Dieter Gruen - Diamond Films

Diamond Films

Gruen conceived, starting in 1991, a radically new method for making diamond films by a chemical vapor deposition (CVD) process that does not require the use of atomic hydrogen in contradistinction to traditional CVD methods that do. By fragmenting fullerene molecules (C₆₀) in noble-gas microwave discharges, he was able to produce the carbon dimer, C2, a new nucleation and growth species, which condenses to form nanocrystalline diamond films. This unique material has been shown by Gruen and his colleagues to be extraordinarily useful in a number of tribological, microelectronic, and telecommunication applications, many of which will lead to substantial energy savings.

Certain classes of meteorites (carbonaceous chondrites) also contain substantial amounts of presolar nanocrystalline diamond grains. It is possible that the carbon dimmer nucleation and growth mechanism experimentally and theoretically established by Gruen and his colleagues was also operative in the presolar nebula and thus was involved in the formation of the diamond grains found in meteorites. Indeed, the cosmic synthesis of nanocrystalline diamond may be occurring today in so-called protoplanetary nebulae, a relatively brief stage in the evolution of red-giant stars, which our own sun will enter in the far distant future.