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In this thesis, the binary co-doped Sol-gel prepared barium strontium titanate (Ba0.6Sr0.4TiO3, BST) thin-film dielectric properties . Commenced focusing on improving the dielectric properties of BST thin , combined with the current research trends in optimizing the dielectric properties of BST , on a dollar - doped binary codoped study , and BST alternately doped attempt . XRD, AFM, XPS and other modern materials analysis methods to characterize the film microstructure , surface morphology and composition , and to explore the link between the composition, process , structure and performance . First, the study of doping the BST phase changes in the structure before and after , with the test results , calmly difference factor angle to determine the influence of doping elements on the BST phase structure . BST film surface morphology and surface composition analysis by AFM and XPS . The analysis shows that : the the doped BST crystal grain size after the change and the elements of the doped , a doped perovskite structure of BST content changed . Selected cerium , manganese BST A bits doping , the B bit doped with AB bit codoped comparative study . The results show that : doped BST film dielectric properties have been optimized , the more advantages which cerium manganese binary co-doped dielectric properties and dielectric loss can be reduced to a minimum 0.014,20 V bias merit factor 16.9 ; cerium co-doped overcome manganese cerium doped Withstand poor . Second, to further reduce the dielectric loss of BST thin alternating doping research attempts . Study the impact of the doping concentration and thin film doped dielectric properties of BST thin layers of alternating . Alternately doping while maintaining on the basis of a certain merit factor significantly reduces the dielectric loss , the film also has a good withstand voltage characteristic , a steady loss - bias characteristics . Additionally, the test frequency is increased from 100KHz to 1MHz , BST thin film dielectric properties show a good frequency stability performance .
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