ZnO, a wide band gap semiconductor (3.37 eV at room temperature) is being explored as an alternative of GaN and promising material for fabricating light emitting diodes (LEDs), laser diodes and solar Simvastatin , , ,  and . Many important properties of ZnO such as large exciton binding energy (60 meV), biocompatibility, non-toxicity and high melting temperature make it a suitable candidate for optical devices . Several recent studies have examined for fabrication and optical properties of doped ZnO films. Group II elements such as Be, Al, Mg and Cd are extensively used in tailoring the band gap of ZnO , ,  and . Cd doping was studied by many authors for narrowing the band gap of ZnO and Mg doping in ZnO is explored for widening the band gap ,  and . Radii of Mg2+ ion (0.57 Å) and Zn2+ ion (0.60 Å) are very close, therefore, Mg can be easily incorporated into the ZnO lattice without any structural deformations . Mg doped ZnO films can be used in bulk acoustic wave devices, ferroelectric RAM, as a window layer in LEDs and solar cells to improve the efficiency and reduce absorption  and . Moreover, according to Schmidt-Grund?s theory, Mg doping in ZnO would increase the excitonic light emitting property of ZnO  and .