MgxZn1-xO has been used in various photovoltaic cells because its energy bandgap can be tailored by controlling the Mg composition in this ternary compound. The MgxZn1-xO layers with different surface morphologies including two-dimensional (2-D) films and one-dimensional (1-D) nanostructures are preferred for conventional p-n junction solar cells and polymer-inorganic hybrid solar cells, respectively. The MgxZn1-xO layers are sequentially grown on Ga-doped ZnO (GZO) transparent conductive electrode using metalorganic chemical vapor deposition (MOCVD). The effect of the buffer layers on MgxZn1-xO surface morphology is investigated. It is observed that MgxZn1-xO deposited at 500 C on a low-temperature (similar to 250 degrees C) ZnO buffer layer is in the form of 2-D dense and smooth films, whereas, on a high-temperature (similar to 520 degrees C) ZnO buffer layer is in the form of 1-D nanostructures. Based on the structure characterization results, a growth mechanism in terms of nucleation and texturing is proposed to explain the buffer layer effect. (c) 2011 Elsevier B.V. All rights reserved.