Lattice stress gradients in thin films deposited by reactive sputtering

Among physical methods for thin films preparation, diode sputtering plays a very important role because almost all materials can be prepared by this technique. Reactive sputtering as a modification of this method is commonly used when preparing oxide and nitride thin films. Using r.f. reactive sputtering methods to obtain ZnO films, compressive stresses arise when a growing film is bombarded by energetic atoms or ions. A simple method to determine the lattice stress gradients in ZnO films by using the X-ray diffraction analysis of asymmetric line profiles is presented. The lattice stress gradient in ZnO films depends on the substrate temperature applied during the deposition and on the other conditions as substrate material used or on the ordering of layers in multilayered structures.