硅基PZT薄膜的制备与工艺损伤

Fabrication of silicon-based PZT films and process-induced damage problems

以 Pb Ti O3(PT)作为种子层 ,在 Si衬底上用改进的溶胶凝胶法制备了 PZT薄膜 ,并用 RIE法刻蚀形成 MFM(金属铁电层金属 )结构的电容 ,以用于铁电随机存取存储器 (Fe RAM)中。测得 PZT薄膜相对介电常数、矫顽场和剩余极化强度分别为 10 0 0 ,30 k V/ cm和 16 μC/ cm2 ,漏电流在 0 .1n A / cm2 量级 ,达到 Fe RAM的应用要求。铁电膜与CMOS电路集成时对铁电膜的铁电性可能造成的工艺损伤(如刻蚀损伤、氢损伤和应力损伤等 )的物理机制进行了初步研究和讨论 。

Lead zirconate titanate (PZT) ferroelectric film using lead titanate (PT) as the seeding layers was prepared on a silicon wafer using the sol gel method. The film was then etched using reactive ion etching to form an MFM (metal ferroelectric metal) structure capacitor for FeRAM applications. The ferroelectric capacitor has a high dielectric constant of about 1 000, an ultra low leakage current density of 0.1 nA/cm 2, a remnant polarization of 16 μC/cm 2, and a coercive field of about 30 kV/cm, and is almost fatigue free. Some process induced damage, such as etching induced damage, hydrogen induced degradation, and stresses, which cause degradation of the PZT film have been investigated.