Publisher : The Korean Institute of Surface Engineering
DOI : 10.5695/JKISE.2011.44.4.131
Title & Authors
A Kinetic Study on the Growth of Nanocrystalline Diamond Particles to Thin Film on Silicon Substrate Jung, Doo-Young; Kang, Chan-Hyoung;
A kinetic study has been made for the growth of nanocrystalline diamond (NCD) particles to a continuous thin film on silicon substrate in a microwave plasma chemical vapor deposition reactor. Parameters of deposition have been microwave power of 1.2 kW, the chamber pressure of 110 Torr, and the Ar/ ratio of 200/2 sccm. The deposition has been carried out at temperatures in the range of for the times of 0.5~16 h. It has been revealed that a continuous diamond film evolves from the growth and coalescence of diamond crystallites (or particles), which have been heterogeneously nucleated at the previously scratched sites. The diamond particles grow following an = k't relationship, where h is the height of particles, k' is the particle growth rate constant, and t is the deposition time. The k' values at the different deposition temperatures satisfy an Arrhenius equation with the apparent activation energy of 4.37 kcal/mol or 0.19 eV/ atom. The rate limiting step should be the diffusion of carbon species over the Si substrate surface. The growth of diamond film thickness (H) shows an H = kt relationship with deposition time, t. The film growth rate constant, k, values at the different deposition temperatures show another Arrhenius-type expression with the apparent activation energy of 3.89 kcal/mol or 0.17 eV/atom. In this case, the rate limiting step might be the incorporation reaction of carbon species from the plasma on the film surface.
Nanocrystalline diamond film;Microwave plasma CVD;Nucleation and growth;Arrhenius equation;Activation energy;