Like metals, is Ea/Ec (ratio of absorption energy to bulk cohesive energy) also a good figure of merit to determine the growth morphology of compound material / compound semiconductor on graphene? For instance, I would like to grow binary semiconductor (InP) on graphene. In that case, can I predict the growth morphology of such binary material on graphene based on such ratio?
Metals on graphene: interactions, growth morphology and thermal stability, Crystals 2013, 3.
Article Growth morphology and thermal stability of metal islands on graphene
I think that increase Ea/Ec stabilize flat film. So if such metals as Fe forms islands, in spite of the fact that, Fe forms carbides, materials which did not forms carbides will forms islands at any case.
Thanks, Dr. Titov, for your valuable comments. If I understood correctly from your comments, that is if individual atoms In and P on graphene have a low Ea/Ec, i.e. form islands, then binary materials consisting of these atoms on graphene will also have a low Ea/Ec leading to a 3D growth morphology.
Hi Shamsul.
That is an interesting question, but I did not understand exactly what the "absorption energy" is. First, trying to clarify this point, I would like to mention that generally the energies related to the growth are based on the homologous temperature (Tgrowth/Tmelt, both in Kelvin). This is generally used to analyze the structure development of films. In the case of energy enhanced depositions, when energetic particles come from a plasma or ion sources for exemple there are contributions of this extra energy to the growth [see for instance J.A. Thornton and D.W. Hoffman, Thin Solid Films, 171 (1989) 5-31 "STRESS-RELATED EFFECTS IN THIN FILMS"].
In general terms, in the nucleation stage and when the surface diffusion length of the species is high enough (a good fraction of the size of the formed clusters), important aspects concerning the 2D and 3D growth regimes are the surface energies (or surface tension) of both the substrate, substrate-film, and film-vapor interfaces. If the interface energy is higher than the film-vapor + substrate, the tendency is to form 3D droplets (in the Volmer-Weber growth), and when the (film-vapor + film-substrate) < substrate surface energies (Frank - van der Merwe growth). This scheme has been sucessful in several situations when using a bulk substrate. It would be very interesting to analyze how this traditional scheme could be modified in your situation where the droplet of film are deposited on graphene, so your question was a very good. I hope to have contributed a little to the discussion, and I will keep following the other contributions.
Best regards, and great New Year!
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