Introduction t 8 . Introduction to Micro - / Nanofabrication

This chapter outlines and discusses important microand nanofabrication techniques. We start with the most basic methods borrowed from the integrated circuit (IC) industry, such as thinfilm deposition, lithography and etching, and then move on to look at microelectromechanical systems (MEMS) and nanofabrication technologies. We cover a broad range of dimensions, from the micron to the nanometer scale. Although most of the current research is geared towards the nanodomain, a good understanding of top-down methods for fabricating micron-sized objects can aid our understanding of this research. Due to space constraints, we focus here on the most important technologies; in the microdomain these include surface, bulk, and high-aspect-ratio micromachining; in the nanodomain we concentrate on e-beam lithography, epitaxial growth, template manufacturing, and self-assembly. MEMS technology is maturing rapidly, with some new technologies displacing older ones that have proven to be unsuited to manufacture on a commercial scale. However, the jury is still out on methods used in the nanodomain, although it 8.1 Basic Microfabrication Techniques.......... 232 8.1.1 Lithography ................................. 232 8.1.2 Thin-Film Deposition and Doping .. 233 8.1.3 Etching and Substrate Removal ...... 238 8.1.4 Substrate Bonding........................ 243