. The results show that the current sensitivity of the DM-SSTGTFET biosensor can be as high as 10⁸, the threshold voltage sensitivity can reach 0.46 V and the subthreshold swing sensitivity can reach 0.8. As a result of its high sensitivity and low power consumption, the proposed biosensor has highly promising prospects.

Self-connected CuO-ZnO radial core-shell heterojunction nanowire arrays grown on interdigitated electrodes for visible-light photodetectors

An original photodetector system based on self-connected CuO–ZnO radial core–shell heterojunction nanowire arrays grown on metallic interdigitated electrodes, operating as visible-light photodetector was developed by combining simple preparation approaches. Metallic interdigitated electrodes were fabricated on Si/SiO₂ substrates using a conventional photolithography process. Subsequently, a Cu layer was electrodeposited on top of the metallic interdigitated electrodes. The CuO nanowire arrays (core) were obtained by thermal oxidation in air of the Cu layer. Afterwards, a ZnO thin film (shell) was deposited by RF magnetron sputtering covering the surface of the CuO nanowires. The morphological, structural, compositional, optical, electrical and photoelectrical properties of the CuO nanowire arrays and CuO–ZnO core–shell nanowire arrays grown on metallic interdigitated electrodes were investigated. The performances of the devices were evaluated by assessing the figures of merit of the photodetectors based on self-connected CuO–ZnO core–shell heterojunction nanowire arrays grown on the metallic interdigitated electrodes. The radial p–n heterojunction formed between CuO and ZnO generates a type II band alignment that favors an efficient charge separation of photogenerated electron–hole pairs at the CuO–ZnO interface, suppressing their recombination and consequently enhancing the photoresponse and the photoresponsivity of the photodetectors. The electrical connections in the fabricated photodetector devices are made without any additional complex and time-consuming lithographic step through a self-connecting approach for CuO–ZnO core–shell heterojunction nanowire arrays grown directly onto the Ti/Pt metallic interdigitated electrodes. Therefore, the present study provides an accessible path for employing low dimensional complex structures in functional optoelectronic devices such as photodetectors.

Recent Study on Schottky Tunnel Field Effect Transistor for Biosensing Applications

In this review, we discussed highly sensitive biosensor devices which is having a more attractive, wide scope and development in the sensing field. Biosensor devices can detect the charged and neutral charged biomolecules such as protein, nucleic acids, antibody agents and viruses. Due to these highly sensitive biosensor devices, we mainly focused on schottky tunnel field-effect transistors (STFET), these transistors have unique properties such as enhanced transconductance and gate controllability, low leakage current etc. In addition, we studied the performances and challenges of STFET by dielectric modulation doping concentration, dielectric modulation, and heterostructure devices. Further, we have reviewed the comparison of STFET and conventional devices. This article reviews mainly on the study of high sensitivity analysis of STFET and modified Schottky-TFET structures for the use of biosensing applications.

Nanowire gate all around-TFET-based biosensor by considering ambipolar transport

This work investigated the performance of overlapped gate-on-drain of a gate all around-tunnel field-effect transistor (GAA-TFET) biosensors by considering the dielectric modulated technique by immobilizing the targeted biomolecules in the cavity region curved under the overlapped gate-on-drain. The nanowire GAA-TFET device shows excellent controllability over the channel and reduces leakage current to a greater extent. Here, we tried to make the ambipolar nature of the TFET, an advantage for the biosensor by detecting the biomolecule using variation of ambipolar current of TFET. Due to structural arrangement, the nanocavity under the overlapped gate region suppresses the ambipolar drain current by increasing the dielectric constant of the targeted biomolecules. The device can show a variation of 10² and 10³ amount of sensitivity for the variation of dielectric constant from 1 to 5 and, compared with the other TFET structure, the proposed overlapped gate-on-drain GAA-TFET biosensor shows higher sensitivity and low leakage with a highly controlled channel.