It was common knowledge that developed countries in the world, such as the United States, Japan, Australia, Canada and European countries, as well as some Asian countries, like Singapore, China, and Korea enterprising middle-jealous develop a new branch of the popular technology called Nanotechnology. Billions of dollars of funds began to be disbursed in these countries, in various fields of research. Everything is vying to use keywords Nanotechnology. Actually what is nanotechnology? And why do so many researchers in various countries vying to enter the field this one? How luaskah scope? Why this happened just a few years nanotechnology boom?
As the name implies, nanotechnology is technology on the scale of nanometers, or billionths of meters. To be able to imagine the dimension of nanometers, we can take example from our own bodies.
A strand of human hair has a diameter of approximately 50 micrometers. One micrometer is one-thousandth of a millimeter own. And one millimeter is the size of the smallest unit of length on a ruler wrote 30 cm, typical school children. And one nanometer is one-thousandth of micrometers, or roughly equal to the diameter of our hair has been cut 50,000 times! As another comparison, the size of our red blood cells is about 20 micro meters, and abdominal bacterial cell is 2 micro-meters. The protein has a size of several tens of nanometers.
From the viewpoint of the size of the top down (top down) like it, nanotechnology is important in the world because of human engineering seeks to integrate a function or work in a smaller size scale and smaller. Why? People say, "small is beautiful (small is beautiful)", but, of course integrate a function of machines or tools in a smaller size not only means memperindahnya but also means to reduce the energy required by a work function and thus the speed up the process and mempermurah cost jobs. As an example of our easy to understand is what happens in the world of computers and microprocessors. Factories microprocessors such as IBM, Intel and Motorola continue to strive to higher levels of integration mikroprosesornya.
Approximately ten to fifteen years ago, the distance between the gate (gate) MOS (metal oxide semiconductor) is 0.75 m, and the level of integration in the 5P 80 386 to 80 486 is approximately 100,000 to 1 million transistors on a chip. But, on the Pentium IV, processing technology, IC (integrated circuit) which has been used successfully to reduce the distance between the gate to only 0.125 m and reached the level of integration up to 100 million transistors on a chip chip.
Smaller distance between the gate means increasingly little time required to travel an electron (which means faster switching rate) and will also mean little more processor power required. More than that, the more functions that can be integrated in the processor, such as a built-in multimedia, voice processing, and so forth.
In addition, this IC processing technology began to be used also to integrate the functions of mechanical and electrical for the engine, sensors or actuators on the size of milli, micro, up to nanometers. Micro structure that integrates the mechanical and electrical function is usually called Micro Electro Mechanical System (MEMS). For example, MEMS technology allows the creation of an array of pressure sensors so small in size (Figure 1) as to be placed anywhere in a building structure or machine, for example.
However, if nanotechnology is only struggling with IC and microelectronics engineering are then applied also to mikromekanika? If only so if the need forthis terminology is thus heralded the end-; days?
It turns out that nanotechnology is currently booming not only associated with conventional engineering top-down IC or MEMS. All this stems from a scientific speech Nobel laureate, Richard Feynman in 1959, entitled "'There is plenty room at the bottom" (There's plenty of room below), which is now widely cited nanotechnology enthusiasts.
At that Feynman said, it is possible (at least when it was still in the dream) to create a machine so small in size, which can then be used to manipulate materials on the scale of that size. In fact, it was Feynman states also, if a physicist given the "engine" right to manipulate atoms and placed at appropriate places, then he could theoretically make any compound or molecule, of course, a stable energy (stable = minimum energy level .)
Such systems, though not at the atomic level, at least has existed in nature, as has been written also by K. Eric Drexler in the landmark papers in 1981, and introduces the term molecular manufacturing (molecular manufacturing). In her paper, the Drexler gave several examples, how nanometer-sized machines already exist in nature and how they have been involved in the preparation of molecules and information in living cells. For example, the ribosomes that make up the amino acids one by one based on RNA, for memfabrikasi protein, then the genetic system (DNA polymerase enzymes, RNA polymerase, etc.) that store and process genetic information, flagella (a kind of structure 'hairs') on bacteria as its driving force, and so forth.
The ability to manipulate materials at nanometer scale is important, because at this size scale of material begin to form certain properties based on structure. On a smaller level, atomic level (Angstrom scale), which is owned properties is the nature of the atom itself. When the atoms begin to join each other and develop a specific molecular structure, nature would be different according to the structure. For example, atomic carbon (C), which when arranged in a tetrahedron three-dimensional structure will form a diamond is hard, but when arranged in two-dimensional hexagonal structure and form layers, so that we found was that of graphite (pencil raw materials) of fragile.
Nanotechnology is aimed at developing molecular manufacturing methods (eg in the form of 'engine' of nanometer-sized) that can do the preparation of the component atoms or molecules on a regular basis and controlled to form the desired structure. Model material fabrication bottom to top (bottom-up) as opposed to conventional top-down technology like this will allow very precise control of material properties that form (ie free of defect / defects).
