MgxZn1-xO thin films were prepared on quartz substrates by a sol-gel dip-coating process. Structural and optical properties were investigated using X-ray diffraction, optical absorbance, and photoluminescence (PL). Results showed that the MgxZn1-xO thin films retained the ZnO hexagonal crystal structure with very little lattice deformation compared to the pure ZnO films. The optical band-gap of the MgxZn1-xO thin films varied from 3.28 to 3.73 eV as the Mg content x was increased from 0.0 to 0.3, and it can be formulated using the equation E-g = 3.28 + 1.53x. Results also showed good PL characteristics of these films with strong band-edge UV emission. Like the absorption, the emission energy also shifted towards higher photon energy as the Mg content x in the film was increased. (C) 2004 Elsevier B.V. All rights reserved.