Mn-substituted BiFeO3 (BFO) thin films were fabricated by chemical solution deposition on Pt∕Ti∕SiO2∕Si(100) structures. X-ray diffraction analysis revealed that the BFO lattice was somewhat distorted when 5% of Fe atoms were substituted with Mn atoms, but no secondary phase appeared by Mn substitution up to 20%. The leakage current density at higher electric field than 0.6MV∕cm decreased by Mn substitution of 3%–5%, compared with a pure BFO film. Because of the low leakage current density in the high electric field region, well saturated polarization hysteresis loops with remanent polarization of 100μC∕cm2 were observed in the 5% Mn-substituted BFO films at a measurement frequency of 1kHz.
Articles you may be interested inHigh-temperature ferroelectric behaviors of poly(vinylidene fluoride-trifluoroethylene) copolymer ultrathin films with electroactive interlayers J. Appl. Phys. 111, 064506 (2012); 10.1063/1.3699051 Polarization behavior of poly(vinylidene fluoride-trifluoroethylene) copolymer ferroelectric thin film capacitors for nonvolatile memory application in flexible electronics J. Appl. Phys. 108, 094102 (2010); 10.1063/1.3500428 Interacting and noninteracting dipole systems in ferroelectric poly(vinylidene fluoride-trifluoroethylene) copolymer J. Appl. Phys. 108, 084109 (2010); 10.1063/1.3499614 Domain stabilization effect of interlayer on ferroelectric poly(vinylidene fluoride-trifluoroethylene) copolymer ultrathin film Electrical investigations on metal/ferroelectric/insulator/semiconductor structures using poly[vinylidene fluoride trifluoroethylene] as ferroelectric layer for organic nonvolatile memory applications
The current status of ferroelectric random-access memory (FeRAM) technology is reviewed in this article. Presented first is the status of conventional FeRAM, in which the memory cells are composed of ferroelectric capacitors to store the data and cell-selection transistors to access the selected capacitors. Discussed next are recent developments in the field. Pb(Zrx, Ti1–x)O3 (PZT) and SrBi2Ta2O9 (SBT) films are being used to produce 0.13 mμ and 0.18 μm FeRAM cells, respectively, with a stacked capacitor configuration; these cells are easily embedded into logic circuits. A new class of FeRAM called 6T4C—containing static RAM (SRAM) cells composed of six transistors (6T) and four ferroelectric capacitors (4C)—has been commercially produced. This type of FeRAM features a nondestructive readout operation, unlimited read/write cycling, and a fast access time of less than 10 ns. Lastly, the status of field-effect-transistor (FET)-type FeRAM is reviewed, emphasizing that the data retention time of a ferroelectric-gate FET has been improved to more than a month in recent studies.
Ferroelectric random access memory (FeRAM) is a nonvolatile memory, in which data are stored using hysteretic P-E (polarization vs. electric field) characteristics in a ferroelectric film. In this review, history and characteristics of FeRAMs are first introduced. It is described that there are two types of FeRAMs, capacitor-type and FET-type, and that only the capacitor-type FeRAM is now commercially available. In chapter 2, properties of ferroelectric films are discussed from a viewpoint of FeRAM application, in which particular attention is paid to those of Pb(Zr,Ti)O3, SrBi2Ta2O9, and BiFeO3. Then, cell structures and operation principle of the capacitor-type FeRAMs are discussed in chapter 3. It is described that the stacked technology of ferroelectric capacitors and development of new materials with large remanent polarization are important for fabricating high-density memories. Finally, in chapter 4, the optimized gate structure in ferroelectric-gate field-effect transistors is discussed and experimental results showing excellent data retention characteristics are presented.
Mn-substituted (0–10at.%) BiFeO3 (BFO) thin films were fabricated by chemical solution deposition on Pt∕Ti∕SiO2∕Si substrate. X-ray diffraction analysis revealed that no secondary phase appeared even if Fe atoms were substituted with Mn atoms up to 10at.%. However, in the 10at.% Mn-substituted BFO film, the lattice parameters decreased by approximately 0.6%. Substitution of small amount of Mn atoms such as 3–5at.% in BFO films was effective in reducing the leakage current density at a high electric field. The P-E (polarization versus electric field) hysteresis loops were measured by changing frequencies of triangular voltage pulses from 1to100kHz. In Mn-substituted BFO films, frequency dependences of the remanent polarization were not pronounced in the range from 10to100kHz and these measurements showed that the remanent polarization increased with increase of the Mn concentration.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.