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.
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.
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.
