Share Email Print

Proceedings Paper

Plasmonic response of partially gated field effect transistors
Author(s): S. Rudin; G. Rupper; M. L. Reed; M. Shur
Format Member Price Non-Member Price
PDF $17.00 $21.00

Paper Abstract

Electron density oscillations in the transistor channels - plasma waves in the two-dimensional electron gas - determine the high frequency device response. Plasmonic field effect transistors have emerged as very sensitive, tunable, and extremely fast detectors of THz radiation. They have been implemented using silicon (CMOS), AlGaAs/InGaAs HEMTs, and AlGaAs/InGaAs HEMTs, with the HEMTs shown to operate more efficiently at higher THz frequencies. These HEMTs have both gated and ungated sections of the device channel between the source and drain, and the photovoltaic regime of operation requires an asymmetric gate placement in the device channel. The interactions of the plasma waves in the gated and ungated channel regions strongly affect the overall response and have been investigated in numerous publications. This work addresses a new aspect of such interaction - the effect of the relative position of the gated and ungated section. We show this previously unexplored effect plays a dominant role in determining the response. The results of the numerical simulation based on the solution of the complete system of the hydrodynamic equations describing the electron fluid in the device channel show that the inverse response frequency could be approximated by the sum of the gated plasmon transit time in the gated section of the device, the ungated plasmon transit time in the ungated section of the device between the gate and the drain, and the RC gate-to-source constant. Here R and C are the resistance and capacitance of the gate to source section. Hence, the highest speed is achieved when the gate is as close to the source as possible. This suggests a novel plasmonic detector design, where the gate and source electrode overlap, which is shown to have a superior frequency response for the same distance between the source and the drain.

Paper Details

Date Published: 26 September 2016
PDF: 5 pages
Proc. SPIE 9934, Terahertz Emitters, Receivers, and Applications VII, 99340I (26 September 2016); doi: 10.1117/12.2238036
Show Author Affiliations
S. Rudin, U.S. Army Research Lab. (United States)
G. Rupper, U.S. Army Research Lab. (United States)
M. L. Reed, U.S. Army Research Lab. (United States)
M. Shur, Rensselaer Polytechnic Institute (United States)

Published in SPIE Proceedings Vol. 9934:
Terahertz Emitters, Receivers, and Applications VII
Manijeh Razeghi; Alexei N. Baranov; John M. Zavada; Dimitris Pavlidis, Editor(s)

© SPIE. Terms of Use
Back to Top
Sign in to read the full article
Create a free SPIE account to get access to
premium articles and original research
Forgot your username?