Optical MEMS and nanophotonics

Abstract

Micro-electro-mechanical systems (MEMS) technology ignites major breakthroughs in several research areas. Optics/photonics is one of these research fields impacted by MEMS techniques. Generally, microoptical elements with sizes ranging from a few microns to a few millimeters belong to the category of optical MEMS. They are inherently suited for cost effective wafer scale manufacturing as the processes are derived from the semiconductor industry. The advantages of applying microelectronics technology to silicon micromechanical devices were presented by Petersen in his classic paper, 'Silicon as a Mechanical Material'[1]. The ability to steer or direct light is one of the key requirements in optical MEMS. In the past two decades since Petersen published his silicon scanner[2], the field of optical MEMS has experienced explosive growth[3,4]. In the 80's and early 90's, displays were the main driving force for the development of micromirror arrays. Portable digital displays are common places and head mount displays are now commercially available. In the past decade, telecommunications has become the market driver for Optical MEMS. The demand for routing internet traffic through fiber optic networks pushes the development of both digital and scanning micromirror systems for large port-count all-optical switches. In the biomedical arena, microoptical scanners promise low-cost endoscopic 3D imaging systems for in vivo diagnostics. Thanks to the ongoing improvement of fabrication technologies, nano-electro-mechanical systems (NEMS) have become feasible and have steadily attracted attention in the fields of optics and photonics. Nano-photonics is particularly promising in guided-wave devices as the structural dimensions (a few hundred nanometers) are close to the optical wavelengths of interest. This chapter summarizes the state of the art of Optical MEMS and nano-photonics technologies and applications. It is organized into the following sections: Section 10.1 describes the generic actuation mechanisms commonly used for MEMS and NEMS devices. Section 10.2 discusses the applications, dividing into three categories including 'Display, Imaging, and Microscopy,' 'Optical Communication,' and 'NanoPhotonics'.