标题：THE DIELECTRIC AND PIEZOELECTRIC PROPERTIES OF YCA(4)O(BO3)(3) CRYSTAL ANNEALED IN CRITICAL CONDITION
作者：Tian, Shi-wei; Li, Li-li; Yu, Fa-peng; Li, Yan-lu; Cheng, Xiu-feng; Wang, Zheng-ping; Zhao, Xian
作者机构：[Tian, Shi-wei; Li, Li-li; Yu, Fa-peng; Li, Yan-lu; Cheng, Xiu-feng; Wang, Zheng-ping; Zhao, Xian] Shandong Univ, Inst Crystal Mat, Adv Res Ctr Opt, J 更多
会议名称：13th Symposium on Piezoelectrcity, Acoustic Waves, and Device Applications (SPAWDA)
会议日期：JAN 11-14, 2019
来源：PROCEEDINGS OF THE 2019 13TH SYMPOSIUM ON PIEZOELECTRICITY, ACOUSTIC WAVES AND DEVICE APPLICATIONS (SPAWDA)
关键词：YCOB; High temperature; Piezoelectric; Critical condition; XPS
摘要：The YCa4O(BO3)(3) (YCOB) crystal is an attractive piezoelectric material for sensing at elevated temperatures. In this paper, the dielectric and piezoelectric properties of YCOB crystal annealed at high temperature of 1100 degrees C and low atmosphere pressure of 2 Pa for 24 h were reported. Comparing to the pristine YCOB crystal, the relative dielectric permittivity (epsilon(22)/epsilon(0)) slightly increased after annealing, while the piezoelectric coefficient (d(26)) got decreased, with a variation of <7%. The chemical bonding for the annealed YCOB was studied using X-ray photoelectron spectroscopy, from which the variations of binding energies of B, Ca, and Y decreased below 0.2 eV, indicating the stable electronic structure of YCOB crystal. The vacancy formation energies for Y, Ca, O, and B atoms in YCOB crystal were also analyzed via first principle calculations. The O atom was found to possess the lowest vacancy formation energy, thus easier to evaporate during critical annealing and easier to compensate than other atoms. The vacancy defects are believed to be the main factor dominant the variations of dielectric and piezoelectric properties.