原子氧处理减小多晶PZT-PMN薄膜漏电流的实验研究

漏电流是铁电薄膜应用过程中的关键问题。本文通过磁控溅射法制备了结晶性能良好的铌镁锆钛酸铅(PZT-PMN)铁电薄膜,并在室温下用原子氧对其进行处理,研究了原子氧对PZT-PMN薄膜表层微观结构和漏电流的影响。实验结果表明:经原子氧处理后的PZT-PMN薄膜,①表面粗糙度下降且有非晶层形成;②表层有大量的氧原子进入;③漏电流密度减小了大约一个数量级,外加电压为2.5 V时,未处理样品的漏电流密度为3×10-5A/cm2,处理样品的漏电流密度降为4.5×10-6A/cm2。原子氧对PZT-PMN薄膜内部晶界、缺陷的钝化是薄膜漏电流减小的原因。

Leakage Current Reduction of Polycrystalline PZT-PMN Films Modified with Oxygen Plasma

Here,we addressed the reduction of the leakage current of the piezoelectric(PZT) ceramics and lead-magnesium-niobate(PMN)ceramic films,deposited by magnetron sputtering,and modified by oxygen plasma immersion at room temperature.Its microstructures and properties,before and after surface modification with oxygen plasma,were characterized with X-ray diffraction,X-ray photoelectron spectroscopy and scanning electron microscopy and conventional probes.The results show that the surface modification with oxygen plasma significantly reduced the leakage current by about one order of magnitude,and smoothed the surface.Possible mechanisms responsible for the reductions of the leakage current and surface roughness were also tentatively discussed.