In the world of nanoscale systems, there are three routes to take to assemble a nanoscale material or component into a useful system that meets a well-defined requirement as defined by the systems engineer. One route is to use a topdown assembly approach and guide the nanoscale components or materials into a desired configuration using techniques borrowed from traditional system fabrication processes such as printing, depositing, or etching. Another route is to “let nature take its course” and to rely on bottom-up assembly techniques such as self-assembly, which rely on the minimization of free energy to assemble nanoscale materials and components into useful structures, devices, and ultimately systems. The third method is a hybrid method that when necessary in system processing steps, utilizes techniques that are both top-down

and bottom-up in nature to leverage the best parts of both assembly styles at the right time in the fabrication. The topdown assembly route to create nanoscale systems will be discussed in detail in this chapter, while bottom-up assembly will be examined closely in Chapter 9. The hybrid method will not be discussed further, as it is a variable method that will draw from the techniques described in the top-down and bottom-up chapters of this book.