Origin of surface conductivity in diamond

Beitrag in einer Fachzeitschrift


Details zur Publikation

Autor(en): Ristein J, Maier F, Ley L
Zeitschrift: Physical Review Letters
Verlag: American Physical Society
Jahr der Veröffentlichung: 2000
Band: 85
Heftnummer: 16
Seitenbereich: 3472-5
ISSN: 0031-9007


Abstract

Experimental evidence is presented which supports an electrochemical model for the pronounced surface conductivity of hydrogen-terminated diamond. In this model hydrogenation rises the valence band maximum (VBM) of diamond sufficiently with respect to the vacuum level to place it just above the chemical potential of electrons in the liquid phase (μe) of a mildly acidic water layer physisorbed at the surface. Electron transfer from diamond to the H3O+/(H2O + H2) redox couple accounts for the hole accumulation layer. In equilibrium, the diamond surface Fermi level position is pinned at μe which coincides essentially with the VBM. Small variations in that Fermi level position with respect to VBM and thus variations in conductivity with the pH value of the wetting layer and the H2 partial pressure are quantitatively accounted for via Nernst's equation.


FAU-Autoren / FAU-Herausgeber

Ley, Lothar Prof. Dr.
Naturwissenschaftliche Fakultät
Maier, Florian Dr.
Lehrstuhl für Physikalische Chemie II
Ristein, Jürgen apl. Prof. Dr.
Lehrstuhl für Laserphysik

Zuletzt aktualisiert 2018-09-08 um 05:53