Nanotechnology is concerned with the research and development of nanometerscale (1∼100 nm) devices and materials [1,2]. In principle, two opposing routes towards the nanoscale can be pursued: top-down and bottom-up. The top-down route approaches the nanoscale starting from macroscopic objects and with the aid of lithographic techniques. These are the methods of choice in the manufacturing of microstructures and micromachines with sizes in the range of 1-100 μm [3]. The main factor limiting the sizes of features patterned with optical lithography is represented by the wavelength of the radiation employed. Both electron- and ion-beam lithographic techniques are currently capable of manufacturing patterns of sizes close to or below 200 nm thereby extending the resolution limits of conventional optical lithography [4].