Retention characteristics of SrBi2Ta2O9 thin films prepared by metalorganic decomposition

Abstract

Polycrystalline SrBi2Ta2O9 (SBT) ferroelectric thin films were synthesized on Pt/Ti/SiO2/Si substrates by metalorganic decomposition. Electric measurements demonstrate that the polarization decay increases with increasing the write/read voltage within the first second. This could be attributed to the depolarization fields, which increases with increasing the retained polarization. However, we found that the polarization loss is insignificant with different write/read voltages over a range of 1–30 000 S. Furthermore, experiment indicates that there is weak pinning of domain walls existing in SBT, which plays an important role for SBT thin film over a range of 1–30 000 S with a low write/read voltage.

Retention characteristics in Bi3.25La0.75Ti3O12 thin films prepared by the polymeric precursor method

“…This suggests that there no pinning of domain walls in BLT thin film at 5 V write/read voltage. Similar results were observed for SBT thin films deposited on platinum coated silicon substrates where the switchable polarization present no loss with 9 V write/read voltage, while it exhibited polarization loss with 3 V write/read voltage after a waiting period of 30 000 s. 13 Ferroelectricity of the lanthanum doped bismuth titanate thin films was observed with remanent polarization of 21 C/cm 2 and coercive field 44 kV/ cm. The remanent polarization of the BLT film obtained by the soft chemical method is larger than those of other reported in the literature.…”

“…In most retention studies, ferroelectric capacitors exhibited a significant loss in retained polarization within the first 1 s after writing and then a relatively slight decay thereafter. [3][4][5][6][7] Retention loss causes a reduction in the difference between switched ͑P * ͒ and nonswitched ͑Pˆ͒ polarizations, i.e., ⌬P = ͑P * ͒ − ͑Pˆ͒ and leads to an inability to distinguish between the two logic states. Therefore, it is quite important to have good retention properties for any ferroelectric material to be utilized for FRAM applications.…”

“…There have been many reports on the electrical properties of candidate materials, such as SrBi 2 Ta 2 O 9 ͑SBT͒ and Pb͑Zr, Ti͒O 3 …”

Modeling and simulation of low power ferroelectric non-volatile memory tunnel field effect transistors using silicon-doped hafnium oxide as gate dielectric

“…Due to the large number of defects, leakage current, and large lattice mismatch between perovskite ferroelectrics and silicon, it is always necessary to use a buffer layer with a proper interface Table 1 The ferroelectric properties of PZT [29][30][31][32], SBT [33][34][35][36][37][38][39], and Si:HfO 2 [28]. with the substrate.…”

“…The properties of two wellknown perovskite ferroelectrics, Lead Zirconate Titanate (PZT) and Strontium Barium Titanate (SBT), is compared with Si:HfO 2 in Table 1. The recently discovered ferroelectric thin film, Si:HfO 2 [28,6], has a relatively high coercive field that ensures a large memory window [29][30][31][32][33][34][35][36][37][38][39].…”