Effect of co-adsorbed dopants on initial diamond growth steps: H abstraction from an adsorbed CH3
2009 (English)In: Diamond and related materials, ISSN 0925-9635, Vol. 18, no 9, 1152-1156 p.Article in journal (Refereed) Published
The effect induced by a neighbouring co-adsorbed dopant on H abstraction from an adsorbed CH3 species on diamond has been investigated by using an ultra-soft pseudo-potential density functional theory (DFT) method under periodic boundary conditions. Both the (100) and (111) diamond surface orientations were considered with various types of dopants in two different hydrogenated forms; AHx (A = N, B, S, or P; X = 0 or 1 for S; X = 1 or 2 for N, B and P, and X = 2 or 3 for C). The H abstraction by gaseous radical H was found to be energetically favoured by the presence of the dopants in all of their different hydrogenated forms. For NH2, SH, or PH2, this effect is induced by a destabilisation of the diamond surface by sterical repulsions between the adsorbed growth species CH3 and the co-adsorbed dopant. For BH2 and the dopants in their radical form, the abstraction reaction is favoured due to the formation of a new covalent bond between the dopant and the co-adsorbed CH2 (product of the abstraction reaction), which strongly stabilises the surface after the abstraction process.
Place, publisher, year, edition, pages
2009. Vol. 18, no 9, 1152-1156 p.
Quantum mechanics, Diamond growth, Dopant effects
IdentifiersURN: urn:nbn:se:uu:diva-98004DOI: 10.1016/j.diamond.2009.02.033ISI: 000268610700018OAI: oai:DiVA.org:uu-98004DiVA: diva2:173157