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Pouya Valizadeh
Professor of Electrical Engineering |
>Department of Electrical and Computer Engineering >Faculty of Engineering and Computer Science |
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The III-V electronic devices are of primary
research interest of our group. Wide band-gap semiconductor technologies in
general and III-Nitride heterostructure-based
devices in particular are the focus of our research. Design, fabrication and evaluation of these devices and
study of their power handling,
reliability and noise characteristics
constitute the group’s primary research activities. In
these studies, gauging the impacts of piezoelectricity on linearity, power
handling, reliability and noise of III-Nitride heterostructures are of our
interests. Developments
in wireless communications have drastically increased the need for
high-power, high efficiency, linear, low-cost, monolithic solid-state
amplifiers in the 1-30 GHz frequency range. While, mainstream III-V
technology (i.e., GaAs) fall short of satisfying a majority of these
requirements simultaneously, newer materials such as GaN, enjoying superior
electronic properties including wide bandgap, high peak and saturation
carrier velocity, large critical electric-field, huge polarization-based sheet
carrier concentration, and good thermal conductivity are deemed to have the
capacity to fulfill these requirements. Since the first demonstration of the
GaN HFET in mid-ninety’s, rapid progress has been made on the development of
these devices. Output power densities at microwave frequencies of GaN based
HFETs on both sapphire and SiC substrates have been significantly elevated to
values around 30 W/mm. As a result, the power amplifier market, currently
satisfied with a multitude of technologies, from silicon and III-V based
solutions to vacuum tubes, will be soon captured by the new rival: GaN. New projects are evolving in the group in the following
directions: 1. Microfabrication and viable strain relief
strategies for engineering the 2DEG of polar AlGaN/GaN and AlInN/GaN heterostructures (A. Loghmany,
B. AlOtaibi, J. Record, J.
Gosselin, K. Rahbardar, M. Aghayan, Y. Patel) 2. Microfabrication and modeling of quaternary
III-Nitride polar HFETs (F. Manouchehri,
K. Rahbardar, M. Aghayan,
Y. Patel, M. Omran) 3. Reliability-concerned device design in polar
AlGaN/GaN technology (F. Manouchehri, J. Sikder, M. Buitrago) 4. Modeling the tunneling behavior and gate
leakage in AlGaN/GaN heterostructures (K. Rahbardar,
J. Record, I. Singh, M. Aghayan) 5. Gate and drain low frequency noise
characterization and modeling of AlGaN/GaN and AlInN/GaN HFETs (F. Manouchehri,
Y. Patel) 6. Calculation of energy subbands in polar
III-Nitrides (F. Manouchehri, K. Rahbardar, M. Omran) 7. Wide bandgap power electronics for automotive
applications (S. Dargahi, M.
Buitrago) 8. Full analytical modeling of transport problem in AlGaN/GaN HFETs (A. Loghmany, M. Moradi, B. AlOtaibi, J. Sikder, I. Singh) 9. Switching and microwave circuit design in
E-/D-mode pair AlGaN/GaN technology 10. Integration of GaN electronics on Si (100) 11. MEMS-based CMOS-compatible high voltage electronics 12. Wide bandgap nano-wire resonators and resonating gate FETs |