Page 16 - An Introduction to Microelectromechanical Systems Engineering

Preface

The past few years have witnessed an increasing maturity of the MEMS industry
and a rapid introduction of new products addressing applications ranging from bio-
chemical analysis to fiber-optic telecommunications. The market size for MEMS
products has doubled in the past 5 years and is projected to grow at this fast rate for
the foreseeable future. The corresponding technology has enjoyed a fast pace of
development and has rapidly spread to institutions and companies on all inhabited
continents. A search of the keyword MEMS in all granted patents in the United
States since 1998 returns nearly 4,000 patents and references. Many devices have
left universities to go into commercial development, and several have reached the
stage of becoming products. It is therefore appropriate to extensively revise the text
to incorporate advances in the field, new products, as well as suggestions from the
readers.
As we revised the original text and added substantial new material, we strived to
retain the style characteristic of an introductory book intended for a broad audience
of scientists, engineers, students, and business executives. This revised edition con-
tinues to assume that the reader has no prior experience in MEMS technology but
does possess an understanding of basic scientific concepts equivalent to first-year
college physics and chemistry. The objective remained to introduce a select number
of representative demonstrators that are now or are soon to be commercially avail-
able. We added many more illustrations and pictures to aid the reader in developing
a familiarity with the technology. We also included throughout the text more practi-
cal tidbits that are useful to those who wish to apply this technology to their needs.
In this revision, we have expanded on the fabrication processes, adding new
methods and materials. The advantages and limitations of many micromachined
structures are covered in more detail. We divided the chapter on commercial struc-
tures into four chapters, each focusing on a specific application, and then expanded
each chapter with appropriate material covering new technical developments and
products. Chapter 4 is now specific to automotive and industrial applications, cov-
ering traditional products, such as pressure sensors, accelerometers, and yaw-rate
sensors, and new emerging products in valving and pumping. Chapter 5 now covers
the applications of MEMS in photonics, including displays, optical sensors, and
new products that are now common in fiber-optic telecommunications. The focus
of Chapter 6 is on applications in life sciences, with emphasis on new products and
developments specific to biochemical analysis and microfluidics. With the emer-
gence of wireless and radio frequency (RF) as a new market for MEMS technology,
we dedicated Chapter 7 to describe recent developments and introductions in this
promising area. In Chapters 4 through 7, we expanded where appropriate on the

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