Jesús Enrique Velázquez-Pérez

University of Salamanca

Jesús Enrique Velázquez-Pérez obtained his Ph.D. from the Universidad de Salamanca (USAL), Spain, and the Institute of Fundamental Electronics, University of ParisXI, Orsay, France, in 1990 with his work on the simulation of high-speed devices using models based on the Monte Carlo (MC) technique. In 1990, he joined the faculty of USAL as a Professor of Electronics. At that time, his research focused on Radiofrequency and noise modeling of heterojunction bipolar transistors (HBTs). From 1998 to 2004, he was an invited researcher at the Imperial College London, UK, developing n-channel Si/SiGe MODFETs technology for low-power RF and millimeter-wave applications. This work led to strained-Si MODFETs and, later, to graphene field-effect transistor (FET) plasma-wave-based THz detectors. He has coauthored about 100 papers and more than 150 communications to international conferences.

2chapters authored

Chapters authored

Detection of Terahertz Radiation from Submicron Plasma Waves Transistors

By Y. M. Meziani, E. Garcia, J. Calvo, E. Diez, E. Velazquez, K. Fobelets and W. Knap

Part of the book: Bolometers

Room-Temperature Terahertz Detection and Imaging by Using Strained-Silicon MODFETs

By Juan Antonio Delgado-Notario, Vito Clericò, Kristel Fobelets, Jesús Enrique Velázquez-Pérez and Yahya Moubarak Meziani

This chapter reports on an experimental and theoretical study of Schottky-gated strained-Si modulation-doped field-effect transistors (MODFETs) with different sub-micron gate lengths (100, 250, and 500 nm). Room-temperature detection of terahertz (THz) radiation by the strained-Si MODFETs was performed at two frequencies (0.15 and 0.3 THz). A technology computer-aided design (TCAD) analysis based on a two-dimensional hydrodynamic model (HDM) was used to investigate the transistor response to THz radiation excitation. TCAD simulation was validated through comparison with DC and low-frequency AC measurements. It was found that the photoresponse of the transistors can be improved by applying a constant drain-to-source bias. This enhancement was observed both theoretically and experimentally. The HDM model satisfactorily describes the experimental dependence of the photoresponse on the excitation frequency, the gate bias, and the drain-to-source current bias. The coupling of the incoming THz radiation to the MODFETs was studied at 0.15 and 0.3 THz. Finally, to demonstrate the suitability of strained-Si MODFET for terahertz applications, an image sensor within a pixel-by-pixel terahertz imaging system for the inspection of hidden objects was used.

Part of the book: Design, Simulation and Construction of Field Effect Transistors

Jesús Enrique Velázquez-Pérez

Chapters authored

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