MEMS Introduction and Evolution:
– History of MEMS development from resonant-gate transistors to MOSFET microsensors.
– Introduction of the term MEMS in 1986 and integration with CMOS transistors.
– Evolution of MEMS manufacturing technologies like bulk and surface micromachining.
– Role of Analog Devices in industrializing surface micromachining.
– Impact of MEMS technology on creating low-cost accelerometers for various applications.
MEMS Materials and Processes:
– Use of materials like silicon, polymers, metals, and ceramics in MEMS fabrication.
– Crucial processes like deposition, lithography, and etching in MEMS manufacturing.
– Different types of etching methods including wet etching, dry etching, and xenon difluoride etching.
– Importance of patterning techniques like lithography in MEMS fabrication.
– Applications of materials and processes in creating MEMS sensors, actuators, resonators, and switches.
MEMS Applications and Industry Structure:
– Diverse applications of MEMS technology in industries like automotive, healthcare, and consumer electronics.
– Utilization of MEMS sensors in devices such as smartphones, wearables, and automotive systems.
– Role of MEMS actuators in optical devices, micropumps, and microvalves.
– Impact of MEMS resonators in timing devices and frequency control applications.
– Overview of the global MEMS market, industry structure, and market forecasts.
Etching Techniques in MEMS Fabrication:
– Deep reactive ion etching (DRIE) and its process involving the Bosch process.
– Various etching techniques like reactive-ion etching (RIE), plasma etching, and ion milling.
– Different modes of operation in plasma etching and gases used in the process.
– Anisotropic and isotropic plasma etching for achieving specific outcomes.
– Applications of etching techniques in creating complex MEMS structures and features.
NEMS Development and Research:
– Overview of NEMS manufacturing techniques like microfabrication and gas-phase micromachining.
– Applications of NEMS technology in vibratory gyroscopes, smart microphones, and RF switches.
– Research and development areas in NEMS including energy harvesting and ultrasound transducers.
– Projections for the MEMS systems market and advancements in stent development.
– Further reading references and resources for exploring NEMS technology and applications.
MEMS (micro-electromechanical systems) is the technology of microscopic devices incorporating both electronic and moving parts. MEMS are made up of components between 1 and 100 micrometres in size (i.e., 0.001 to 0.1 mm), and MEMS devices generally range in size from 20 micrometres to a millimetre (i.e., 0.02 to 1.0 mm), although components arranged in arrays (e.g., digital micromirror devices) can be more than 1000 mm2. They usually consist of a central unit that processes data (an integrated circuit chip such as microprocessor) and several components that interact with the surroundings (such as microsensors).
Because of the large surface area to volume ratio of MEMS, forces produced by ambient electromagnetism (e.g., electrostatic charges and magnetic moments), and fluid dynamics (e.g., surface tension and viscosity) are more important design considerations than with larger scale mechanical devices. MEMS technology is distinguished from molecular nanotechnology or molecular electronics in that the latter two must also consider surface chemistry.
The potential of very small machines was appreciated before the technology existed that could make them (see, for example, Richard Feynman's famous 1959 lecture There's Plenty of Room at the Bottom). MEMS became practical once they could be fabricated using modified semiconductor device fabrication technologies, normally used to make electronics. These include molding and plating, wet etching (KOH, TMAH) and dry etching (RIE and DRIE), electrical discharge machining (EDM), and other technologies capable of manufacturing small devices.
They merge at the nanoscale into nanoelectromechanical systems (NEMS) and nanotechnology.
