NanotechnologyAjay Di sharma
Nanotechnology is the engineering method in which fully functioning devices are manufactured at the molecular scale. Through this method, the devices that are manufactured will be having higher performance than the conventional ones. The items will be constructed from the bottom up with the help of high performance techniques and tools.
Undoubtedly, nanotechnology is going to be the future, as studies are going on in diversifying the technology from materials with dimensions in nano scale to materials in dimensions of atomic scale. Some new methods like molecular self-assembly have been developed to make this possible. There may be a future when all the common basic needs like food, shelter and even costly diamonds will be made by nanorobots.
When talking about the basics of nanotechnology, it is important to first know how small ‘nano’ actually is. Let us compare different units with respect to metres.
1 centimetre – 1,00th of a metre
1 millimetre – 1,000th of a metre
1 micrometer – 1,000,000th of a metre
1 nanometre – 1,000,000,000th of a metre
This clearly shows how small a nano is. It is even smaller than the wavelength of visible light and a hundred-thousandth the width of a human hair. But it is still small when compared to the atomic scale.
Atomic diameter – 0.1 nanometre – 1,000,000,000,0th of a metre.
The usual scale of some common man made materials are compared with nano devices. Take a look in the figure given below.
The History of Nanotechnology
The first talk on nanotechnology was given in the year 1959 by a physicist named Richard Feynman. He talked about a process in which the individual atoms and molecules
Feynman described a process by in which, by using a set of precise tools you could develop individual atoms and molecules. Another set of tools would also be needed to operate another proportionally smaller set, and so on down to the needed scale. Later this method was clearly defined by a science professor at the Tokyo University of Science called Norio Taniguchi. The technology became really famous during the 1980’s and was promoted to big depths by Dr. K. Eric Drexler through his books like “Engines of Creation: The Coming Era of Nanotechnology” and “Nanosystems: Molecular Machinery, Manufacturing, and Computation.”
The main step in the development of nanotechnology was the invention of cluster science and scanning tunneling microscope (STM) in the 1980’s. Through them carbon nanotubes and fullerenes were developed in 1985. Then came developments in synthesis and properties of semiconductor nanocrystals. The greatest invention which led to the foundation of the United States National Nanotechnology was the Atomic Force Microscope (AFM or SFM).
Nanotechnology – Concept
When comparing the size of a nano device to typical carbon-carbon bond lengths, it is in the range between 0.12–0.15 nanometres. Even the smallest cellular life-forms, the bacteria of the genus Mycoplasma, are around 200 nm in length. Thus, to make devices in such a small size two concepts are adopted. They are
- Bottom-up Concept
- Top-down Concept