The discussion revolves around the value of one monolayer (ML) in nanometers, particularly in the context of material deposition and its dependence on specific materials and crystal structures. Participants explore the variability of this value and its implications for experimental setups.
Participants generally agree that the value of 1 ML is not fixed and depends on various factors, but there is no consensus on a specific value or how to interpret it in all contexts. Multiple competing views remain regarding the implications of monolayer thickness in specific examples.
Limitations include the dependence on specific material properties and crystal structures, as well as the lack of universal definitions for monolayer thickness across different contexts.
yzou_ua said:Always be used in experiments... but when it appears in literature, most authors never tell the exact value of 1 ML (monolayer).
So, what is the value, generally??
ZapperZ said:This is not a universal value. It depends on the material and crystal structure of what is being deposited.
Zz.
yzou_ua said:So w/o telling from author, we can never know it??
ZapperZ said:Unless you know the crystal structure. If the author usually doesn't say, then it's a "common" material that he/she would assume that everyone knows already. This is often the case for, say, high-Tc superconductors or well-known compounds such as Al2O3 or TiN.
Zz.
f95toli said:2 monolayers will probably be of that order of magnitude, yes. But the exact value will depend on e.g. the termination of the surface etc.
Also, 2.5ML would mean 2 complette layers and one half-filled layer; meaning the top-most layer does not cover the whole surface. Again, what it looks really like will depend on the materials etc.
Btw, the reason the thickness is given in monolayers is because it is much easier to "count" the number of layers (using RHEED oscillations) during the film growth than it is to actually measure the thickness of the film.