NSF Award
0339236
This Small Business Innovative Research (SBIR) Phase I project seeks to enhance the surface micromachining technology (the SUMMiT V technology) -- with an additional structural and interconnect level. The resultant technology, SUMMiT VII, should enable the monolithic fabrication of devices to address the most difficult Micro-electro-mechanical systems (MEMS) product requirements. The primary technical challenge associated with the additional polysilicon and oxide levels is the management and mitigation of stress in the films deposited on the wafer. Left unchecked, this stress would lead to excessive wafer bow that could affect the accuracy of subsequent lithography processes or make the wafers impossible to handle with automated equipment. The goal of this research program is to better understand and characterize the stress in the additional SUMMiT levels during the fabrication process. A variety of techniques to mitigate this stress will be analyzed to ensure SUMMiT VII devices can be built reliably and uniquely positioned to complete this research program. <br/><br/>Emerging MEMS device requirements in fields like adaptive optics and advanced tunable radio-frequency (RF) devices are starting to exceed the capabilities of even the most sophisticated surface micromachining technologies. The proposed transition to SUMMiT VII mirrors the progression of integrated circuits and printed circuit boards, where the availability of additional vertical levels permitted the design of smaller, cheaper devices with even better performance and functionality. The incremental mechanical sophistication of the new structural level in SUMMiT VII permits design enhancements like flatter mirror surfaces, integrated particle and electrostatic shields, and increased device robustness and reliability. The additional interconnect level permits larger, denser arrays and removes many of the routing constraints inherent in any single level interconnect scheme. SUMMiT VII should permit the enhancement of existing MEMS application areas, but could also enable solutions for product applications where current MEMS technologies simply fall short. SUMMiT VII should enable a world-class solution in ophthalmic adaptive optics, a MEMS market estimated at $20M per year. The annual market for high performance tunable capacitors is estimated at $120M, part of a total RF MEMS opportunity, which exceeds $1 billion annually.
