利用新型铁电材料Na0.5Y0.5TiO3(NYTO)薄膜高介电的特点,将其作为MFIS(metal-ferroelectric-insulator-semiconductor,MFIS)电容器的绝缘层,制备出Pt/Pb(Zr0.2Ti0.8)O3/ NYTO/Si结构电容器,并对其进行XRD、SEM、C-V特性测试及I-V特性测试分析.分别对C-V存储窗口(记忆窗口,memory window)与应用电压以及绝缘层膜厚的关系进行了研究,结果表明记忆窗口数值比较理想.绝缘层厚度为40 nm、电容器的应用电压为32 V时,记忆窗口可达13 V.对制备的MFIS电容器I-V特性进行了研究,结果表明器件具备较低的漏电流密度,为1.08×10-6 A/cm2,且其电流传导机制符合空间电荷限制电流导电机制.
Ferroelectric Na0.5Y0.5TiO3(NYTO)film is used as the insulating layer of MFIS(Metal-Ferroelectric-Insulate-Semiconductor)capacitors by its high dielectric properties. The Pt/ Pb(Zr0.2Ti0.8)O3/ NYTO/ Si structure capacitors were prepared, and their XRD, SEM, C-V, and I-V characterristics were tested and analyzed. The dependence of C-V storage window on application voltage and insulation layer thickness were studied separately. The results show that the device has a large memory window when the thickness of the insulation layer is 40 nm. The memory window can reach 13 V with 32 V applied voltage. The MFIS capacitor has low leakage current density of 1.08×10-6 A/cm2. The conduction mechanism of leakage current conforms to space charge limited current conduction mechanism.
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