Transistores FET basados en Si y materiales 2d avanzados para tecnología super-Terahercios (PID2021-126483OB-I00)

This research proposal aims to develop advanced solid-state devices for applications in the terahertz (THz) region of the electromagnetic (EM) spectrum. The THz region (0.1-10THz) lies in the gap between microwaves and the far-infrared regions. The absence of practical technologies for generating and detecting EM radiation in the THz spectral region has coined the term “terahertz gap” to refer to the gap between THz and the technological maturity of the adjacent regions (infrared and microwaves). Across the past 25 years, motivated by the strikingly vast range of possible applications for THz radiation, many techniques have been investigated and demonstrated. This vast range of THz sensing applications includes astronomy, spectroscopy (various rotational, vibrational, and translational modes of light-weight molecules are within the THz range; since these modes are specific to a particular substance, it is possible to obtain a THz fingerprint), communications with a bandwidth significantly higher than those based on microwaves, security based both on imaging of concealed objects and spectroscopy, metrology, etc. The use of THz radiation – its diffraction-limited resolution is close to that of the human eye - in imaging is based in the unique properties of THz rays (T-rays): most common packaging materials such as cardboard and plastics are optically opaque, but transparent to T-rays allowing the detection of concealed objects. T-rays can also penetrate a few millimetres of skin, hence they can be used in the diagnostics of subcutaneous tissue, for instance, to detect skin cancer in vivo.This project will address the study, both experimental and numerically, and development of THz emission and THz direct signal sensing using several semiconductor technologies: based on Silicon advances transistors (FinFETs and strained-Si MODFETs) and based on 2d-materials FETs (Graphene FETs- GFETs, and FETs based on other system materials). All these FETs share the same physical mechanism to convert/obtain THz radiation: the interaction between THz EM radiation and the plasma of the two-dimensional electron gas (2DEG) above described. Those sensors share also the advantages of solid-state devices mentioned in the second paragraph above (low cost, small size, …), but each technology present specific properties and advantages, that will be studied both theoretical and experimentally in the present Project, that position them as very promising technologies for future commercial high-performance THz detectors.

Funding_entity: Ministerio de Ciencias e Innovación, Ref: PID2021-126483OB-I00

Period: 2022-2025

Principal investigator and Coordinator: Jesus Enrique Velázquez & Yahya Moubarak Meziani

Participants: Yahya M. Meziani, Enrique Velázquez, Jaime Calvo Gallego