γ射线辐照对掺Ce钛酸铋铁电薄膜性能的损伤

Damage ofγray irradiation to properties of Ce doped bismuth titanate ferroelectric thin films

采用溶胶-凝胶法在复合基底Pt/Ti/SiO_(2)/Si上制备系列Bi_(3.25)Ce_(0.75)Ti_(3)O_(12)(BCTO)铁电薄膜,并对薄膜进行了不同剂量的γ射线辐照。通过热重-示差扫描量热分析仪(TG-DSC)、X射线衍射仪(XRD)、扫描电子显微镜-能谱仪(SEM-EDS)和铁电测试仪等对辐照前后的薄膜的结构、微观形貌、铁电性、漏电性以及抗疲劳性等进行了对比研究。结果表明:随着对γ射线吸收剂量的增加,薄膜的晶体结构没有改变;薄膜的铁电性能显著减弱,剩余极化2Pr从辐照前的51.5μC/cm^(2)下降到23.7μC/cm^(2);薄膜的漏电流密度增大,从辐照前的0.9×10^(−7)A/cm^(2)增大到7.2×10^(−7)A/cm^(2);在经历10^(12)次开关极化循环后,部分薄膜出现疲劳现象。

A series of ferroelectric thin films of Bi_(3.25)Ce_(0.75)Ti_(3)O_(12)(BCTO)was deposited on a composite substrate of Pt/Ti/SiO_(2)/Si through the sol-gel method,and the deposited films were irradiated with different doses of gamma rays.The crystal structure,surface morphology,ferroelectricity,leakage,and anti-fatigue properties of the deposited films before and after irradiation were compared by thermogravimetric differential scanning calorimetry(TG-DSC),X-ray diffraction(XRD),scanning electron microscope-energy dispersive spectrometer(SEM-EDS)and ferroelectric tester.The results showed that an increase in absorbedγray doses,didn't change the crystal structure of films.The ferroelectricity of the deposited films decreased significantly with the residual polarization 2 Pr decreasing from 51.5μC/cm^(2)to 23.7μC/cm^(2).The leakage current density of the films increased slightly from 0.9×10^(−7)A/cm^(2)to 7.2×10^(−7)A/cm^(2).Some of the films showed fatigue performance after 10^(12) polarization switching cycles.