Conductivity of granular structures based on wide band gap ZnO semiconductors

The experimental studies of granular structures based on ZnO films that are randomly arranged small areas, granules or crystallites, which have different conductivity and are in direct contact, were carried out. The influence of donor complex, consisting of an oxygen vacancy and interstitial zinc atom, the donor impurity Ga, and acceptor impurity Li on the structural conductivity of the films is considered. The specifics of the conductivity in lightly doped wide band gap semiconductors with hydrogen-like impurities are investigated. The influence of grain size and crystallite structure on the conductivity kinetics is discussed. A new method for current density determination as a function of the coordinates for thin conductive films is developed. The experimental data are interpreted on the basis of the percolation theory.