The development of functional and reliable miniaturized devices including Micro Electro Mechanical Systems (MEMS) has stressed the manufacturing and packaging processes. The traditional micro fabrication techniques, such as lithography, physical vapor deposition (PVD), chemical vapor deposition (CVD) and etching, are layer-by-layer processes and mostly suitable for thin-filmed devices. LIGA (an acronym from German words for lithography, electroplating, and molding) is a newly developed process for thick metallic devices; however, it involves electroplating process and high quality molds, which are hard to move after electroforming. In all the processes mentioned above, masks and photoresist processing are inevitable, which complicates the whole process and increases the processing time and the total cost. It is also well known that packaging is another barrier for the advancement of MEMS. MEMS packaging, which is required to provide mechanical support, environmental protection and electrical connection to other system components, is much more complicated as compared to electronic components due to the moving structures, fluids or chemicals involved. It is the most expensive process in micromachining. Therefore, enabling tools and technologies are greatly needed for the fabrication and packaging of complicated devices and highly integrated micro assemblies. In this paper, we will present novel direct-print dispensing techniques and robust tools for 21st century manufacturing and packaging. Comparing to other dispensing technologies such as time-pressure needle dispensing, screen printing, pin transfer and jetting, nScrypt’s pumping techniques can dispense materials with precise volume control for 10’s of Pico liter resolution, accurate placement or alignment within a few microns, conformably print on exaggerated surfaces of 10’s of centimeters, and are extremely flexible with materials and patterns. The dispensing tip (nozzle) is optimized to reduce the pressure drop as compared to the traditional tubing needles. Comparing to traditional micro fabrication technologies, our direct-print dispensing technology is maskless and thus a cost effective process. While micro-dispensing is a solution based approach, it has the advantage of not being a wet process such as wet etching or electroplating. Direct-print dispensing of micro lines, micro dots, and three-dimensional structures will be presented. The technology has a wide range of applications in the manufacturing and packaging of micro/meso-scale devices and bio structures.
Physical Vapor Deposition of Cathode Materials for All Solid-State Li Ion Batteries: A Review
