Page 29 - An Introduction to Microelectromechanical Systems Engineering

8 MEMS: A Technology from Lilliput

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Figure 1.1 Volume manufacturing is essential for maintaining profitability.

Standards

Few disagree that the burgeoning MEMS industry traces many of its roots to the inte-
grated circuit industry. However, the two market dynamics differ greatly with severe
implications, one of which is the lack of standards in MEMS. Complementary
metal-oxide semiconductor (CMOS) technology has proven itself over the years to be
a universally accepted manufacturing process for integrated circuits, driven primarily
by the insatiable consumer demand for computers and digital electronics. By con-
trast, the lack of a dominant MEMS high-volume product (or family of products) and
the unique technical requirements of each application have resulted in the emergence
of multiple fabrication and assembly processes (the next chapters will introduce
them). Standards are generally driven by the needs of high-volume applications,
which are few in MEMS. In turn, the lack of standards feeds into the diverging
demands of the emerging applications.

The Psychological Barrier

It is human nature to cautiously approach what is new, for it is foreign and untested.
Even for the technologically savvy or the fortunate individual living in high-tech
regions, there is a need to overcome the comfort zone of the present before engaging
the technologies of the future. This cautious behavior translates to slow acceptance
of new technologies and derivative products as they get introduced into soci-
ety. MEMS acceptance is no exception. For example, demonstration of the first
micromachined accelerometer took place in 1979 at Stanford University [11]. Yet it
took nearly 15 years before it became accepted as a device of choice for automotive
airbag safety systems. Naturally, in the process, it was designed and redesigned,
tested, and qualified in the laboratory and in the field before it began gaining the
confidence of automotive suppliers. The process can be lengthy, especially for
embedded systems (see Figure 1.2).