nanotechnology

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it is guided by wikipedia and some books

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NANO TECHNOLOGY

NANO TECHNOLOGY

09me84

1.0. INTRODUCTION

Nanotechnologyor nanotech is the study of manipulating matter on anatomicandmolecularscale. Or Nanotechnology is the engineering offunctional systems at the molecular scale. Or 'nanotechnology' refers to the projected ability to construct itemsfrom the bottom up, using techniques and tools being developed today to make complete, high performance products. Generally, nanotechnology deals with developing materials, devices, or other structures possessing at least one dimension sized from 1 to 100nanometres

Nanotechnology is very diverse, ranging from extensions of conventionaldevice physicsto completely new approaches based uponmolecular self-assembly, from developingnew materialswith dimensions on the nanoscale todirect control of matter on the atomic scale. Nanotechnology entails the application of fields of science as diverse assurface science,organic chemistry,molecular biology,semiconductor physics,microfabrication, etc.

There is much debate on the futureimplications of nanotechnology. Nanotechnology may be able to create many new materials and devices with a vast range ofapplications, such as inmedicine,electronics,biomaterialsand energy production. On the other hand, nanotechnology raises many of the same issues as any new technology, including concerns about thetoxicityand environmental impact of nanomaterials, and their potential effects on global economics, as well as speculation about variousdoomsday scenarios. These concerns have led to a debate among advocacy groups and governments on whether specialregulation of nanotechnologyis warranted.

Everything we see around us is made of atoms, the tiny elemental building blocks of matter. From stone, to copper, to bronze, iron, steel, and now silicon, the major technological ages of humankind have been defined by what these atoms can do in huge aggregates, trillions upon trillions of atoms at a time, molded, shaped, and refined as macroscopic objects. Even in our vaunted microelectronics of 1999, in our highest-tech silicon computer chip the smallest feature is a mountain compared to the size of a single atom. The resultant technology of our 20th century is fantastic, but it pales when compared to what will be possible when we learn to build things at the ultimate level of control, one atom at a time.It is argued that through nanotechnology, it has become possible to create functional devices, materials and systems on the 1 to 100 nanometer (one billionth of a meter) length scale. The reasons why nanoscale has become so important are presented.

2.0. HISTORY

Thehistory of nanotechnologytraces the development of the concepts and experimental work falling under the broad category ofnanotechnology. Although nanotechnology is a relatively recent development in scientific research, the development of its central concepts happened over a longer period of time. The emergence of nanotechnology in the 1980s was caused by the convergence of experimental advances such as the invention of thescanning tunneling microscopein 1981 and the discovery offullerenesin 1985, with the elucidation and popularization of a conceptual framework for the goals of nanotechnology beginning with the 1986 publication of the bookEngines of Creation. The field was subject to growing public awareness and controversy in the early 2000s, with prominent debates about both itspotential implicationsas well as the feasibility of the applications envisioned by advocates of molecular nanotechnology, and with governments moving to promote andfund researchinto nanotechnology. The early 2000s also saw the beginnings of commercialapplications of nanotechnology, although these were limited to bulk applications ofnanomaterialsrather than thetransformativeapplications envisioned by the field.

2.0.1. Richard Feynman

The American physicist Richard Feynman lectured, "There's Plenty of Room at the Bottom," at anAmerican Physical Societymeeting atCaltechon December 29, 1959, which is often held to have provided inspiration for the field of nanotechnology. Feynman had described a process by which the ability to manipulate individual atoms and molecules might be developed, using one set of precise tools to build and operate another proportionally smaller set, so on down to the needed scale. In the course of this, he noted, scaling issues would arise from the changing magnitude of various physical phenomena: gravity would become less important, surface tension andVan der Waals attractionwould become more important.

