A5023007303- Ferroelectric and Negative Capacitance Devices
- Semiconductor materials and devices
- MXene and MAX Phase Materials
- Advanced Memory and Neural Computing
- Ferroelectric and Piezoelectric Materials
- Advancements in Photolithography Techniques
- Electronic and Structural Properties of Oxides
- Advancements in Semiconductor Devices and Circuit Design
- VLSI and Analog Circuit Testing
- Integrated Circuits and Semiconductor Failure Analysis
- Industrial Vision Systems and Defect Detection
- Copper Interconnects and Reliability
- Semiconductor materials and interfaces
- Acoustic Wave Resonator Technologies
- VLSI and FPGA Design Techniques
- Advanced Surface Polishing Techniques
- Metal and Thin Film Mechanics
- 3D IC and TSV technologies
- Machine Learning in Materials Science
- Organic Light-Emitting Diodes Research
- Electronic Packaging and Soldering Technologies
- Thin-Film Transistor Technologies
- Manufacturing Process and Optimization
- Force Microscopy Techniques and Applications
- Electron and X-Ray Spectroscopy Techniques
NaMLab (Germany)
2016-2025
TU Dresden
2014-2023
GlobalFoundries (United States)
2011-2023
Pusan National University
2021
North Carolina State University
2021
DEVCOM Army Research Laboratory
2021
Novosibirsk State University
2021
Boreskov Institute of Catalysis
2021
Novosibirsk State Technical University
2021
Institute of Semiconductor Physics
2021
The recent progress in ferroelectricity and antiferroelectricity HfO 2 ‐based thin films is reported. Most ferroelectric film research focuses on perovskite structure materials, such as Pb(Zr,Ti)O 3 , BaTiO SrBi Ta O 9 which are considered to be feasible candidate materials for non‐volatile semiconductor memory devices. However, these conventional ferroelectrics suffer from various problems including poor Si‐compatibility, environmental issues related Pb, large physical thickness, low...
Abstract Incipient ferroelectricity is known to occur in perovskites such as SrTiO 3 , KTaO and CaTiO . For the first time it shown that intensively researched HfO 2 thin films (16 nm) also possess ferroelectric properties when aluminium incorporated into host lattice. Polarization measurements on Al:HfO based metal–insulator–metal capacitors show an antiferroelectric‐to‐ferroelectric phase transition depending annealing conditions content. Structural investigation of electrically...
Novel hafnium oxide (HfO 2 )‐based ferroelectrics reveal full scalability and complementary metal semiconductor integratability compared to perovskite‐based that are currently used in nonvolatile ferroelectric random access memories (FeRAMs). Within the lifetime of device, two main regimes wake‐up fatigue can be identified. Up now, mechanisms behind these device stages have not been revealed. Thus, scope this study is an identification root cause for increase remnant polarization during...
Here, we present a structural study on the origin of ferroelectricity in Gd doped HfO2 thin films. We apply aberration corrected high-angle annular dark-field scanning transmission electron microscopy to directly determine underlying lattice type using projected atom positions and measured parameters. Furthermore, nanoscale diffraction methods visualize crystal symmetry elements. Combined, experimental results provide unambiguous evidence for existence non-centrosymmetric orthorhombic phase...
The ferroelectric properties and crystal structure of doped HfO2 thin films were investigated for different thicknesses, electrode materials, annealing conditions. Metal-ferroelectric-metal capacitors containing Gd:HfO2 showed no reduction the polarization within studied thickness range, in contrast to hafnia with other dopants. A qualitative model describing influence basic process parameters on was proposed. structural field cycling behavior examined. This revealed wake-up effect be...
The wake-up behavior of ferroelectric thin film capacitors based on doped hafnium oxide dielectrics in TiN-based metal–insulator–metal structures is reported. After field cycling a remanent polarization up to 40 µC/cm2 and high coercive about 1 MV/cm was observed. Doping HfO2 by different dopants with crystal radius ranging from 54 pm (Si) 132 (Sr) evaluated. In all cases, an improved polarization–voltage hysteresis after visible. For smaller dopant atoms like Si Al stronger pinching the...
Since 2011, ferroelectric HfO 2 has attracted growing interest in both fundamental and application oriented groups. In this material, noteworthy wake‐up fatigue effects alter the shape of polarization hysteresis loop during field cycling. Such changes are problematic for to memories, which require stable hystereses. Herein, electrical structural techniques implemented unveil how cyclic switching nanoscale film structure, modifies hysteresis. Impedance spectroscopy scanning transmission...
