Diamonds: Women’s Best Friend or a New Advanced Material for Computers?

Diamonds are women’s desire for a long time, Marilyn Monroe said: “Diamonds are forever” and it seems that it’s true. Diamonds, a carbon-based material, not only fascinates women, but also has a great potential to replace silicon in the multi-billion-dollar industry of chip manufacture. Silicon, the most popular material in the electronics industry today has reached its own limits and there is a need to investigate about new forms of materials as it is impossible to sustain Moore’s law balance (“the number of transistors on integrated circuits doubles approximately every two years”) with the existing technology. A known failure mechanism on silicon integrated circuits is “electromigration”, during this phenomenon the flow of atoms comes through the electron flow due to big frequencies and current density. As a result of this situation, a big race in the scientific community is already in progress worldwide in order to create the first diamond-based chip.

Although diamond is not a good conductor of electricity (it can be if it doped with suitable impurities), it is a great thermal conductor (four times higher than copper) suitable to produce high performance chips that will eliminate the use of cooling systems. Chips made by diamond are capable of reaching temperature up to 1000 oC and still functioning, while silicon chips cannot work at temperature up to 150 oC. This property enhances the potential for bigger frequencies and faster signal processing. Furthermore, diamond can handle voltage up around to 200 volts, while silicon can handle only 20 volts. This property makes diamond suitable for power electronics as it can lead to components with smaller size and higher performance (e.g. inverters). Other technical characteristics of diamonds are: wide electronic band gap, low thermal expansion, high resistance to shock, high electrical carrier mobility and broad electromagnetic transmission spectrum, a set of factors that characterize a superb material for the chip industry.

A negative aspect of crystal diamond technology is that natural diamonds are extremely rare and expensive. “De Beers” is a firm which controls the most valuable diamond mines world-wide located in Botswana (South Africa) and owns the monopoly of diamond manufacture. The fact that there is a lack of raw material makes the synthetic diamond industry the perfect solution for chip manufacture supplies. Today synthetic diamond is already used in oil and gas drilling for its extraordinary strength that overcomes every known material on earth. It is also used in laser optics and automotive cutting applications. So there is a well established industry for synthetic diamonds that can support the possible coming of a new diamond technology in the computer industry. Even De Beers invest in synthetic diamonds (!) and has created an individual department that investigates about this technology. The reason is simple, a possible creation of diamond chip can pay back billions of dollars.

A person who supported blending the worlds of diamonds and computers among other computer scientists was pentagon’s advisor John Venables in 1990. John Venables expected that diamond chips could replace the conventional technology in satellites super-computers increasing reliability and speed that is more necessary in this kind of applications and not in personal computers in near future. Very later, Damon Jackson, a researcher on electronic applications, discovered a real way to create circuits on a natural diamond and in collaboration with professor Yogesh Vohra (Birmingham University – Alabama), the last one invented a process to grow synthetic diamonds which are capable of conducting electricity. A possible way to create paths on a diamond which are “friendly” to electricity (good conductors) as suggested by scientists, is using proton beams that target on specific areas and create amorphous carbon or graphite channels which are very conductive. Another try on construction of conductive synthetic diamond comes from “Apollo Diamond” (USA), a firm which has invented a way to create synthetic diamond using CVD (Chemical Vapor Deposition) with a positive and negative charge (p-n) by injecting boron mineral into the diamond lattice. Also, the Japanese government has interested in diamond technology and funds research programs for diamond-based semiconductors since 2003.

This invention, a man-made synthetic diamond layer which conducts electricity in a very sophisticated manner and does not demand complicated cooling systems which consume a lot of energy, it may hold the key to the future evolution of microelectronics and a new generation of computers that will overcome the conventional computer power.