Tools and techniques

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Read and translate the text.

Tools and techniques

Unit X

1. Practice the following words:

Tunneling ['tΛnliŋ], acoustic [ə'ku:stik], technique [tek'ni:k], ultraviolet [Λltrə'vaiəlit], vapor ['veipə].

2. Study the vocabulary list:

probe – зонд

to launch – запускать, начинать

scanning probe microscopy – сканирующая зондовая микроскопия

acoustic – акустический

coworker – сотрудник

to implement – вовлекать, внедрять

velocity – скорость

X-ray – рентген

ultraviolet – ультрафиолетовый

vapor – пар, газ

epitaxy – эпитаксия

confocal – cофокусный

There are several important modern developments. The atomic force microscope (AFM) and the Scanning Tunneling Microscope (STM) are two early versions of scanning probes that launched nanotechnology. There are other types of scanning probe microscopy, all flowing from the ideas of the scanning confocal microscope developed by Marvin Minsky in 1961 and the scanning acoustic microscope (SAM) developed by Calvin Quate and coworkers in the 1970s, that made it possible to see structures at the nanoscale. The tip of a scanning probe can also be used to manipulate nanostructures (a process called positional assembly). Feature-oriented scanning-positioning methodology suggested by Rostislav Lapshin appears to be a promising way to implement these nanomanipulations in automatic mode. However, this is still a slow process because of low scanning velocity of the microscope. Various techniques of nanolithography such as optical lithography, X-ray lithography dip pen nanolithography, electron beam lithography or nanoimprint lithography were also developed. Lithography is a top-down fabrication technique where a bulk material is reduced in size to nanoscale pattern.

Another group of nanotechnological techniques include those used for fabrication of nanowires, those used in semiconductor fabrication such as deep ultraviolet lithography, electron beam lithography, focused ion beam machining, nanoimprint lithography, atomic layer deposition, and molecular vapor deposition, and further including molecular self-assembly techniques such as those employing di-block copolymers. However, all of these techniques preceded the nanotech era, and are extensions in the development of scientific advancements rather than techniques which were devised with the sole purpose of creating nanotechnology and which were results of nanotechnology research.

The top-down approach anticipates nanodevices that must be built piece by piece in stages, much as manufactured items are made. Scanning probe microscopy is an important technique both for characterization and synthesis of nanomaterials. Atomic force microscopes and scanning tunneling microscopes can be used to look at surfaces and to move atoms around. By designing different tips for these microscopes, they can be used for carving out structures on surfaces and to help guide self-assembling structures. By using, for example, feature-oriented scanning-positioning approach, atoms can be moved around on a surface with scanning probe microscopy techniques. At present, it is expensive and time-consuming for mass production but very suitable for laboratory experimentation.

In contrast, bottom-up techniques build or grow larger structures atom by atom or molecule by molecule. These techniques include chemical synthesis, self-assembly and positional assembly. Dual polarisation interferometry is one tool suitible for characterisation of self assembled thin films. Another variation of the bottom-up approach is molecular beam epitaxy or MBE. Researchers at Bell Telephone Laboratories like John R. Arthur. Alfred Y. Cho, and Art C. Gossard developed and implemented MBE as a research tool in the late 1960s and 1970s. Samples made by MBE were key to the discovery of the fractional quantum Hall effect for which the 1998 Nobel Prize in Physics was awarded. MBE allows scientists to lay down atomically precise layers of atoms and, in the process, build up complex structures. Important for research on semiconductors, MBE is also widely used to make samples and devices for the newly emerging field of spintronics.

However, new therapeutic products, based on responsive nanomaterials, such as the ultradeformable, stress-sensitive Transfersome vesicles, are under development and already approved for human use in some countries.

4. Compare two columns of words and find Russian equivalents (from the right column) to the following English words (from the left one):

1.Сканирующие зонды	a) scanning acoustic microscope
2. запускать нанотехнологию	b) various techniques of nanolithography
3. сканирующий акустический микроскоп	c) scanning probes
4. управлять наноструктурами	d) to launch nanotechnology
5. из-за медленной сканирующей скорости микроскопа	e)an important technique for characterization and synthesis of nanomaterials.
6. уменьшать материалы в размере до образца наноуровня	f) because of low scanning velocity of the microscope
7. важный технологический прием для описания и синтеза наноматериалов	g) self-assembling structures
8. различные технологические приемы нанолитографии	h) to reduce materials in size to nanoscale pattern
9. изготовление нанопроводов	i) to manipulate nanostructures
10. перемещать атом по поверхности	j) fabrication of nanowires
11. самоорганизация структур	k) to move atoms on the surface

6. Arrange synonyms in pairs:

To include	to alter
to operate	to explore
to investigate	to manipulate
matter	outcome
production	manufacturing
plausible	question
result	possible
to change	to incorporate