Besides reducing the incidence of waste during fabrication because only atoms / molecules to be used are manipulated (different from top-down methods that often lead to waste due to unused material), and of course the possibility of saving energy also means saving costs. Systems such as photosynthesis in plants is an example of molecular manufacturing system with high energy efficiency.
The problem then, how the component atoms or molecules can be prepared? As well as the approach of ribosomes in the cell, Drexler proposed the making of "arm-arm" robotic and nano-sized components of other machinery that allows for the withdrawal fabrication processes on a macro level: sorting of materials, energy conversion, material placement, etc..
This method is called Mekanosintesis, doing chemical synthesis mechanically. Some nano-size structure of the machine (which was formed from several thousand to millions of atoms) have been successfully simulated with the computer, which means mathematically and physically possible to be made. An example is the wall of the room containing the pump rotor material and selectively choose which functions atomic neon (Ne) to be ready for use on the next process (Figure 2).
The next problem, if such a structure is "possible" (read: stable thermodynamic) to be made, how the process to make the initial structures to be used as a machine for the fabrication of nano-machines next? And from what was originally the driving energy?
Some proposed alternatives have begun to try to solve the first problem. Nadrian Seeman tried to make these basic structures of molecules of DNA (deoxyribonucleic acid, the basic compound gene) by relying on the nature of self-raft (self-assembly) of DNA, which binds to Thymin Adenine and Guanine binds with Cytosin.
By synthesizing DNA with specific sequence, Seeman managed to create basic shapes and devices nanomekanik DNA cube. Other researchers at NASA Ames Research Center to simulate the use of Carbon Nano Tube (a tubular structure of carbon atoms are synthesized nanometer dimension with the principle of self-assemble from carbon, the use of certain metal catalysts) to form the gear and the crankshaft. The structure of gear or shaft can be made from carbon nanotubes with a certain chemical reaction to "put the" wheel-shaped cluster of chemical molecules (eg benzene) around the tube (Figure 3).
Another way to arrange the components of an atom or molecule at this early stage is to use nanotechnology instruments, such as the Atomic Force Microscope (Atomic Force Microscope, AFM), and Breakthrough Scanning Electron Microscope (Scanning Tunneling Microscope, STM). The second basic principle is like moving the microscope "hand touch" in xy coordinates, while maintaining the distance (z coordinate) between the "hand touch" with the sample being studied (Figure 4).
Called the "hand touch" because it's microscopes are no longer using light as an imaging tool due to the limited light on the nanometer scale (the effect of light diffraction). AFM to detect non-covalent forces (non-chemical bonds, such as electrostatic forces and Van der Waals force) between the samples with "hand touch", while the electrons from the STM detects breakthrough "hand touch" which penetrates the sample and received by a detector below the sample. At first, these instruments are limited only used for characterization or 'imaging' sample. But, lately, starting also be used to manipulate molecules and atoms. By changing the current major breakthrough in STM for example, we can take O atoms and reacting with CO molecules to form a molecule of CO2 and everything is done with single molecule precision. In ordinary chemical reactions, it takes quite a lot of molecular components that react to possible, statistically, the "collision" between these molecules.
With regard to the problem of energy supply structure at the nanoscale machines, Prof. Montemagno at the University of California at Los Angeles has successfully tried to use bio-natural nanomotor F1-ATPase to drive the propellers are made with MEMS technology. Bernard Yurke of Bell Labs. using DNA to try to make a nano-motor.
Another possible alternative is to combine top-down nanotechnology MEMS with bottom-up nanotechnology. Electric motors and generators of energy (eg battery thin layer) on the micrometer scale with MEMS technology has been widely reported. Next live transmits motion from the motor to the structure of the "arm" robot on a smaller scale - nanometers.
Dream nanotechnology to manipulate the material with the same level of flexibility that has been achieved with humans in manipulating data with information technology, it may still seem far away and still a lot of homework to do. However, in its development is still too young now, nanotechnology has provided a new color in other areas.
Application of nanotechnology in analytical biotechnology such as allowing new methods are much more sensitive and stable than conventional methods. The development of MEMS, which even depart from the conventional IC technologies, still in progress so rapidly, with new applications in optics (appears MOEMS - Micro Optical Electro Mechanical Systems), integrated sensor systems, non-wire, and also in the application of RF (Radio Frequency)-MEMS. On the development of nanotechnology is so felt, how the background science and technology of multi-discipline is needed: the mathematical modeling, physics for understanding the phenomena of style and energy, chemical (inorganic and organic) to understanding the nature of the material, and biology to learning-system engineering systems in living organisms.
In addition, creativity and the creation of high power is needed to discover breakthrough techniques and new methods, and applications that fit. Of course, moral virtue and religion still needed for the application of this technology does not actually harm the survival of mankind.
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