Influence of platinum interlayers on the electrical properties of RuO2/Pb(Zr0.53Ti0.47)O3/RuO2 capacitor heterostructures

Abstract

Lead zirconate titanate, Pb(ZrxTi1−x)O3 or PZT, thin films grown on RuO2 electrodes by the sol-gel process have excellent resistance to polarization fatigue, but they generally have two drawbacks. The films have high leakage currents and large property variation. In this letter we show that the use of a thin Pt layer (100 Å) deposited on the bottom RuO2 electrode to fabricate RuO2/PZT/Pt/RuO2/(100)MgO capacitors has two important effects. It reduces capacitor leakage by two to four orders of magnitude and it significantly reduces the large property variation. In addition, these capacitors retain their excellent resistance to polarization fatigue which is characteristic of the RuO2/PZT/RuO2 heterostructure.

Atomic structure of (111) SrTiO3∕Pt interfaces

“…Metal/ferroelectric interfaces control properties such as leakage currents [4], ferroelectric fatigue [5], tunnel barriers [3], and "interfacial deadlayers", i.e. an apparent thickness dependence of the polarizability of paraelectric perovskite thin films [6].…”

Spatial variation of ferroelectric properties in Pb(Zr0.3, Ti0.7)O3 thin films studied by atomic force microscopy

“…Also, having a top electrode is relevant since the electrode material is a critical component of the fatigue process. 11,12 Piezoelectric measurements were performed in contact mode using a commercially available AFM ͑PSI M5͒ that employed conducting diamond tips. The experimental setup is an improved version of a previously described apparatus.…”

Effect of Phase Transition Temperature of Bati0.9Sn0.1o3 on the Operating Mode of Ferroelectricrandom Access Memories (FeRAM)

“…Therefore, we can replace the (SBT) and (BIT) by another ferroelectric material, as BaTiO 3 (BTS), which have a low process temperature, a large remanent polarization and higher dielectric permittivity. Furthermore BaTiO 3 has the highest dielectric constant ≈10 4 at the phase transition temperature (Curie temperature, Tc=120°C), while at room temperature the dielectric constant decreases to 1/5.10 4 , which greatly limits its applications, and causes a big problem because in practice it is not possible to program the memory tricks to 120°C. It is supposed that theoretically the Curie point of BaTiO 3 [11].…”

“…Among them, PbZr x Ti 1-x O 3 (PZT) thin films have been extensively investigated, since PZT exhibits several advantages, such as a relatively low processing temperature. However, PZT exhibits a serious disadvantage in switching endurance with common Pt electrodes [3][4]. Although fatigue resistance of PZT has been improved with oxide electrodes, usage of oxide electrode increases complexity of fabrication process and cost [4,21,22].…”

“…However, PZT exhibits a serious disadvantage in switching endurance with common Pt electrodes [3][4]. Although fatigue resistance of PZT has been improved with oxide electrodes, usage of oxide electrode increases complexity of fabrication process and cost [4,21,22]. Furthermore, PZT contains an environmentally hazardous element, Pb.…”