Numerical analysis of an influence of oxygen adsorption at a SnO2 surface on the electronic parameters of the induced depletion layer

• Published in: Physica Status Solidi (b) 2011-03, Vol.248 (3), p.694-699
• Main Author: Izydorczyk, Weronika
• Format: Article
• Language: English
• Subjects: Adsorption; Condensed matter: electronic structure, electrical, magnetic, and optical properties; Depletion; depletion layers; Electric potential; Electronic structure and electrical properties of surfaces, interfaces, thin films and low-dimensional structures; Exact sciences and technology; Impurity and defect levels; energy states of adsorbed species; Mathematical analysis; modelling; Physics; SnO2; Surface and interface electron states; Surface chemistry; surfaces; Tin dioxide; Tin oxides; Vacancies
• ISSN: 0370-1972; 1521-3951; 1521-3951
• DOI: 10.1002/pssb.201046385

In this work the influence of oxidation of a SnO2 thin film on the development of a depletion layer was studied by using computer simulations. The surface potential and in‐depth potential profiles in the depletion region were calculated by solving the Poisson–Boltzmann equation for finite SnO2 flat grains (partially or totally depleted) using slab geometry. The effect of the donor (oxygen vacancies in the bulk) mobility on electrical potential inside grains with different thicknesses was discussed. Furthermore, in‐depth profiles of mobile donor Nd(r) and electron n(r) concentrations in the depletion layer were computed for different densities of negative charge trapped in the surface states, as a result of oxygen adsorption. It was assumed that the bulk oxygen vacancies (donors) are singly ionized and mobile.