1 research outputs found
Effect of Doping Density on the Charge Rearrangement and Interface Dipole at the MoleculeāSilicon Interface
The
interface level alignment of alkyl and alkenyl monolayers,
covalently bound to oxide-free Si substrates of various doping levels,
is studied using X-ray photoelectron spectroscopy. Using shifts in
the C 1s and Si 2p photoelectron peaks as a sensitive probe, we find
that charge distribution around the covalent SiāC bond dipole
changes according to the initial position of the Fermi level within
the Si substrate. This shows that the interface dipole is not fixed
but rather changes with the doping level. These results set limits
to the applicability of simple models to describe level alignment
at interfaces and show that the interface bond and dipole may change
according to the electrostatic potential at the interface