A Novelly Designed Ba0.6Sr0.4TiO3 Film with High Tunability and Low Dielectric Loss

作者：Liao, Jiaxuan^*; Huang, Jiaqi; Wei, Xubo; Xu, Ziqiang; Wang, Peng

来源：Integrated Ferroelectrics, 2014, 152(1): 90-96.

DOI：10.1080/10584587.2014.901868

• Mn and Y alternate doping
• preheating
• BST films
• combination of dielectric properties

Manganese (Mn) and yttrium (Y) alternately doped Ba0.6Sr0.4TiO3 (BST) films are novelly designed as MnBST/YBST/MnBST/YBST and prepared layer-after-layer on Pt wafer electrodes, and two films where one with the first layer preheated (1Mn/YBST) and the other with four layers preheated (4Mn/YBST) are focused on. XRD shows that two films grow along (110) orientation and reveal ABO(3) cubic perovskite structures and donor doping, but 4Mn/YBST film shows larger average grain size. SEM demonstrates that 1Mn/YBST film is composed of one 630nm-thick layer with nodular microstructure and the other 570nm-thick surface layer with columnar microstructure, whereas 4Mn/YBST film is 670nm thick with nodular microstructure. AFM shows that two films are smooth with no cracks, but 4Mn/YBST film is denser with smaller roughness. Two films show more than 55% high tunabilities, but 4Mn/YBST film also reveals low losses of 0.0062 similar to 0.0156 and high figure of merit (FOM) of near 90 at -35V and 100kHz, fully meeting the needs of tunable microwave applications.

• 出版日期2014-3-24