Page 24 - Microsensors, MEMS and Smart Devices - Gardner Varadhan and Awadelkarim

INTRODUCTION

Figure 1.8 Some of the many fundamental techniques required to make MEMS devices. From
Fatikow and Rembold (1997)

for the relatively slow emergence of a complete MEMS has been the complexity of the
manufacturing process. Figure 1.8 details some new materials for MEMS and the various
microtechnologies that need to be developed.
In Chapter 3, some of the new materials for MEMS have been introduced and their
fundamental properties have been described. One attractive solution to the development
of MEMS is to make all the techniques compatible with silicon processing. In other
words, conventional complementary metal oxide semiconductor (CMOS) processing is
combined with a pre-CMOS or post-CMOS MST. Because of the major significance
of this approach, Chapters 12 to 14 have been dedicated to the topic of interdigitated
transducers (IDTs) and their use in microsensors and MEMS devices.
The present MEMS market is relatively staid and mainly consists of some simple
optical switches for the communications industry, pressure sensors, and inertia! sensors
for the automotive industry, as shown in Figure 1.9. This current staidness contrasts with
the potential for MEMS, which is enormous. Table 1.1 is taken from a recent report
on the world market for MEMS devices. The major growth areas were identified as
microfluidics and photonics and communications. However, there have been some exciting