Silicon Carbide Micro/Nano Systems for Harsh Environment and Demanding Applications

摘要

Micro/nano systems enable the development of smart products and systems by augmenting the computational ability of microelectronics with the perception and control capabilities of sensors and actuators. Micro/nano systems are also known as micro- and nano-electromechanical systems (MEMS and NEMS), and have been commercialized in a wide range of applications including crash sensing, blood pressure measurement, optical projection, fluid flow control to name a few. Silicon, in single- and polycrystalline form, has traditionally been the platform semiconductor material underpinning the fabrication of the mechanical and electronic elements of micro/nano systems. However, the material properties of silicon impose limitations on its use in harsh environment and demanding applications. Such applications involve operation in the presence of high temperatures, corrosive media, high shock loads, erosive flows, and/or high radiation, or involve performance requirements for the mechanical elements that are beyond silicon's capabilities. Silicon carbide (SiC) is an alternative platform semiconductor material that enables such applications because of its wider bandgap and higher melting/sublimation temperature, elastic modulus, fracture toughness, hardness, chemical inertness, and thermal conductivity. This overview highlights recent material, process, and device advances in the context of the effort to establish a SiC micro/nano systems technology. This technology enables sensing and actuation in propulsion, power generation, resource exploration, nuclear reactor instrumentation, deep space exploration, and communications to name a few.