SYNTHESIS OF DIAMOND FROM METHANE AND NITROGEN MIXTURE

We have found that diamond can be synthesized from a mixture of CH4 an d N2 without adding any H-2. This new synthesis is sharply different f rom the common practice of diamond growth by chemical vapor deposition , which uses a hydrogen-rich mixture of CH4 and H-2. In this new appro ach, nitrogen becomes an active component of microwave plasma leading to diamond growth. Nitrogen participates in abstraction of hydrogen fr om the diamond surface. We hypothesize that formation of HCN is an ind ication of hydrogen abstraction that allows diamond to grow from CH4+N 2 mixtures. As a consequence of surface processes, the crystal structu re of the grown diamond is distorted. The sequence of tetrahedral laye rs is mixed (cubic and hexagonal) and it suffers from turbostatic diso rder. Diamond films were characterized by x-ray diffraction, Auger ele ctron spectroscopy, x-ray photoelectron spectroscopy, and Raman spectr oscopy.