Researchers at the University of Wisconsin in Madison, United States, and at the Argonne Center for Nanomaterials at the US Department of Energy, have been able to develop self-guided graphene strips on the surface of a semi-conductor monomer semiconductor germanium, which has been widely used as a substitute for silicon in the manufacture of transistors and other electronic devices Depends on its work on semiconductors.
The invention of these bands will revolutionize the circuitry. The trajectories of the graphite nanoparticles can be controlled over the surface of semiconductor germanium crystal
Thanks to the properties of graphene electronic, scientists have been able to test the theories associated with particle accelerators, and the difficulty in using the transistor because of the occurrence between metals and semiconductors, and in 2010, scientists succeeded in the production of graphene, it was natural to use carbon replace silicon in the next generation of computers and electronics Minute, faster and more efficient
Characteristics of electronic graphene
The properties of graphene electronics are of interest to scientists, providing them with a ground to test strange theories in the field of quantum physics associated with particle accelerators.
Graphene is the strongest and hardest proven material to date. Its strength is 300 times greater than steel, 40 times more diamond, and its efficiency as a heat and electricity conductor is 1,000,000 times better than copper, a high density two-dimensional transparent carbon It is characterized by super properties and carbon atoms similar to the densely populated bee houses. Perhaps the most prominent advantages are the speed of its unusual electrons, which can reach 44,000 cm2 / sf, and its carbon atoms form covalent bonds at one level.
When graphene is converted into a spherical shape, we get balls. If we fold into cylindrical shapes we get the carbon nanotubes. By placing enough graphene slices on top of each other we get graphite, and graphene is cut into small pieces that produce nanotubes.
Graphene is a key in the manufacture of touch screens, luminescent panels and photovoltaic cells. It can also be used in the manufacture of high-flexibility and folding gas and electronics sensors, and thus in the manufacture of some parts of airplanes and satellites. It is also used in the development of plastics, The addition of some of them by a simple rate, increases plastic flexibility, enhances its ability to withstand heat, and increases its efficiency in the delivery of electricity
Most applications to use graphene electronics
And the most applications that will soon use electric batteries, with the ability to increase their effectiveness, and the graphene powder is better than carbon nanotubes, because of the cheap price.
“Some researchers wanted to manufacture transistors from materials other than carbon nanotubes, and the obstacle to their desire was to expand the size of the tubes in all directions of all kinds. The new innovation is focused on the ability of researchers to scale up these tubes through circuit paths,” said Brian Curry of the Argon Center. Which depend on all the organs in its work ».
Researchers at the University of Wisconsin used chemical vapor deposition to scale the size of graphene nanoparticles over germanium crystals. During the process, a mixture of methane, hydrogen and argon gas is passed into an electric furnace designed to collect and purify inorganic compounds. Methane gas inside the furnace is dissolved into carbon atoms The germanium surface forms a homogeneous layer of graphene. After adjusting the room settings, the researchers were able to control the material completely.
“What we discovered is that when graphene is activated above germanium, the nanotubes are automatically made up of soft interchangeable edges, and the strips can be very narrow, but their lengths are very extended,” says Michael Arnold, associate professor of materials and engineering at the University of Wisconsin at Madison. Then, we get what we want from the properties of these tapes automatically using the new technology ».
What is known about electrons of carbon atoms in graphene
Carbon electrons in graphene are known to move above the surface at the speed of light without interfering. Thanks to this speed, electronic devices can be manufactured at high speed and provide more energy at the same time, according to Arnold.
“The nanotechnology department has tremendous potential,” said Giesinger. “The department is not only designed to work on all kinds of materials, from metals to oxides, but we can also The material is supplied with special specifications, synthesized, and increased in size ».
Using the microscopic scanning microscope, which uses electrons instead of light or naked eye, to see the properties of a sample of the material, the researchers confirmed the growing size of graphene strips over germanium. The data they collected on electron fingerprints allowed researchers to draw images of the dimensions and trends of matter, They were able to determine its structure and the extent of dispersion of electrons.
The characteristic electronic properties of graphene
“We are looking at the basic physical properties of the morphological properties of graphene,” Kirali said. “What surprised us was that nanotubes were enlarged and stretched in specific directions over a particular side of germanium crystallization, and not on either side.
To take advantage of the new technology in the manufacture of electronic devices, semiconductor industries focus on three surfaces of germanium crystallization. These three surfaces are visualized according to the coordinates X, Y, Z, where individual atoms are connected to each other in a gridlike form of diamond composition. After each of the crystal surfaces 1,1,1, with different axes of 1,1,0, 0.
A previous study showed the ability of graphene chips to increase their size over the germanium crystal surfaces 1,1,1,1,0, and that was the first time any study had been shown, extending the size of graphene strips above the surface 1.0,0.
As the researchers develop their research, they are also studying the cause of the expansion of self-guided graphene nanoparticles above surface 1.0,0 and determining whether a particular interaction between graphene and germanium can play a role.
There is no doubt that the proliferation of electronic devices in the present era is the result of the development of semiconductor materials chips that are exceptional in their form of vacuum, and enabled these chips scientists to manufacture integrated circuits effective, because each transistor of billions of transistors that make up the circuits behave And differences in performance between semiconductor devices are found to be very small, and far less than any differences in performance between devices based on any other technology
The reduction of transistors over the past few years has attracted researchers’ attention to the issue of the minimum size of transistors, electronic devices made with a specific thickness on the atomic scale. Researchers at research laboratories have already reached this threshold by producing experimental primers of thin semiconductor materials, , But these integrated circuits can not be manufactured using these devices, unless scientists find out how to extend the atomic material in a symmetrical manner over large surface areas. Scientists were able to achieve that symmetric expansion on a chip scale, the size of square centimeters, and was one of the most promising chip categories of two-dimensional semiconductors.
Although the results achieved by researchers are a big leap forward in the research of thin semiconductors with the thickness of the atomic scale, but there are problems that stand in front of scientists, and must be solved before the application of the results in practice, such problems, for example, ideal expansion conditions that It requires a temperature of 550 ° C to be maintained for 26 hours, which is a very high temperature and therefore can not be used in the manufacture of flexible plastic layers currently available, so another process is needed at low temperatures.
The two-dimensional semiconductor developed by the researchers opens up great opportunities for the manufacture of new and sophisticated electrical devices and circuits that are more efficient than traditional field effect transistors