After Feynman's death, scholars studying the historical development of nanotechnology have concluded that his actual role in catalyzing nanotechnology research was limited, based on recollections from many of the people active in the nascent field in the 1980s and 1990s. Chris Toumey, a cultural anthropologist at the University of South Carolina, found that the published versions of Feynmans talk had a negligible influence in the twenty years after it was first published, as measured by citations in the scientific literature, and not much more influence in the decade after the Scanning Tunneling Microscope was invented in 1981. Subsequently, interest in Plenty of Room in the scientific literature greatly increased in the early 1990s. This is probably because the term nanotechnology gained serious attention just before that time, following its use byK. Eric Drexlerin his 1986 book,Engines of Creation: The Coming Era of Nanotechnology, which took the Feynman concept of a billion tiny factories and added the idea that they could make more copies of themselves via computer control instead of control by a human operator; and in a cover article headlined "Nanotechnology",published later that year in a mass-circulation science-oriented magazine,OMNI. Toumeys analysis also includes comments from distinguished scientists in nanotechnology who say that Plenty of Room did not influence their early work, and in fact most of them had not read it until a later date.

These and other developments hint that the retroactive rediscovery of Feynmans Plenty of Room gave nanotechnology a packaged history that provided an early date of December 1959, plus a connection to the charisma and genius of Richard Feynman. Feynman's stature as a Nobel laureate and as an iconic figure in 20th century science surely helped advocates of nanotechnology and provided a valuable intellectual link to the past.

2.0.2. Norio Taniguchi

The Japanese scientist Norio Taniguchi of theTokyo University of Sciencewas the first to use the term "nano-technology" in a 1974 conference, to describe semiconductor processes such as thin film deposition and ion beam milling exhibiting characteristic control on the order of a nanometer. His definition was, "'Nano-technology' mainly consists of the processing of, separation, consolidation, and deformation of materials by one atom or one molecule.

2.0.3. K. Eric Drexler

In the 1980s the idea of nanotechnology as adeterministic, rather thanstochastic, handling of individual atoms and molecules was conceptually explored in depth by K. Eric Drexler , who promoted the technological significance of nano-scale phenomena and devices through speeches and two influential books.

In 1979, Drexler encountered Feynman's provocative 1959 talk "There's Plenty of Room at the Bottom".The term "nanotechnology", which had been coined by Taniguchi in 1974, was unknowingly appropriated by Drexler in his 1986 bookEngines of Creation: The Coming Era of Nanotechnology, which proposed the idea of a nanoscale "assembler" which would be able to build a copy of itself and of other items of arbitrary complexity. He also first published the term "grey goo" to describe what might happen if a hypothetical self-replicating molecular nanotechnology went out of control. Drexler's vision of nanotechnology is often called "Molecular Nanotechnology" (MNT) or "molecular manufacturing," and Drexler at one point proposed the term "zettatech" which never became popular.

His 1991 Ph.D. work at theMIT Media Labwas the first doctoral degree on the topic of molecular nanotechnology and (after some editing) his thesis, "Molecular Machinery and Manufacturing with Applications to Computation,"was published asNanosystems: Molecular Machinery, Manufacturing, and Computation,Foresight Institute which received the Association of American Publishers award for Best Computer Science Book of 1992. Drexler founded thein 1986 with the mission of "Preparing for nanotechnology. Drexler is no longer a member of the Foresight Institute.

3.0. THE MEANING OF NANO TECHNOLOGY

WhenK. Eric Drexlerpopularized the word 'nanotechnology' in the 1980's, he was talking about building machines on the scale of molecules, a few nanometerswidemotors, robot arms, and even whole computers, far smaller than a cell.Drexler spent the next ten years describing and analyzing these incredible devices, and responding to accusations of science fiction.Meanwhile, mundane technology was developing the ability to build simple structures on a molecular scale.As nanotechnology became an accepted concept, the meaning of the word shifted to encompass the simpler kinds of nanometer-scale technology.The U.S.National Nanotechnology Initiativewas created to fund this kind of nanotech: their definition includes anything smaller than 100 nanometers with novel properties.

Much of the work being done today that carries the name 'nanotechnology' is not nanotechnology in the original meaning of the word. Nanotechnology, in its traditional sense, means building things from the bottom up, with atomic precision. This theoretical capability was envisioned as early as 1959 by the renowned physicistRichard Feynman.

I want to build a billion tiny factories, models of each other

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