San Diego, CA, April 18, 2011 -- University of California, San Diego electrical engineering Ph.D. student Chirag Patel won the top prize – the Rudee Outstanding Poster Award – at Research Expo 2011 for his work on RF MEMS metal-contact switches. The switches could make their way into MRIs and other medical equipment, satellites, and electronic instrumentation such as spectrum analyzers and signal sources. Search all Research Expo poster abstracts. Read the Research Expo 2011 wrap up.
The winning switches route electrical signals using electrostatic fields. They are smaller, lighter and more reliable than the current technology known as “conventional electromagnetic relays” – which route electrical signals using current pulses and magnetic fields.
|Electrical engineering Ph.D. student Chirag Patel won the top prize – the Rudee Outstanding Poster Award – at Research Expo 2011 for his work on RF MEMS metal-contact switches. Search all Research Expo poster abstracts.|
Because satellite systems can be very expensive to put into space, the weight and space savings the new switches provide could lead to large cost savings, explained Patel, who works in the laboratory of Professor Gabriel M. Rebeiz from the Department of Electrical and Computer Engineering (ECE) at the UC San Diego Jacobs School of Engineering. The new switches also consume less power than conventional electromagnetic relays and could be used in demanding RF environments such as switching networks for automated test equipment, low-power base stations, and even cell phones of the future.
Patel, Rebeiz and their collaborators plan to implement the switch in different high frequency circuit configurations. Other students in the Rebeiz lab are developing different types of RF MEMS switches and tunable circuits.
At the Jacobs School, Rebeiz leads a Radio-Frequency Micro-Electro-Mechanical (RF MEMS) / Antennas group for Reconfigurable Radios, and co-leads a microwave/millimeter-wave/THz integrated circuits group for wireless communications and sensors.
At Research Expo 2011, Patel received some unexpected feedback on his work. During the final round of judging, the faculty judge from bioengineering asked Patel what would happen if he put his switch in water. “I thought about it, and I answered the question; but then I asked him why would you want to do that, and he said, ‘Well, that would be really useful for us in bioengineering,’” explained Patel, who was surprised that bioengineers would be interested in his work.
We would want to hire you tomorrow if this thing worked in water, the bioengineer said.
Lea Rudee Outstanding Poster at Research Expo 2011
This poster presents a novel electrostatic RF MEMS metal contact switch based on a tethered cantilever topology. The use of tethers results in a design that has low sensitivity to stress gradients, biaxial stresses, and temperature. A switch with a footprint of 160x190 um^2 and based on a 8-um thick gold cantilever with an Au/Ru contact is implemented on a high-resistivity silicon substrate and results in a total contact force of 0.8-1.2 mN at 80-90 V, a restoring force of 0.5 mN, a pull-in voltage of 61 V, an up-state capacitance of 24 fF, and an actuation time of 6.4 us. The device achieves a switch resistance of 2.4+/-1.4 to 1.8+/-0.6 ohms at 90-100 V in open laboratory environments (unpackaged). This design has the potential serve as a low-cost and high-reliability replacement for conventional electromagnetic relays in application areas such as automated testing equipment, high performance switching networks, medical devices, satellite systems, and defense.
Research Expo 2011 Best Poster Winners by Department
Poster #3: A Custom Integrated High Input Impedance Biopotential Amplifier for Non-Contact and Mobile Health (ECG/EEG) Monitoring
Yu Mike Chi (Professor Gert Cauwenberghs)
Computer Science and Engineering
Poster #79 Kremlin: Like Gprof, but for Parallelization
Donghwan Jeon, Saturnino Garcia (Professor Michael Taylor)
Electrical and Computer Engineering
Poster #130 High-Power, Large-Force, and Temperature-Stable Metal Contact Switches
Chirag Dipak Patel (Professor Gabriel Rebeiz)
Mechanical and Aerospace Engineering
Poster #157 Investigating the Use of Wing Sweep for Pitch Control of a Small Unmanned Air Vehicle
Kim Wright, Saam Ostovari, Anand Vaidya (Professor Thomas Bewley)
Poster #242 Thermal Stress and Buckling Detection in Rail by Non-Destructive Ultrasonic Testing
Claudio Nucera (Professor Francesco Lanza de Scalea)