In tech zone
Ved Narayan takes a look at the various
systems and tools used for breaking into the
magical world of micro technology
The introduction of Micro Electro-
Mechanical Systems (MEMS) specific
capabilities in mainstream design tools is
helping pave the way to greater use of
micro technology. These tools shall help companies
facing miniaturisation challenges break new ground,
innovate products, devices and micro-manufacturing
technologies and broaden the use of microelectromechanical
systems for a variety of applications.
Much of the groundbreaking work in this
emerging field took place in the semiconductor
industry, where the drive to produce silicon
integrated circuits steered research and development
into the creation of manufacturing processes that
would yield features and components that one can
barely see with the naked eye. Although ICs were
the initial focus for the development of microdesign
methodologies, manufacturers are leveraging
these technologies to develop and produce MEMS
and miniaturised mechanical devices to satisfy the
market demand for miniaturisation.
Until the last few years, MEMS and micromechanical
design and production were more
research-oriented activities that took place in
university labs than in commercially viable
manufacturing enterprises. The design and
manufacturing tools used for MEMS and micromechanical
design were highly specialised and very
few engineers knew how to accomplish micro-design
without developing manufacturing techniques and
enabling technologies as part of the design process.
Much of this work was done using 2-D layouts to
represent configurations of the separate layers of
silicon that are deposited sequentially to create a
conventional MEMS component.
However, the availability of MEMS-specific design
functionality in mainstream computer-aided design
(CAD) tools is driving the cost-effective development
of MEMS and miniaturised mechanical devices for
commercial products.
Potential applications for MEMS are wide ranging.
Any miniaturised electrical system that requires a
mechanical component is a candidate, including
inertial sensors, switches and relays, resonators and
mechanical filters, micro-capacitors, inductors and
probes, as well as inclinometers, valves, DNA
sequencers and chemical and biological agent sensors.
Whatever the application, the driving force behind
micro-mechanical system development is size and
weight. Unlike integrated circuits, which focus on
passing electrical current through extremely small
circuits, all MEMS components have some mechanical
element and most have at least one movable part.
While depositing several thin layers of silicon and
etching material to create layer configurations works
well for manufacturing ICs and some MEMS devices,
new manufacturing processes are emerging that give
designers more options for optimising the mechanical
aspects of MEMS.
For years, the primary material available to MEMS
designers was silicon and the only manufacturing
processes available emanated from the semiconductor
industry. These processes with highly specialised tools,
had limited designs to the use of four or five layers of ....
....CONTD
