**1. Introduction**

Nanolithography is the branch of nanotechnology concerned with the study and application of the nanofabrication of nanometer-scale structures, meaning nanopatterning with at least one lateral dimension between the size of an individual atom and approximately 100 nm. The term nanolithography is derived from the Greek words "nanos", meaning dwarf; "lithos", meaning rock or stone; and "graphein" meaning to write. Therefore the literal translation is "tiny writing on stone", however nowadays one understands something different whenever this term is associated with nanotechnology. Nanolithography is used e.g. during the nano‐ fabrication of leading-edge semiconductor integrated circuits (nanocircuitry), for nanoelec‐ tromechanical systems (NEMS) or for almost any other fundamental application across various scientific disciplines in nanoresearch.

This technology can be suitable to use in nanofabrication of various semiconducting Integrated Circuits (ICs), NEMS and for various applications in research. The modification in semicon‐ ductor chips at the nano-scale (in the range of 10-9 meter) is also possible. This method is contrasting to various existing nanolithographic techniques like Photolithography (Venugo‐ pal, 2011), Nanoimprint lithography (NIL), Scanning Probe Lithography (SPL), Atomic Force Microscope (AFM) nanolithography, Extreme Ultraviolet Lithography (EUVL) and X-ray Lithography.

In this chapter, the various nanolithographic fabrication techniques will be discussed in detail in which we will focus the various nano-patterning techniques/procedures suitable for device fabrication and their engineering applications. This technique is mainly used for nanofabrica‐ tion. Nanofabrication is the method in which the devices can be designed and manufactured with the dimensions in nanometers [Kim, 1999; Venugopal, 2011a, 2011b, 2011c).

The conventional fabrication techniques like Focused Ion Beam (FIB) and wet etching methods are able to remove or etch the parts in the range to micron scale (Kim, 2001). However, in recent

© 2013 Venugopal and Kim; licensee InTech. This is an open access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/3.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. © 2013 Venugopal and Kim; licensee InTech. This is a paper distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/3.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

days, patterning and etching have to be done in nanoscale for specific applications. For that nano-fabrication and nano-level manipulation are the options to choose. Nanomanupulation plays major role in the field of nanofabrication. Nanomanupulation is a technique in which some specific tools are used to manipulate the objects in nanoscale (Parikh, 2008). At present, Scanning Probe microscopic methods involved in AFM [Davis, 2003) and Scanning Tunneling Microscopy (STM) are being used to manipulate the objects in nanometer scale. Specifically, AFM is being used to move the atoms, carbon nanotubes, nanoparticles, various nano-scale objects and also to test integrated circuits. Instruments used in nanolithography include the Scanning Probe Microscope (SPM) and the AFM. The SPM allows surface viewing in fine detail without necessarily modifying it. Either the SPM or the AFM can be used to etch, write, or print on a surface in single-atom dimensions (Venugopal, 2012).

The main drawbacks in the existing lithographic techniques will be carefully analyzed in this chapter. Also the need of nano-patterning for the low-cost, high throughput surface patterning technologies will be presented in this chapter. In addition, the complete coverage of nanoli‐ thographic process which includes Introduction, Resists and Masks, Photon-based Lithogra‐ phy, Electron Beam Lithography, Ion Beam Lithography and emerging nanolithographic techniques will be discussed in detail. However, the alternate nanolithography techniques like Micro-contact printing, Nanoimprint Lithography, Scanned Probe Lithography, Dip-pen Lithography will also be discussed in detail in this chapter
