CMOS Terahertz and mm-Wave Electronics: Reaching the Fundamental Limits
Monday, May 23, 1003 Kemper Hall, 11:00am-12:00pm
Speaker: Omeed Momeni
Host: Professor Rick Kiehl
There is a growing interest in terahertz and mm-wave systems for compact, low cost and energy efficient imaging and spectroscopy. Detection of concealed weapons, cancer diagnosis, food quality control, and breath analyses for disease diagnosis are among many examples that will rapidly flourish if compact and on-chip terahertz systems are realized. There are few implementations of terahertz building blocks using compound semiconductors at lower terahertz range. Unfortunately, these processes have low yield, are cost inefficient, and are not suitable for integration of digital blocks on the same chip. On the other hand, while CMOS can overcome these challenges, the best reported fmax of CMOS transistors fall well below terahertz frequencies.
To overcome these drawbacks, we have introduced systematic methodologies for designing circuits and components operating close to and beyond the conventional limits of the devices. These circuit blocks can effectively generate, combine, and process signals from multiple devices to achieve performances orders of magnitude better than the state of the art. The proposed techniques are general and can be used in any technology, including CMOS and other processes.
As an example, we show the implementation of a 482 GHz oscillator in a 65 nm CMOS process with an output power of 160W (-7.9 dBm), which is ~8,000 times more than any other CMOS sources at this frequency range. We also show a traveling-wave frequency multiplier for high power and wide-band terahertz and mm-wave signal generation. This signal source has twice the operating frequency and tuning range of the best reported CMOS multiplier and 10 times higher output power than the best reported CMOS realization. Moreover, to go beyond the conventional limitations of passive circuits, we developed a method to perform signal processing using 2-D electrical lattices. In this way, we introduced an electrical prism that can achieve a filtering quality factor that is orders of magnitude larger than the quality factor of the individual components in terahertz frequencies.
Omeed Momeni received the B.Sc. degree in Electrical Engineering from Isfahan University of Technology, Isfahan, Iran, and the M.S. degree in Electrical Engineering from University of Southern California, Los Angeles, in 2002 and 2006, respectively. He is currently working toward his Ph.D. degree at Cornell University, Ithaca, NY. His research interests include mm-wave and terahertz integrated circuits and systems.
From May 2004 to December 2006, he was with the National Aeronautics and Space Administration (NASA), Jet Propulsion Laboratory (JPL), to design L-band transceivers for synthetic aperture radars (SAR) and high power amplifiers for Mass Spectrometer applications. Mr. Momeni is the recipient of the Best Ph.D. Thesis Award from the Cornell ECE Department in 2011, the Best Student Paper Award at the IEEE Workshop on Microwave Passive Circuits and Filters in 2010, the Cornell University Jacobís fellowship in 2007 and the NASA-JPL fellowship in 2003.