Nano technology-Definition:                                                                                                                                                                                                                                      BACK

This is a term that has entered into the general and scientific vocabulary only recently but has been used at least as early as 1974 by Taniguchi. Nanotechnology is defined as a technology where dimensions and tolerances are in the range of 0.1-100 nm (from size of the atom to about the wavelength of light) play a critical role. This definition is however too general to be of practical value because it could as well include, for example, topics as diverse as X-ray crystallography, atomic physics, microbial biology and include the whole of chemistry! The field covered down by nanotechnology is narrowed down to manipulation and machining within the defined dimensional range by technological means, as opposed to those used by craftsman, and thus excludes, for example, traditional glass polishing or glass colouring techniques. Another popular definition for Nano technology is : “Nano technology relates to the ability to build functional devices based on the controlled assembly of nano scale objects for specific technological applications.”


Difference between Nano science and Nano technology:

Study on fundamental relationships between physical properties and phenomena and material dimensions in the nanometer scale referred to as Nano science.

            But Nano technology is the application of these nano structures and principles behind them to make nano scale devices and to produce new materials.


Feynman predictions on Nano technology:

One of the first to advocate a future for nanotechnology was Richard Feynman, a Physics Nobel laureate who died in 1988. In late 1959 at the California Institute of Technology, he presented what has become one of 20th century science’s classic lectures entitled “There is Plenty of Room at the Bottom”. This classic lecture has become part of the nanotechnology community’s founding liturgy.

 Feynman got his motivation from biology since biological systems can be exceedingly small. He said, “Many of the cells are very tiny, but they are active; they manufacture substances; they walk around; they wiggle; and they do all kind of marvelous things–all on a very small scale. Also, they store information. Consider the possibility that we too can make a thing very small which does what we want—that we can manufacture an object that manoeuvres at that level!” Feynman talked about nanotechnology before the word existed. Feynman dreamed with a technological vision of extreme miniaturization in 1959, several years before the word “chip” became part of our every day life. Extrapolating from known physical laws, Feynman argued it was possible (with, say, an electron beam that could form lines in materials) to write all 25,000 pages of the 1959 edition of the Encyclopedia Britannica in an area the size of a pin head! He calculated that a million such pinheads would amount to an area of about a 35 page pamphlet.

Feynman further added “All of the information which all of mankind has ever recorded in books can be carried in a pamphlet in your hand–and not written in code, but a simple reproduction of the original pictures, engravings and everything else on a small scale with-out loss of resolution.” And that’s just how his talk began. He outlined how, with proper coding, all the world’s books at the time actually could be stored in something the size of a dust speck, with each of the billions of bits in those books requiring a mere 100 atoms to store. How about building computers using wires, transistors, and other components that were that small? “They could make judgments,” Feynman predicted. He discussed about using big tools to make smaller tools suitable for making yet smaller tools, and so on, until researchers had tools sized just right for directly manipulating atoms and molecules.

Feynman further predicted that we will be able to literally place atoms one by one in exactly the arrangement that we want. “Up to now,” he added, “we have been content to dig in the ground to find minerals. We heat them and we do things on a large scale with them, and we hope to get a pure substance with just so much impurity, and so on. But we must always accept some atomic arrangement that nature gives us...I can hardly doubt that when we have some control of the arrangement of things on a small scale we will get an enormously greater range of possible properties that substances can have, and of different things that we can do.” Repeatedly, during this famous lecture, Feynman reminded his audience that he wasn’t joking. “I am not inventing anti-gravity, which is possible someday only if the laws are not what we think,” he said. “I am telling you what could be done if the laws are what we think; we are not doing it simply because we haven’t yet gotten around to it.”


Moore’s Laws:

Gordon Moore, one of the founders of the Intel corporation, came up with two empirical laws to describe the amazing advances in integrated circuit electronics.

            Moore’s first law (usually referred to simply Moore’s law) says that the amount of space required to install a transistor on a chip shrinks by roughly half every 18 months. This means that the spot that could hold one transistor 15 years ago can hold 1000 transistors today. Moore’s first law is good news.

The bad news is Moore’s second law. It is really a corollary to the first, which gloomily predicts that the cost of building a chip manufacturing plant (also called a fabrication line or just fab) doubles with every other chip generation, or roughly every 36 months. The following figure shows Moore’s laws in a graphical way.