Applications of microelectromechanical systems (MEMS) and microfabrica-
tion have spread to different fields of engineering and science in recent years.
Perhaps the most exciting development in the application of MEMS technol-
ogy has occurred in the biological and biomedical areas. In addition to key
fluidic components, such as microvalves, pumps, and all kinds of novel
sensors that can be used for biological and biomedical analysis and mea-
surements, many other types of so-called micro total analysis systems (TAS)
have been developed.
For more than three decades, Micro Electro Mechanical Systems (MEMS) have
steadily transitioned out of research labs and into production forming a more than $10 billion
market [1]. MEMS devices such as accelerometers, pressure sensors and microphones, to name
a few, have seen immense utilization, particularly in the consumer electronics market, because
of their compact sizes and minute power consumptions. In addition, these devices benefit from
batch fabrication, which has enabled year-over-year reductions in cost [2]. In recent years,
Micro-Electro-Mechanical Systems (MEMS) are miniature systems composed
ofintegratedelectricalandmechanicalpartstosenseand/orcontrolthingsonaμmscale.
The concept of MEMS is attributed to Richard Feynman’s famous talk on December
29th, 1959 [2,3]. Dr. Feynman foresaw many aspects of future MEMS development
with his insight in microphysics. In particular, material properties in the μm scale are
differentfrombulkpropertiesandthescalingdownofintegratedcircuits(IC)fabrication
technology has been a major driving force of MEMS development.
A few years ago I stood before an audience at a customer’s facility
explaining the merits of micromachining technology. The small
conference room was packed, and all ears were attentive. Everyone was
eager to learn about thismysteriousbuzzword, “MEMS.”Although many
in the audience were nodding in a sign of comprehension, the glazed
lookson their facesbetrayed them. Thisexperience isnot unique, but one
that isrepeated frequently in auditoriumsaround the world.
Recent advancements in nanotechnology (NT) materials and growth of micro/
nanotechnology have opened the door for potential applications of microelectro-
mechanical systems (MEMS)- and NT-based sensors and devices. Such sensors and
devices are best suited for communications, medical diagnosis, commercial, military,
aerospace, and satellite applications. This book comes at a time when the future and
well-being of Western industrial nations in the twenty-first century’s global eco-
nomy increasingly depend on the quality and depth of the technological innovations
they can commercialize at a rapid pace.
Over many years, RF-MEMS have been a hot topic in research at the technology
and device level. In particular, various kinds of mechanical Si-MEMS resonators
and piezoelectric BAW (bulk acoustic wave) resonators have been developed. The
BAW technology has made its way to commercial products for passive RF filters,
in particular for duplexers in RF transceiver front ends for cellular communica-
tions. Beyond their use in filters, micromachined resonators can also be used in
conjunction with active devices in innovative circuits and architectures.
Microengineering and Microelectromechanical systems (MEMS) have very few
watertight definitions regarding their subjects and technologies. Microengineering
can be described as the techniques, technologies, and practices involved in the
realization of structures and devices with dimensions on the order of micrometers.
MEMS often refer to mechanical devices with dimensions on the order of
micrometers fabricated using techniques originating in the integrated circuit (IC)
industry, with emphasis on silicon-based structures and integrated microelectronic
circuitry. However, the term is now used to refer to a much wider range of
microengineered devices and technologies.