Ferroelectric materials are characterized by two stable polarization states that can be switched from one to another applying an electrical field. As of the most promising effects realize nonvolatile memories (NVMs), application ferroelectrics in NVMs has been studied since 1950s. In principle, three different ways read out ferroelectric known: measuring charge-related current flows during switching ferroelectric, polarization-dependent tunneling very thin layers, and threshold voltage shift...
The crystalline phases in hafnia-zirconia solid solution thin films are comprehensively studied by a comparison with the thermodynamic surface or interface/grain boundary energy model.
Recently simulation groups have reported the lanthanide series elements as dopants that strongest effect on stabilization of ferroelectric non-centrosymmetric orthorhombic phase in hafnium oxide. This finding confirms experimental results for lanthanum and gadolinium showing highest remanent polarization values all hafnia-based films until now. However, no comprehensive overview links structural properties to electrical performance detail is available lanthanide-doped hafnia. La:HfO2 appears...
Quantitative phase analysis is first performed on doped Hafnia films to elucidate the structural origin of unexpected ferroelectricity.
The recent discovery of ferroelectricity in thin hafnium oxide films has led to a resurgence interest ferroelectric memory devices. Although both experimental and theoretical studies on this new system have been undertaken, much remains be unveiled regarding its domain landscape switching kinetics. Here we demonstrate that the single domains can directly observed ultrascaled field effect transistors. Using models nucleation explain time, temperature dependence polarization reversal. A simple...
Ferroelectrics are a class of materials that possess variety interactions between electrical, mechanical, and thermal properties have enabled wealth functionalities. To realize integrated systems, the integration these functionalities into semiconductor processes is necessary. this end, complexity well-known ferroelectric materials, e.g., perovskite class, causes severe issues limit its applications in systems. The discovery ferroelectricity hafnium oxide-based brought renewed interest field...
Giant photovoltaic effect due to bulk observed in multiferroic BiFeO3 thin films has triggered a renewed interest on photoferroelectric materials for applications. Tremendous advance been done improve power conversion efficiency (up up 8.1%) photoferroelectrics via absorption increase using narrow bandgap ferroelectrics. Other strategies, as it is the more efficient use of ferroelectric internal electric field, are ongoing. Moreover, by-product, several progress have also achieved...
Ferroelectric field effect transistors (FeFETs) based on ferroelectric hafnium oxide (HfO <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> ) thin films show high potential for future embedded nonvolatile memory applications. However, HfO besides their recently discovered behavior are also prone to undesired charge trapping effects. Therefore, the scope of this paper is verify possibility during standard operation -based FeFET memories....
Hf0.5Zr0.5O2 thin films are one of the most appealing HfO2-based ferroelectric films, which have been researched extensively for their applications in memory devices. In this work, a 1 mol % La-doped film was grown by plasma-assisted atomic layer deposition and annealed at temperatures 450 500 °C to crystallize into desired orthorhombic phase. Despite use lower temperature than that used previous reports, showed highly promising properties-a remnant polarization ∼30 μC/cm2 switching cycle...
To further reduce the power dissipation in nanoscale transistors, fundamental limit posed by Boltzmann distribution of electrons has to be overcome. Stabilization negative capacitance a ferroelectric gate insulator can used achieve this boosting transistor voltage. Up now, is only directly observed polymer and perovskite ferroelectrics, which are incompatible with semiconductor manufacturing. Recently discovered HfO 2 ‐based on other hand, ideally suited for application because their high...
The incorporation of Gd into HfO2 thin films is shown to induce ferroelectricity. A significant influence electric field cycling on both polarization as well small-signal capacitance-voltage measurements can be observed. X-ray diffraction are supported by infrared absorption analysis and give further evidence the previously proposed non-centrosymmetric transition phase space group Pbc21.
For the rather new hafnia- and zirconia-based ferroelectrics, a lot of questions are still unsettled. Among them is electric field cycling behavior consisting (1) wake-up, (2) fatigue, (3) recently discovered subcycling-induced split-up/merging effect transient current peaks in hysteresis measurement. In present work, first-order reversal curves (FORCs) applied to study evolution switching backswitching distribution within frame Preisach model for three different phenomena: The pristine film...
The origin of the ferroelectric polarization switching in orthorhombic HfO2 has been investigated by first principles calculations. phenomenon can be regarded as being coordinated displacement four O ions unit cell, which lead to a saturated high 53 μC/cm2. We show correlation between computed reversal barrier and experimental coercive fields.
In this study, the changes in structural and electrical properties of ferroelectric Hf1-xZrxO2 films with various Zr contents (0.26-0.70) were systematically examined during electric field cycling, resulting a "wake-up" effect. To quantify degree wake-up effect, "variable" polarization as difference between remanent saturation was suggested new parameter, which could be calculated by excluding linear dielectric contribution from total displacement. Here, variable value minimized for an...