Process development for moving mechanical assemblies

Abstract

Moving Mechanical Assemblies could be considered a type of microelectromechanical systems (MEMS) and are usually small integrated devices or systems that combine electrical and mechanical components. They range in size from the millimeter level to the submicron level, usually with a moving or suspended part, and integrated together with at least some electronic circuitry. MEMS are presently being considered for both microsensor and micro-actuator applications. Sensors detect physical and chemical signals. Actuators can drive micro-components, including optical mirrors, displays, fluid controllers and turbines. The current generation of MEMS are fabricated using processing technology such as lithography and etching derived from silicon (Si) microelectronics. One tends to compare MEMS with silicon microelectronics but there is a fundamental difference. MEMS require a greater diversity of models, simulations and packaging approaches than ICs. MEMS further extend the fabrication techniques developed for the integrated circuit industry to add mechanical elements such as beams, bridges, gears, diaphragms and springs to devices. Another distinction is that typically 3-D structures required for many MEMS applications (optical, mechanical, etc) create a need for nonstandard materials and non-polygonal geometries. MEMS are not about any one application or device, nor are they defined by a single fabrication process or limited to a few materials. They are a fabrication approach that conveys the advantages of miniaturization, multiple materials components and microelectronics to the design and construction of integrated electromechanical systems. In addition, MEMS are not only about miniaturization of mechanical systems; they also provide a new paradigm for designing mechanical devices and systems.