Editing Nanotechnology (section)

===Lithography===
Various techniques of lithography, such as [[optical lithography]], [[X-ray lithography]], dip pen lithography, [[electron beam lithography]] or [[nanoimprint lithography]] offer top-down fabrication techniques where a bulk material is reduced to a nano-scale pattern.

Another group of nano-technological techniques include those used for fabrication of [[Ion track technology (track etching)|nanotubes]] and [[Ion track technology (track replication)|nanowires]], those used in semiconductor fabrication such as deep ultraviolet lithography, electron beam lithography, focused ion beam machining, nanoimprint lithography, [[atomic layer deposition]], and [[molecular vapor deposition]], and further including molecular self-assembly techniques such as those employing di-block [[copolymer]]s.<ref name="pmid26295171">{{cite journal | vauthors = Kafshgari MH, Voelcker NH, Harding FJ | title = Applications of zero-valent silicon nanostructures in biomedicine | journal = Nanomedicine | volume = 10 | issue = 16 | pages = 2553–71 | year = 2015 | pmid = 26295171 | doi = 10.2217/nnm.15.91 }}</ref>

====Bottom-up====
In contrast, bottom-up techniques build or grow larger structures atom by atom or molecule by molecule. These techniques include chemical synthesis, [[self-assembly]] and positional assembly. [[Dual-polarization interferometry]] is one tool suitable for characterization of self-assembled thin films. Another variation of the bottom-up approach is [[molecular-beam epitaxy]] or MBE. Researchers at [[Bell Telephone Laboratories]] including [[John R. Arthur Jr.|John R. Arthur]]. [[Alfred Y. Cho]], and Art C. Gossard developed and implemented MBE as a research tool in the late 1960s and 1970s. Samples made by MBE were key to the discovery of the [[fractional quantum Hall effect]] for which the [[List of Nobel laureates in Physics|1998 Nobel Prize in Physics]] was awarded. MBE lays down atomically precise layers of atoms and, in the process, build up complex structures. Important for research on semiconductors, MBE is also widely used to make samples and devices for the newly emerging field of [[spintronics]].

Therapeutic products based on responsive [[nanomaterials]], such as the highly deformable, stress-sensitive [[Transfersome]] vesicles, are approved for human use in some countries.<ref>{{cite journal | vauthors = Rajan R, Jose S, Mukund VP, Vasudevan DT | title = Transferosomes - A vesicular transdermal delivery system for enhanced drug permeation | journal = Journal of Advanced Pharmaceutical Technology & Research | volume = 2 | issue = 3 | pages = 138–143 | date = July 2011 | pmid = 22171309 | pmc = 3217704 | doi = 10.4103/2231-4040.85524 | doi-access = free }}</ref>