摘要
Ba_(x)Sr_(1–x)TiO_(3)(BST)铁电薄膜因为拥有高介电常数、强电场调谐性和较低的微波频段介电损耗可应用于微波可调谐器件.然而铁电材料中普遍存在的介电常数-温度依赖性使得常规单组分铁电薄膜的高可调率温区受制于相变温度,难以满足宽温域适用性的需求.为研究可用于宽温域功能器件的铁电薄膜,采用脉冲激光沉积(PLD)技术制备了单组分Ba_(0.5)Sr_(0.5)TiO_(3)薄膜、Ba_(0.2)Sr_(0.8)TiO_(3)薄膜以及Ba_(0.2)Sr_(0.8)TiO_(3)/Ba_(0.5)Sr_(0.5)TiO_(3)异质结构薄膜.通过对比其介电性能,发现垂直方向上Ba/Sr组分分布可有效改善BST薄膜的温度依赖性,然而异质结构的构建可能带来界面问题,同时也使其品质因子难以提升.本文提出采用独特的水平方向连续组分薄膜制备技术制备BST组合薄膜,有望在拓宽BST薄膜相变温区的同时避免界面控制的难题.
Ba_(x)Sr_(_(1–x))TiO_(3)(BST)ferroelectric thin films are widely used in microwave tunable devices due to their high dielectric constants,strong electric field tunabilities and low microwave losses.However,because of the temperature dependence of dielectric constant in ferroelectric material,the high-tunability for conventional single component ferroelectric thin film can only be achieved in the vicinity of Curie Temperature(TC)which leads the ferroelectric thin films to be difficult to operate in a wide temperature range.To obtain ferroelectric thin films for temperature stable functional devices,single composition Ba_(0.2)Sr_(0.8)TiO_(3) thin films,Ba_(0.5)Sr_(0.5)TiO_(3) thin films,and Ba_(0.2)Sr_(0.8)TiO_(3)/Ba_(0.5)Sr_(0.5)TiO_(3) heterostructure thin films are deposited by pulsed laser deposition(PLD).By comparing their dielectric properties in a wide temperature range,it is found that the temperature sensitivity of BST film can be effectively reduced by introducing a composition gradient along the epita_(x)ial direction.However,the heterostructure engineering may bring extra troubles caused by interfaces,which may limit the quality factor Q.In this paper,we extend our combinatorial film deposition technique to ferroelectric materials,and we successfully fabricate in-plane composition-spread Ba_(1–x)SrxTiO_(3) thin films,which are expected to broaden the phase transition temperature ranges of BST films while avoiding the problem of interface control.
作者
熊沛雨
倪壮
林泽丰
柏欣博
刘天想
张翔宇
袁洁
王旭
石兢
金魁
Xiong Pei-Yu;Ni Zhuang;Lin Ze-Feng;Bai Xin-Bo;Liu Tian-Xiang;Zhang Xiang-Yu;Yuan Jie;Wang Xu;Shi Jing;Jin Kui(School of Physics and Technology,Wuhan University,Wuhan 430072,China;Beijing National Laboratory for Condensed Matter Physics,Institute of Physics,Chinese Academy of Sciences,Beijing 100190,China)
出处
《物理学报》
SCIE
EI
CAS
CSCD
北大核心
2023年第9期178-186,共9页
Acta Physica Sinica
基金
国家重点研发计划(批准号:2021YFA0718700)资助的课题。
作者简介
通信作者:王旭.E-mail:risingsunwx@iphy.ac.cn;通信作者:王旭.E-mail:jshi@whu.edu.cn。
