The technique of creating a diamond-graphite elements of electronics

Old news, but I found it online and decided to add.

Staff at the Physics Institute. PN Lebedev Physical Institute (LPI) have developed a technique for producing the finest in diamond graphitized layers. The unique properties of these layers together with technology developed by photolithography to open diamond diamond-graphite structures of great opportunities to build on the basis of their different elements of electronics and optoelectronics.

Part planar line, designed for detecting the UV and X-rays. The basis of the electrode line is a thin graphitic layer arranged in a diamond at a depth of 0.5 m (it is shown in green interference color), the conclusions of the graphitized electrodes are also made to the surface (covered with gold contacts).

   

     Silicon, germanium, gallium arsenide, etc. — The basic materials of modern electronics. Ahead — the development of new materials, development of new technologies. One of the most promising materials is a diamond, it — perfect for all the properties of the material to create electronic components that operate in harsh environments (high temperatures and radiation levels, aggressive chemical environment). Two researchers FIAN — Roman Khmelnitsky and Valery Dravin — under the supervision of the Deputy Director of the Physics Institute, Doctor of Physics and Mathematics Alexei Gippiusa developed a technique for creating a diamond-graphite structures very promising for applications in electronics and optoelectronics. This technique has become one of the practical aspects of long-term studies of microphysics process of graphitization of the diamond — I kind of phase transition in the solid state.
    "A diamond and graphite — is the simplest substances composed of carbon, but with different crystal lattices and various chemical bonds between atoms. As a result, the diamond — hard, graphite — a soft, diamond — clear, graphite — black diamond — insulator and graphite — conductor; chemically diamond — extremely resistant material, graphite is — is etched even weak acids. So, graphite and diamond — it’s fundamentally opposed to all properties of matter, so the transition diamond-graphite can be considered as a reference phase-change type I in the solid state ", — says a senior researcher at the Lebedev Physical Institute, Candidate of Physics and Mathematics Roman Khmelnitsky.
    However, the process of graphitization of the diamond almost never occurs spontaneously, for the transformation of diamond to graphite is necessary to overcome a large energy barrier. One way to overcome this barrier is radiation damage, and the most effective technology — ion implantation.
    "The essence of technology is that ions with energies in the tens and hundreds of keV knock of lattice atoms, and the solid body to restore its crystal structure is subjected to high temperature annealing. However, strongly defective diamond its structure during annealing does not restore, and goes into , in which the atoms, as in graphite, are connected sp2 bonds. As a result, the irradiated area graphitized thin layers are surrounded on all sides of the diamond and thereby secure both chemically and mechanically. By ion implantation can be created in diamond layers with a thickness of several microns to 10 nm at a certain depth, and graphitized layers in a diamond — is a guide to the detention center, wiring or electrode ", — Officer commented LPI.
    But there is in the use of diamond as a material for electronics serious difficulty. The fact is that the basic technology is the modern microelectronics photolithography (the method of applying the material to "shape" the future chips), but the adhesion of the emulsion layer to the diamond is very low. Physicists from the Lebedev Institute in cooperation with specialists from the Institute "Pulsar" was able to overcome the technological difficulties, and photolithography technology across the diamond to get a life.
    "The first thing we did was sprayed onto the metal diamond, but not all, and the only one that has a good contact with the carbon. Thus, photolithography is not directly across the diamond and the metal, which is used as a mask. Attached to Technology Ion implantation is necessary to use two-and three-layer metal coatings ", — explains the essence of photolithography technology across the diamond Roman Khmelnitsky.

 

Until recently the diamond was not considered as a serious candidate for electronic applications. First, because of the high cost of natural diamonds, and secondly, because of the small sample available, and third, because of the poor quality of the material. It is only in connection with the development of technologies for growing synthetic diamonds of good quality, with the advent of the prospects for creating diamond plates relatively large area (now trying to make a plate of 2 inches), and thanks to working out specific methods "to curb the" diamond in the practical purposes (as described above) in this crystalline form of carbon there is a good chance to find a niche in electronics.
    / 22.04.2010 / According to the materials ANI "LPI-Inform"

Like this post? Please share to your friends: