Publication Details

Category Text Publication
Reference Category Journals
DOI 10.1063/1.362936
Title (Primary) The influence of chemisorption on the defect equilibrium of metal oxide thin films
Author Geistlinger, H.
Source Titel Journal of Applied Physics
Year 1996
Department BOFO; BOSYS
Volume 80
Issue 3
Page From 1370
Page To 1380
Language englisch

Using the exact charge density of intrinsic point defects of metal oxides (MOs), the phenomenological electron theory of chemisorption, developed by Volkenstein, is applied to acceptorlike and donorlike chemisorption on MO thin films for the whole ξ region (where ξ=D/LD, D is the film thickness, and LD is Debye length). The experimental temperature and oxygen partial pressure dependence of the averaged electron concentration 〈n〉(pO2,T)∝eEA/kTpO2m(T) for polycrystalline ZnO films are discussed on the bases of three different models: the Schottky‐defect model, the Volkenstein model for electronic equilibrium, and the comprehensive model for complete equilibrium. It turns out that a Schottky‐defect model that uses single‐crystal‐mass action constants will not yield the experimental high temperature limit (T=1000 K: EA=1.6 eV, m=0.26). This limit is obtained using a higher averaged concentration of oxygen vacancies for polycrystalline films (due to the presence of grain boundaries). The comparison between the electronic and complete equilibrium shows that the screening of the surface charge through mobile positively charged oxygen vacancies has a tremendous reducing effect of about 30% of the surface potential in the temperature range considered.

Persistent UFZ Identifier
Geistlinger, H. (1996):
The influence of chemisorption on the defect equilibrium of metal oxide thin films
J. Appl. Phys. 80 (3), 1370 - 1380 10.1063/1.362936