MEMS 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,and MEMS devices generally range in size from 20 micrometres to a millimetre,although components arranged in arrays can be more than 1000 mm2. They usually consist of a central unit that processes data and several components that interact with the surroundings.
Surface micromachining builds microstructures by deposition and etching structural layers over a substrate. This is different from Bulk micromachining,in which a silicon substrate wafer is selectively etched to produce structures.
Microfabrication is the process of fabricating miniature structures of micrometre scales and smaller. Historically,the earliest microfabrication processes were used for integrated circuit fabrication,also known as "semiconductor manufacturing" or "semiconductor device fabrication". In the last two decades,microelectromechanical systems (MEMS),microsystems,micromachines and their subfields have re-used,adapted or extended microfabrication methods. These subfields include microfluidics/lab-on-a-chip,optical MEMS,RF MEMS,PowerMEMS,BioMEMS and their extension into nanoscale. The production of flat-panel displays and solar cells also uses similar techniques.
A MEMS electrothermal actuator is a microelectromechanical device that typically generates motion by thermal expansion. It relies on the equilibrium between the thermal energy produced by an applied electric current and the heat dissipated into the environment or the substrate. Its working principle is based on resistive heating. Fabrication processes for electrothermal actuators include deep X-ray lithography,LIGA,and deep reactive ion etching (DRIE). These techniques allow for the creation of devices with high aspect ratios. Additionally,these actuators are relatively easy to fabricate and are compatible with standard Integrated Circuits (IC) and MEMS fabrication methods. These electrothermal actuators can be utilized in different kind of MEMS devices like microgrippers,micromirrors,tunable inductors and resonators.
Microoptoelectromechanical systems (MOEMS),also known as optical MEMS,are integrations of mechanical,optical,and electrical systems that involve sensing or manipulating optical signals at a very small size. MOEMS includes a wide variety of devices,for example optical switch,optical cross-connect,tunable VCSEL,microbolometers. These devices are usually fabricated using micro-optics and standard micromachining technologies using materials like silicon,silicon dioxide,silicon nitride and gallium arsenide.
Kristofer S. J. Pister is a professor of electrical engineering and computer sciences at University of California,Berkeley and the founder and CTO of Dust Networks. He is known for his academic work on Microelectromechanical systems (MEMS),their simulation,his work on Smartdust,and his membership in the JASON Defense Advisory Group. He is the son of former Berkeley Dean of Engineering and former UC Chancellor Karl Pister.
Mark G. Allen is a professor specializing in microfabrication,nanotechnology,and microelectromechanical systems at the University of Pennsylvania,where he is currently Alfred Fitler Moore Professor of Electrical and Systems Engineering Director of the Singh Center for Nanotechnology,and leader of the Microsensor and Microactuator Research Group. Prior to his joining the University of Pennsylvania in 2013,he was with the Georgia Institute of Technology,where he was Regents' Professor of Electrical and Computer Engineering and the J.M. Pettit Professor in Microelectronics. While at Georgia Tech,he also held multiple administrative positions,including Senior Vice Provost for Research and Innovation;Acting Director of the Georgia Electronic Design Center;and Inaugural Executive Director of Georgia Tech's Institute for Electronics and Nanotechnology. He was editor in chief of the Journal of Micromechanics and Microengineering (JMM),and currently serves on the editorial board of JMM as well as the journal Microsystems and Nanoengineering.
Microelectromechanical system oscillators are devices that generate highly stable reference frequencies used to sequence electronic systems,manage data transfer,define radio frequencies,and measure elapsed time. The core technologies used in MEMS oscillators have been in development since the mid-1960s,but have only been sufficiently advanced for commercial applications since 2006. MEMS oscillators incorporate MEMS resonators,which are microelectromechanical structures that define stable frequencies. MEMS clock generators are MEMS timing devices with multiple outputs for systems that need more than a single reference frequency. MEMS oscillators are a valid alternative to older,more established quartz crystal oscillators,offering better resilience against vibration and mechanical shock,and reliability with respect to temperature variation.
A microscanner,or micro scanning mirror,is a microoptoelectromechanical system (MOEMS) in the category of micromirror actuators for dynamic light modulation. Depending upon the type of microscanner,the modulatory movement of a single mirror can be either translatory or rotational,on one or two axes. In the first case,a phase shifting effect takes place. In the second case,the incident light wave is deflected.
