Unusual conductivity in Ga2O3 thin film

Author: Tinatin Tsiskaridze
Co-authors: Bachana Beradze, Ekaterine Chikoidze
Keywords: charge concentartion, increase of electrons mobilityd, surface electric field, triangular well
Annotation:

In the presented work we tried to explain high n-conductivity in Ga2O3 thin films – the effect of surface electric field, despite the wide band gap (4.9 eV) of the material. Thermodynamic analysis which helps us to calculate the concentration of charge carriers as a synthesis parameters function, shows that it is impossible to get such high conductivity in a mentioned compound. The experimental result can be explained by existence of a surface electric field. Its creation is related to surface defects. Surface electric field causes electrons’ localization in surface adjacent film and electric levels discretization. On the one hand it causes effective growth of electrons concentration in near surface region, and on the other hand – increase of electrons mobility. This must have caused the experimental result- unusually high conductivity of that films. We have solved the following problem: it is reviewed infinite triangle potential well, which is created by electric field. There are electron in this well. It is found the eigen functions and eigen values for electrons and holes. The calculations are made for real electric field which was measured on an experiment. It is shown that such fields really can cause quite big lectron localization and creation of quazi-2D elecgtron gas.