Technology Nanotechnology

Discussion in 'Technology' started by mscbkc070904, Mar 21, 2005.

  1. mscbkc070904

    mscbkc070904 Premium Member

    I decide to make a thread on nanotech, hence I wasnt to sure of what it is in all aspect. So here is the defintion of nanotech

    Definition: The development and use of devices that have a size of only a few nanometres. Research has been carried out into very small components, many of which depend on quantum effects and may involve movement of a very small number of electrons in their action. Such devices would act faster than larger components. Considerable interest has been shown in the production of structures on a molecular level by suitable sequences of chemical reactions or lithographic techniques. It is also possible to manipulate individual atoms on surfaces using a variant of the atomic force microscope to make, for example, high density data storage devices.
     
  2. mscbkc070904

    mscbkc070904 Premium Member

    History

    Ever since the days of the Greeks and Democritus, man has believed that when dividing up matter we will eventually reach a point where we can divide no more because we have found the essential unit of matter, then referred to as the atom. Through experimentation man has discovered the basic composition of all matter in that it is composed of 108 types of atoms, along with their various isotopes. We have since discovered even smaller "fundamental particles" such as bosons, muons, quarks, leptons, etc., which fit into three different families. However, we will disregard those developments and even smaller divisions of matter since it is the characteristics of atoms and their effect on fabrication which we hope to look at. These smaller divisions will be touched on in the "Future" section but otherwise they are left to the reader's exploration.

    Atomic Scale Thinking

    We will start out history of nanotechnology by first starting with atoms and the advancement in physics over the past century. The story has many cloudy beginnings, but we might trace one root to Joseph Proust in 1799 when he discovered that chemicals tended to combine in particular ratios which later came to be knows as their molecular formulas such as H20. Next came the interesting observation of Brownian motion in 1827 by which all particles at the microscopic level have an inherent energy that causes them to constantly vibrate. Einstein then articulated a theory in 1905 of this thermal energy based on heat and how it would cause particles to naturally distribute in a certain volume. This Brownian motion is part of the reason why atoms have been so elusive and why some scientists have often argued that we could never individually control atoms.

    Developments in Biology

    Discovering DNA has been one of the landmark accomplishments of science in the 20th century. It was initially discovered by Watson and Crick in 1953 as they viewed it through a microscope. With the rapid developments in science, by 1970 scientists had already discovered many of the basic properties and had begun to manipulate DNA by cutting, splicing, and recombining it with the help of enzymes and ligases. A few years later came a machine that could actually produce any desired DNA sequence which was then programmed into a program. The next step was reprogramming bacteria and other organisms to produce desired proteins, and already we were into the era of using DNA on that nanometer scale for manufacturing processes.

    When pondering the constructions and design of nano-scale, atomic-sized structures, scientists and futurists always naturally think of DNA, which it has perfected through millennia of evolution. If science has already demonstrated to us that replication and manufacturing can exist and in fact thrive at that level, then what's to stop us from either imitating it or creating something even better?

    Feynman's Speech

    Contributions in the fields of Physics, Biology, and Chemistry have all brought together the information necessary to conceptualize and pursue Nanotechnology. However, it was Richard P. Feynman, later Nobel Prize Winner in Physics, who gave a dinner talk in 1959 for the American Physical Society that seems to have started it all, or at least made the idea tangible. His speech was entitled "There's Plenty of Room at the Bottom" and postulated the idea you could write the entire Encyclopedia Britannica on the head of a pin! This would require text to be text be 1/25000th of its current size. He also talked about somehow manipulating individual atoms, about miniaturizing the computer, and developing better techniques and machinery for viewing these tiniest of details. He then ended his speech with the announcement of two prizes as incentives for others to go try out what they could accomplish in this realm. One $1000 prize was for an electric motor that could only be 1/64th of an inch cubed. The other was for the first person who could shrink replicate a page of a book at 1/25000th scale so that it could be read by an electron microscope. Both prizes were claimed, in 1960 and 1985, respectively. Pictures are included on pages 75 and 147 of Nano.
     
