"This award is funded under the American Recovery and Reinvestment Act of 2009 (Public Law 111-5)."
The objective of this research is to develop a waveguide radio-frequency micro-electromechanical systems tunable filter as a unique three-dimensional microstructure in silicon. The approach is based on combining 1) bulk micromachining for miniaturized cavity implementation, 2) surface micromachining for radio-frequency micro-electromechanical systems planar circuit development, and 3) high-aspect-ratio-microstructure fabrication to bias the planar circuit embedded inside the cavity using vertical signal routing.
With respect to intellectual merit, the proposed highly miniaturized three-dimensional filter enables vertical integration with front-end electronics to create a fully functional frequency-agile microstructure through the major paradigm shift of combining three aspects of microfabrication for the first time. The filter provides superior electrical performance including ultra-high selectivity, wideband tuning, low loss, high linearity and extremely low power consumption for tuning. A dielectric-filled, evanescent-mode, micromachined waveguide filter is proposed to provide low loss, and also to reduce the size of the filter relative to its bulky resonant-mode counterpart. A planar electrostatic micro-electromechanical systems circuit performs the task of tuning over a very wide range with ultra-low power consumption and excellent linearity by loading the capacitive posts fabricated inside the cavity. Vertical signal routing provides a novel approach to successfully combine two and three-dimensional microstructures and make the high performance vertically integrated tunable filter feasible.
With respect to broader impact, the project has the potential to advance the development of novel microfabrication techniques and state-of-the-art microwave circuits. Providing a solution for ultra-miniaturized, high performance, frequency-agile filters enhances capabilities for reconfigurable systems including software-defined radios, electronic warfare systems, radars and instrumentation systems. The proposed project also promotes education and outreach activities by creating research projects for graduate and undergraduate students and extra-curricular summer activities for high school teachers and students. Educational opportunities for minorities and under-represented groups will be explored by collaborating with Enrichment Experience Engineering teacher summer research program at Texas A&M University to provide a one month workshop for minority high school teachers in science and engineering. Also, annual Society of Women Engineers summer camps inspire high school women to join the engineering program. The research and educational results of this work will be disseminated to academic, industrial and government sectors.
