Micro-Electro-Mechanical Systems

Abstract

The key concept of micro electro-mechanical systems (MEMS) technologies is to extend the VLSI fabrication capability to realize three-dimensional microsystems, which are composed of electrical, mechanical, chemical, and optical elements. Using VLSI fabrication processes such as photolithography, film deposition, and etching, it is possible to obtain submicrometer-precision structures in a large quantity with excellent alignment between each other. The optical application is one of the most prospective applications, because the MEMS technology has superior features for the optical field. Movable structures such as micromirrors can be made by micromachining processes. The chapter describes the MEMS technology and its application to optics. It deals with typical examples among those activities including optical switches, scanners, sensors, integrated optical encoders, tunable Vertical Cavity Surface Emitting Lasers/filters, and spatial light modulators. Microactuators are the key devices for MEMS to perform physical functions. Many types of microactuators have been successfully operated. They are categorized in two types: based on driving forces and based on mechanisms.