In this book chapter the authors have discussed the physical mechanisms explaining THz detection in FETs. Such detectors can support two modes of operations: (i) resonant mode and (ii) nonresonant mode. Even though resonant photo-detection is still to be fully demonstrated at room temperature, a lot of work has been done on nonresonant photo-detection using FETs. In this regard, nanometer size FETs operating as broadband THz detectors currently compete and are suitable alternatives to commercially available Schottky diodes. Recent studies show that FETs can reach responsivity levels, NEP, and speed of the same order of magnitude as Schottky diodes while having advantages arising from CMOS VLSI compatibility. In this regard, we have also presented an overview of recent experimental results on the detection of THz radiation by nanowire and GFETs.

Chapter Contents:

• 7.1 Principles of THz detection in FETs
• 7.1.1 Dyakonov-Shur model
• 7.1.2 Theoretical formalism and modes of operation
• 7.1.3 Nonresonant detection: principles and advantages of subthreshold biasing
• 7.2 Overview of THz detectors and state of the art
• 7.2.1 Recent progress on nanowire-based THz detectors
• 7.2.2 Recent progress on graphene-based THz detectors
• 7.3 Emerging FET devices for THz detection applications: dual independent gate FinFET with super-steep subthreshold slope
• 7.3.1 A continuous compact DC model
• 7.3.2 Noise-equivalent power predictions
• 7.4 Conclusions
• References

Inspec keywords: reviews; field effect transistors; nanoelectronics; terahertz wave detectors

Other keywords: nonresonant photo-detection; resonant photo-detection; nonresonant mode; resonant mode; super sensitive terahertz detectors; THz detection; broadband THz detectors; responsivity levels; nanometersize FETs; room temperature; nanowire FETs; overview

Subjects: Sensing devices and transducers; Microwave measurement techniques; Nanometre-scale semiconductor fabrication technology; Other field effect devices