Overview

Devices developed over the years by the institute.

What are MEMS?

MEMS/NEMS (Micro-Electro-Mechanical Systems/Nano –Electro-Mechanical Systems) are the merger of the IC world with the mechanical world. Using established IC fabrication techniques along with additional chemical and mechanical processes, microscopic structures and devices can be constructed. These structures bridge the gap between the "electrical/computer world" and the real physical world at the microscopic level. This allows integration of the Micro/Nano sensors and actuators with IC circuitry at an unprecedented level.

Importance of MEMS/NEMS

Micro/NanoElectroMechanical Systems (MEMS) technology offers the opportunity to produce mechanical, electromechanical, and electrochemical devices with the same unprecedented levels of miniaturization, and functionality as modern very large scale integrated (VLSI). MEMS is a rapidly growing segment of the U.S. semiconductor industry with a multi-billion-dollar market expanding over the next decade. This emerging technology utilizes mechanical structures, fabricated using the microfabrication techniques perf ected by the semiconductor industry, to perform sensing and actuation functions. Commercial applications for this technology include pressure sensors, fluid regulation and control, optical switching, mass data storage, and chemical and biological sensing and control. The number of MEMS based applications is increasing at a rapid pace particularly in the field of microsensors that integrate the MEMS sensor with the signal processing circuits on the same chip to produce smart sensors. Recently, there has been a large number of emerging sensor products based on MEMS technologies which has received market acceptance. The wide spectrum of research topics in this area includes the development of new materials and technology which push sensors beyond current limitations, such as high temperature devices, submicron devices, and new sensors devices.

Technical Interdisciplinary of the MEMS Research

Manufacturers and users of MEMS/NEMS technology must be able to understand the behavior of those structures and accurately model their behaviors. The design and characterization of MEMS/NEMS devices requires a knowledge of the material properties involved, an awareness of semiconductors circuit design methodology, the mechanical properties of the devices, and the ability to model the devices accurately. MEMS/NEMS device research involves the characterization of MEMS/NEMS material properties which include material residual stresses, thermal expansion, conductivity, mechanical strength, fatigue and fracture resistance, and others. This research spans a wide range of disciplines in electrical engineering, mechanical engineering and material sciences, and applications of MEMS devices in several disciplines. Among these disciplines, the key factor for the rapid progress of microsensors and MEMS has been silicon microfabrication technology and silicon micromachining. This refers to fashioning microscopic mechanical parts out of a silicon substrate or on a silicon substrate. The technology requires the knowledge of chemists, physicists, electrical engineers, mechanical engineers, and material scientists. This wide range of interdisciplinary skills is well represented in the George Washington University's Schools, Faculty, and Institutes.

GWU MEMS/NEMS Research

The MEMS research at GWU is focused on using different technologies combined with pre- and/or post-processing steps. Several devices have been realized using CMOS technology, including RF MEMS devices, Power Sensors, SAW Gas Sensors, and many others. The research group uses CMOS to add active circuitry to the sensor, hance creating a complete system.

Examples Of CMOS MEMS Devices Delveloveped at GWU

Chemical Gas Sensor:


Published in:
I. Voiculoescu, M.E. Zaghloul, A. McGill, G. Fedder, "Electrically Actuated Resonant Microcantilever In CMOS Technology For Detection of Chemical Weapons" the IEEE Sensors Journal, Special Issue on Sensors for prevention of Terrorist Acts, Col. 4, No. 4, August 2005, pp 641-647. (BEST PAPER AWARD IEEE SENSORS JOURNAL 2007)

CMOS Surface Acoustic Wave (SAW) Resonator:


Published in:
Nordin, M.E. Zaghloul, "Modeling and fabrication of CMOS Surface acoustic Resonators", IEEE Transaction of Microwave Theory and Techniques, Volume 55, Number 5, May 2007, pp992-100