Abstract
Plasma waves in gated 2-D systems can be used to efficiently detect THz electromagnetic radiation. Solid-state plasma wave-based sensors can be used as detectors in THz imaging systems. An experimental study of the sub-THz response of II-gate strained-Si Schottky-gated MODFETs (Modulation-doped Field-Effect Transistor) was performed. The response of the strained-Si MODFET has been characterized at two frequencies: 150 and 300 GHz: The DC drain-to-source voltage transducing the THz radiation (photovoltaic mode) of 250-nm gate length transistors exhibited a non-resonant response that agrees with theoretical models and physics-based simulations of the electrical response of the transistor. When imposing a weak source-to-drain current of 5 μA, a substantial increase of the photoresponse was found. This increase is translated into an enhancement of the responsivity by one order of magnitude as compared to the photovoltaic mode, while the NEP (Noise Equivalent Power) is reduced in the subthreshold region. Strained-Si MODFETs demonstrated an excellent performance as detectors in THz imaging.
Highlights
The terahertz (THz) region lies in the gap between microwaves and infrared regions of the electromagnetic (EM) spectrum
THz range; since these modes are specific to a particular substance, it is possible to obtain a THz fingerprint) [4,5,6], communications with a bandwidth significantly higher than those based on microwaves [7], security based both on imaging of concealed objects and spectroscopy [9], metrology [10], etc
Solid-state plasma wave-based sensors can be used in THz imaging systems
Summary
The terahertz (THz) region lies in the gap between microwaves and infrared regions of the electromagnetic (EM) spectrum. Across the past 25 years, motivated by the strikingly vast range of possible applications for THz radiation, many new terahertz techniques have been investigated and demonstrated [1] This vast range of THz sensing applications includes astronomy [2,3], 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) [4,5,6], communications with a bandwidth significantly higher than those based on microwaves [7] (detection of high data rate wireless communication has been demonstrated [8]), security based both on imaging of concealed objects and spectroscopy [9], metrology [10], etc. Solid-state semiconductor devices allow the development of low-cost, compact, and reliable systems; the extension of their operation frequency range is of great interest to implement THz sources and detectors
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