  3. mscbkc070904

    mscbkc070904 Premium Member

    Current Methods of Fabrication and Design

    Lithography

    Current technology using top-down fabrication techniques has many steps, but the most precise step involves a stream of particles or energy which is used to etch the surface of a device into a certain pattern. This smallest step which determines the smallest component of a design is referred to as the "critical dimension." Currently Optical Lithography is still the leading operation used, and involves a focused beam of light produced by Krypton-Fluoride (KrF). It has been found that the size of the features that can be etched into the surface of the device is limited most significantly by the wavelength of the light being used. KrF has a wavelength of 248 nanometers and can produce a smallest dimension of around 250 nm, basically the same size as the wavelength. Other possible light emission sources would be Argon Fluoride (ArF) with a wavelength of 193nm, Fluoride Gas (F2) with a wavelength of 157nm, and Argon Gas(Ar2) with a wavelength of 126 nm.

    It was expected long ago that optical lithography would hit some physical boundary and that it would no longer be developed for smaller and even smaller applications. For this reason several alternate possibilities have been researched, but none of them are being used for mainstream manufacturing until optical lithography hits that wall. It will always be easier for companies to improve and modify their current machinery rather than investing in a whole new technology. These new technologies are E-beam lithography (which utilizes a beam of electrons), X-ray lithography (using x-rays), Extreme Ultraviolet Lithography (similar to x-ray but renamed), and Ion Beam Lithography.

    Molecular Design and Advancements

    In order to approach nanoproduction from a bottom-up approach, there are several developmental goals which must be accomplished. First, we must be able to pick up and place individual atoms in a pattern. This was done first in the IBM labs in 1989 and was quickly followed by other scientists around the world. However, these first atoms were noble-gases, the group of atoms that are non-reactive and are not be attracted to each other. Real devices would be made of atoms that would be attracted and would bond together. I am not sure how far they have gotten in actually constructing molecules but I'm sure advancements are still being made in this direction.

    The other task being accomplished is the design of what molecules and structures would be useful tools. With the increasingly capable computers that are available, a very complex model such as the interaction of molecules can modeled and predicted. The decades of hard work by physicists is paying off in that respect because we have numerical models for basically every way that atoms interact, both classically and in the quantum mechanics model. Many websites on the Links page showcase these designs, but the producer and forerunner in this area is the Institute for Molecular Manufacturing (IMM).

    Self Assembly

    The use of self-assembly methods is another way of producing nano-thickness devices, utilizing the structure and properties of nature. This is a hopeful area in further development because it does not require any multi-million dollar equipment. In the particular method I learned in lab this semester, called Ionically Self-Assembled Monolayers (ISAM), certain polymer solutions are produced and then glass slides are dipped from one beaker into another and back and forth. The glass has a negative charge to it and will therefore attract ions from the positive ion solution. Within a period of three minutes (wow!), no more polymers are attaching to the surface and the slide can be rinsed and placed into the bath of negative ions. Thus a large number of layers can be deposited onto a slide. This approach has already been used to create flexible diodes and even solar cells, although about a magnitude of efficiency behind the current silicon technology.

    Other techniques involve the creation of nanotubes, or elongated Bucky Balls, and then place additional conductive ions within them. This method is currently being developed to create nano-transistors.
     
  4. mscbkc070904

    mscbkc070904 Premium Member

    What is the future of Nanotechnology?

    Whether Nanotechnology will actually develop as a unique scientific discipline or area of commercial opportunity is still uncertain. There will continue to be materials and research for which analysis and evaluation must be at the nanoscale range. This is not new. However, robotic or mechanical devices operating at the nanoscale will probably not be commercialized in the near term.

    We are actively involved in pursuing promising research to develop equipment and procedures to manipulate single atoms or molecules with the goal of establishing a new class of man-made atomic structures constructed one molecule at a time. Similar technology and processes will also eventually find applications in the medical and pharmaceutical industries. Since computational speed and power are directly related to the operational scale of the processors, nanotechnology will certainly be an important aspect in the future of computer processing technology. We also believe other promising areas include environmental, energy and space-based technologies.

    What are the safety, hazard and public policy issues with Nanotechnology?

