采用静电自组装方法在五氧化二钽(Ta₂O₅)介质氧化膜上制备了聚二烯丙基二甲基氯化铵(PDDA)/聚苯乙烯磺酸钠(PSS)和聚二烯丙基二甲基氯化铵/聚-3,4-乙烯二氧噻吩-聚苯乙烯磺酸钠(PEDOT-PSS)超薄膜. 研究了两种自组装超薄膜在Ta₂O₅ 介质氧化薄膜上的组装特性. 结果表明两种自组装膜能够稳定地组装于Ta₂O₅ 介质膜表面, 并有效降低薄膜的表面粗糙度. 进一步研究了两种自组装超薄膜修饰的Ta₂O₅ 电容结构的电性能. 结果表明静电自组装膜对Ta₂O₅ 介质膜表面进行修饰后, 有效地隔离了介质氧化膜中的缺陷, 降低了电容的漏电流并提高耐电压能力; 研究还发现不同厚度的超薄膜对Ta₂O₅ 电容结构的耐压特性有不同程度的影响, 较厚的薄膜可以更好地提高电容的耐压能力并降低漏电流, 但会增加电容的等效串联电阻(ESR). 另外, 在相同薄膜层数的情况下, 聚合物电解质PEDOT-PSS 良好的导电性能降低了复合超薄膜的电阻, 使得PDDA/PEDOT-PSS 修饰的电容结构ESR 值较低.

Ultrathin films of poly-diallyldimethylammonium chloride (PDDA)/polystyrene sulfonate (PSS) and PDDA/poly(3,4-ethylene dioxythiophene)-polystyrene sulfonate (PEDOT-PSS) were constructed on Ta₂O₅ films through layer-by-layer electrostatic self-assembly (ESA) method for a surface modification purpose. The self-assembly ability of PDDA/PSS and PDDA/PEDOT-PSS ultrathin films on Ta₂O₅ film was investigated. The results showed that the ESA ultrathin films can be constructed on Ta₂O₅ film surface with a layer-by-layer deposition method, and the Ta₂O₅ film covered with ESA film exhibited smoother surface roughness compared with Ta₂O₅ film without surface modification. Moreover, the electronic performance of Ta/Ta₂O₅/ESA films/polymer film capacitor structure was investigated. The results revealed that the capacitor composed of ultrathin ESA film exhibited better anti-voltage endurance ability and less leakage current, which resulted from the isolation of leakage current channel in Ta₂O₅ films because of surface coverage of ultrathin ESA film on Ta₂O₅. It also can be found that the thicker ultrathin ESA film for surface modification resulted in better anti-voltage endurance ability and higher equivalent series resistance (ESR) of Ta₂O₅ capacitor. The further investigation confirmed that lower ESR of capacitor composed of PDDA/PEDOT-PSS ESA films because of high conductive ability of PEDOT-PSS.