MICE





				A New Role for MICE at the NSF Center In Thermal Spray Research The near-ubiquity achieved so rapidly by cell phones is the leading edge of a tidal wave of new mobile technologies that is preparing to invade the marketplace. Field-deployable sensing, communications and positioning devices represent some of the most exciting of these technologies, timely in part because of geopolitical events that are still unfolding. The fabrication and manufacturing of these devices is challenged by new demands for performance; a new era of sensors and electronics is made possible by a novel modification of thermal spray technology being developed by one of the University's two NSF Materials Research Science and Engineering Centers (MRSECs) for direct-write fabrication of electronics and sensors, with support from the Defense Advanced Research Projects Agency MICE (Mesoscopic Integrated Conformal Electronics) program. The new thermal spray based method permits the manufacture of miniaturized and rugged electronic devices on any surface, flat or not, including metals, polymers, semi-conductors and ceramics, through the 3-dimensional integration of functional elements and batteries or other power sources. This breakthrough technology offers unprecedented capability to integrate structural materials with sensors for state awareness and damage monitoring, especially in harsh environments, For instance, the technology enables integration of temperature and strain sensors on turbine engine components used for aircraft or power generation. Furthermore, the process capability allows packaging of dissimilar materials in mulitlayers for functional applications. For example, a transmit/receive antenna could be sprayed onto a soldier's helmet, continuously receiving signals from a GPS satellite and transmitting his/her position to a command post. The Center's basic research, supported through the NSF MRSEC program, has significantly expanded scientific understanding of the process. DARPA's support for the new effort has facilitated the development and demonstration of process technologies, application tools, thick film electronic materials, and integratable sensor devices. . This method allows for direct-write conformal - i.e. non-flat surface - deposition of electronic circuits and sensor materials in mesoscale thick-film sizes, i.e. greater than 5 microns (ten-thousandths of a centimeter), or about a tenth of the diameter of a human hair. The direct-write approach eliminates the additional processing steps, time and costs required for conventional mask manufacturing methods for electronics. Rather than using stencil-like patterns, etching substances and solvents to produce a specific pattern and remove the excess materials from the manufacturing process, the new technology employs computer-controlled robotics to produce the design in a single step, reducing materials waste to near zero while cutting manufacturing costs and permitting the patterning of varied and complex configurations through CAD/CAM. The technology's ability to perform the deposition at relatively low temperatures (in many cases near ambient air temperature) offers extraordinary materials versatility and enables deposition on conformal surfaces. Thermal spray is a continuous melt-spray process, in which particles of virtually any material are melted and accelerated to high velocities, solidifying rapidly into a well-bonded deposit on the target surface. While the process has been known for decades -- a bridge between England and Wales that was thermal-sprayed with a metal coating more than 50 years ago still looks "like new" -- its use was previously based on know-how rather than a scientific understanding of process, synthesis and coatings properties. The NSF Center has pioneered in developing physics-based process models, design tools and materials development strategies. Stony Brook's other MRSEC studies polymers.