    Numerous articles have recently been published warning of the dangers presented by unregulated nanotechnologies. The most fantastic of which is the threat of Gray Goo, a hypothesized substance resulting from the runaway dissolution of the earth by self-replicating nanobots. While many of these concerns seem less science than science fiction, the very scale range of these materials do present safety and environmental issues that should be addressed responsibly by industry at least in the same manner as fine particulate materials are currently handled under existing health and safety guidelines.
     
  5. mscbkc070904

    mscbkc070904 Premium Member

    What Does the Future Hold?

    Short Term - Smaller, Faster

    Technologies built from the nanometer scale up will have little or no impurities or inaccuracies. Molecular bonds are some of the strongest we know of. When each atom is precisely put in place, there should be no unbonded atoms or dangling structures to contribute weaknesses to the system. Additionally, when each atom is put in place there should be more tolerance for placement since the molecules at the atom's designated position should naturally draw it in, based on basic physics. (Drexler, 64) This purity would be ideal for computing industries which are constantly in search of even purer production methods of Silicone, already achieving grades of 99.999% purity.

    Another advantage of nanotechnology is its use as a storage media. Instead of a whole blob of matter storing a bit of information via an electric charge, there are other methods with scientists have envisioned. For instance, what if you could create a design on a surface using two types of atoms. Each atom would be either Element 1 or Element 0, and in an ordered fashion can store data. For instance, scientists have envisioned doing this on a surface of diamond. Other scientists envision using far smaller atomic characteristics as the storage medium. What if we could use the position of electrons in an atom? Or what if we could use the spin of an electron, which only has two directions? It seems like the possibilities are endless.

    Mid-Range - Automated Processes

    Once we are able to develop independent nanodevices and then are able to program them, we will be able to utilize them in a slew of biological applications. In the medical industry, devices could be released into the bloodstream where it is hoped they will serve as "cellular repairmen," repairing damaged tissue at the atomic level. In research much more detailed information could be collected about cellular processes.

    Long Term - Macro-Scale Fabrication

    The Holy Grail of nano-fabrication is the ability to build macroscopic products from the ground up. After all, if you can build little things, then why can't you just build and build and build until you have something that can actually be seen by the naked eye, or even used by people as a standard product.

    What impact would this have for society, however? Imagine a world in which you punch a few keys on a touch screen and in minutes a food replicator creates a nutritious meal. Imagine having clothing actually produced for you by the labor of these little tiny machines, without even lifting a finger. Imagine the vast amount of work that people would not have to do. Life would be so much better, or would it? This idea was is very similar to that visualized when robots became a hot topic of conversation. What would happen to people when robots began providing for all of our physical needs? Ethical controversy abounds and in the end a middle ground was struck wherein certain jobs are still restricted to solely human labor, and in other ways human kind has benefited tremendously from their inception.

    Here is one man's view of the future: http://www.nickbostrom.com/2050/world.html
     
  6. mscbkc070904

    mscbkc070904 Premium Member

  7. sardion2000

    sardion2000 Member

    Ah a subject I know something about :) I'll put in some links you missed, alot of good stuff out there but also alot of fluff(ahem Smalltimes is "fluff" as is NewScientist due to lack of details)

    http://nanobot.blogspot.com/ Former Small Times editor Howard Lovy's Nanobot, when he got forced out that is when I lost respect for smalltimes :dn:

    http://www.softmachines.org/wordpress/index.php -- A blog written by a Molecular Biologist(I believe that is what he is not sure though)

    http://www.nanalyze.com/forums/active.asp -- Web Forum dealing with investing in Nanotechnology Companies

    http://www.betterhumans.com/

    http://www.technovelgy.com/ -- Not exactly Nanotech but expect more and more nanotech appliances to appear as they get invented really cool site IMO

    http://www.azonano.com/nanotechnology.asp
     
  8. _Angel_1991

    _Angel_1991 Premium Member

    OH NO!!! NANOTECH!!!:lol:
    Seriously, nanotech is cool, but the problems that can crop up include "Big Brother" type spying and etc. Let's hope new laws are put into place that will counteract these dangers.
     
  9. bodebliss

    bodebliss The Zoc-La of Kromm-B Premium Member