SBIR Phase I: Monolithic CMOS-Integration of Electroplated Copper MEMS Inertial Sensors

点击翻译按钮获取中文摘要

The broader impact/commercial potential of this project can lead to a revolution in the consumerelectronics market (mobile handsets, tablets, game consoles and wearables), wherein high performance,low power, small footprint multisensing (not limited to inertial sensing) platforms with timing devices,are all directly microfabricated on a common ASIC substrate. Sensor fusion can produce unprecedenteduser experiences by using data collected from all sensors and processed using machine learningalgorithms. This can further boost the sensor and timing markets that are expected to exceed $6 billiondollars by 2017. Moreover, the emergent Internet of Things (IoTs) and wearable markets are expected toreach $20 billion dollars by 2025, which can induce a rapid growth of such intelligent sensor fusionmarket. This can have a tremendous societal impact as wearable devices and IoT systems, interfaced withmobile platforms, can be used to monitor people?s health, safety and energy consumption. Making thesesolutions affordable will make it amenable to low income households not only in the US but also aroundthe world. It will also enable researchers to attain new frontiers of knowledge such as in digital sensorysystems. The long-term goals are to provide such intelligent sensor fusion solutions.This Small Business Innovative Research (SBIR) Phase I project seeks to demonstrate wafer-scalemicrofabrication of Micro-Electro-Mechanical Systems (MEMS) inertial sensors directly on theapplication specific integrated circuit (ASIC) substrates, by using electroplated copper (e-Cu) as astructural material. MEMS inertial sensors, such as gyroscopes and accelerometers, are pervasively usedin consumer electronics and automotive industries. Current trends are, however, requiring higher deviceperformance with smaller footprints, wherein multi-degree-of-freedom sensors are integrated on the samepackage, to enable new capabilities and user experiences. These requirements can be met bymonolithically fabricating inertial sensors on ASIC substrates, which is complex to achieve with siliconas a structural material. Using e-Cu, which is currently used for ASIC metal interconnects, as thestructural material, can enable easier routing to implement optimized mechanical structures, smallerdimensions given the high density of copper, extremely low cost as no wafer bonding is required, smallerform factors, multiple sensors on a single die, and much smaller parasitics providing low noise and higherperformance. Phase I tasks will be to wafer-scale fabricate and characterize e-Cu gyroscopes andaccelerometers with optimal performance parameters and address any drift problems that could emanatefrom structural reliability issues associated with the MEMS elements.