The diffusion of these elements into type-IIa natural diamonds was studied. The diffusion was performed in 2 steps. Firstly, the diffusion of Li and O was carried out in a N atmosphere at 860C for 1h. The sample was then placed in a hot-filament chemical vapor deposition growth reactor, and diffusion was carried out for 2h in a H atmosphere (from a B solid source that was placed on the sample surface). After diffusion, the concentration was of the order of 2 x 1016/cm3 at a depth of 0.5μ, and O, N and B were found to range from 1020 to 4 x 1020/cm3 at the same depth.

G.Popovici, R.G.Wilson, T.Sung, M.A.Prelas, S.Khasawinah: Journal of Applied Physics, 1995, 77[10], 5103-6