锰掺杂和氧化铌种子层对铌酸钾钠薄膜电性能的影响

Effect of Mn Doping and Niobium Oxide Seed Layer on Electrical Properties of Potassium Sodium Niobate Thin Films

采用溶胶凝胶法制备铌酸钾钠(KNN)系薄膜,根据薄膜的微观形貌结构、电学性能和漏电机制研究了Mn掺杂和种子层对KNN薄膜性能的影响。结果表明:锰掺杂能显著提高薄膜的铁电性能和降低漏电流;在薄膜与衬底之间加入氧化铌种子层,使薄膜的电学性能进一步提高。薄膜的漏电流机制由空间电荷传导和欧姆传导转为欧姆传导和肖特基发射,使漏电流和剩余极化值减小。在强度为600 kV/cm的电场中,有种子层且掺10%(摩尔分数)Mn的KNN薄膜,其最大极化值和剩余极化值分别为20.33μC/cm^(2)和2.94μC/cm^(2)。

High-quality films of lead-free piezoelectric x Mn-doped KNaNbO_(3)(x=0,0.05,0.10)were successfully deposited onto Pt(111)/Ti/SiO_(2)/Si(100)substrates by sol-gel method.The effect of Mn doping and seed layer of niobium oxide on the microstructure,dielectric properties,ferroelectric properties,and leakage current of the KNN films was investigated in detail.The results show that Mn doping can significantly improve the ferroelectric properties and reduce the leakage current of the prepared films.After inserted a seed layer of niobium oxide in between the films and the substrate,the leakage current related mechanism of KNN films changes from space charge conduction and ohmic conduction to ohmic conduction and Schottky emission,correspondingly,the leakage current is further reduced.It is found that when the electric field is 600 kV/cm,the maximum polarization value of the 10%mol Mn doped KNN films with a inserted seed layer is 20.33μC/cm^(2),and the residual polarization value is 2.94μC/cm^(2).