Nam-Trung Nguyen is a Vietnamese-Australian researcher in the fields of Microfluidics and Nanofluidics. He is notable for his work on nerve agent detector,PCR,Micromixer,Droplet-based Microfluidics,Micro Magnetofluidics,Liquid Marbles and Micro Elastofluidics. He is currently a Professor and Director of Queensland Micro and Nanotechnology Centre at Griffith University. He was a former Associate Professor at Nanyang Technological University,Singapore. Nguyen is a Fellow of ASME and a Senior Member of IEEE.
Kurt E. Petersen is an American inventor and entrepreneur. He is known primarily for his work on microelectromechanical systems. Petersen was elected a member of the United States National Academy of Engineering in 2001.
A nanoelectromechanical (NEM) relay is an electrically actuatedswitch that is built on the nanometer scale using semiconductor fabrication techniques. They are designed to operate in replacement of,or in conjunction with,traditional semiconductor logic. While the mechanical nature of NEM relays makes them switch much slower than solid-state relays,they have many advantageous properties,such as zero current leakage and low power consumption,which make them potentially useful in next generation computing.
Roger Thomas Howe is the William E. Ayer Professor of Electrical Engineering at Stanford University. He earned a B.S. degree in physics from Harvey Mudd College and M.S. and Ph.D. degrees in electrical engineering from the University of California,Berkeley in 1981 and 1984,respectively. He was a faculty member at Carnegie-Mellon University from 1984-1985,at the Massachusetts Institute of Technology from 1985-1987,and at UC Berkeley between 1987-2005,where he was the Robert S. Pepper Distinguished Professor. He has been a faculty member of the School of Engineering at Stanford since 2005.
Reza Ghodssi is a Professor in the Department of Electrical and Computer Engineering and the Institute for Systems Research (ISR) at the University of Maryland,College Park,where he directs the MEMS Sensors and Actuators Lab and holds the Herbert Rabin Distinguished Chair in Engineering. Ghodssi is also the Inaugural Executive Director of Research and Innovation for the A. James Clark School of Engineering at the University System of Maryland at Southern Maryland (USMSM). He is best known for his work designing micro- and nano-devices for healthcare applications,particularly for systems requiring small-scale energy conversion and biological and chemical sensing.
Andrei M. Shkel is a Professor of Mechanical and Aerospace Engineering at the University of California,Irvine. He was named Fellow of the Institute of Electrical and Electronics Engineers (IEEE) in 2014 "for contributions to micromachined gyroscopes". He served as the President of the IEEE Sensors Council (2020-2021). In 2021,he was elected to National Academy of Inventors (NAI) Fellow status. He is currently the Editor-in-Chief of the IEEE Sensors Letters.
A microvalve is a microscale valve,i.e. a microfluidic two-port component that regulates the flow between two fluidic ports. Microvalves are basic components in microfluidic devices,such as labs-on-a-chip,where they are used to control the fluidic transport. During the period from 1995 to 2005,many microelectromechanical systems-based microvalves were developed.
A piezoelectric microelectromechanical system (piezoMEMS) is a miniature or microscopic device that uses piezoelectricity to generate motion and carry out its tasks. It is a microelectromechanical system that takes advantage of an electrical potential that appears under mechanical stress. PiezoMEMS can be found in a variety of applications,such as switches,inkjet printer heads,sensors,micropumps,and energy harvesters.
Albert P. Pisano is an American academic. He serves as dean of the Jacobs School of Engineering at the University of California San Diego,a position he has held since September 2013. Pisano publishes a monthly Dean's column that introduces the monthly news email from the UC San Diego Jacobs School of Engineering. The January 2022 dean's column,"Math matters to all of us" triggered significant conversation on Pisano's LinkedIn feed.
Richard Manning White was an electrical engineer and a professor emeritus in the Department of Electrical Engineering and Computer Sciences at UC Berkeley and a Co-Founding Director of the Berkeley Sensor &Actuator Center (BSAC). He and Richard S. Muller founded the BSAC in 1986. They received 2013 IEEE/RSE James Clerk Maxwell Medal for pioneering innovation and leadership in MEMS technology. White is known for inventing the Interdigital Transducer (IDT) and for his surface acoustic wave work,he received the 2003 Rayleigh Award. He received the IEEE Cledo Brunetti Award in 1986.
Vapor etching refers to a process used in the fabrication of Microelectromechanical systems (MEMS) and Nanoelectromechanical systems (NEMS). Sacrificial layers are isotropically etched using gaseous acids such as Hydrogen fluoride and Xenon difluoride to release the free standing components of the device.
