A5010928788- Ferroelectric and Negative Capacitance Devices
- Semiconductor materials and devices
- Advanced Memory and Neural Computing
- Advancements in Semiconductor Devices and Circuit Design
- Ferroelectric and Piezoelectric Materials
- MXene and MAX Phase Materials
- Electronic and Structural Properties of Oxides
- Magnetic properties of thin films
- Semiconductor materials and interfaces
- Magnetic Properties and Applications
- Solid-state spectroscopy and crystallography
- Multiferroics and related materials
- Advanced Surface Polishing Techniques
- Diamond and Carbon-based Materials Research
- Molecular Junctions and Nanostructures
- Crystal Structures and Properties
- Conducting polymers and applications
- Metallic Glasses and Amorphous Alloys
- Magnetic Properties of Alloys
- Quantum and electron transport phenomena
- Advanced Materials Characterization Techniques
- Quantum-Dot Cellular Automata
- Silicon Carbide Semiconductor Technologies
- Ga2O3 and related materials
- Geomagnetism and Paleomagnetism Studies
University of California, Berkeley
2016-2025
Massachusetts Institute of Technology
2024-2025
Material Sciences (United States)
2021-2022
Nagoya University
2016
Lawrence Berkeley National Laboratory
2016
The critical size limit of voltage-switchable electric dipoles has extensive implications for energy-efficient electronics, underlying the importance ferroelectric order stabilized at reduced dimensionality. We report on thickness-dependent antiferroelectric-to-ferroelectric phase transition in zirconium dioxide (ZrO2) thin films silicon. emergent ferroelectricity and hysteretic polarization switching ultrathin ZrO2, conventionally a paraelectric material, notably persists down to film...
The persistence of voltage-switchable collective electronic phenomena down to the atomic scale has extensive implications for area- and energy-efficient electronics, especially in emerging nonvolatile memory technology. We investigate performance a ferroelectric field-effect transistor (FeFET) based on sliding ferroelectricity bilayer boron nitride at room temperature. Sliding represents different form atomically thin two-dimensional (2D) ferroelectrics, characterized by switching...
We report on negative capacitance FETs (NCFETs) with a 1.8-nm-thick Zr-doped HfO <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> gate oxide layer fabricated an FDSOI wafer. Hysteresis-free operation is demonstrated. When compared to baseline that uses the same thickness, subthreshold swing (SS) steeper by more than 20 mV/decade and larger 10X reduction in OFF current ( <inline-formula xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math...
Abstract In ferroelectric materials, spontaneous symmetry breaking leads to a switchable electric polarization, which offers significant promise for nonvolatile memories. particular, tunnel junctions (FTJs) have emerged as new resistive switching memory exploits polarization‐dependent current across thin barrier. This work integrates FTJs with complementary metal‐oxide‐semiconductor‐compatible Zr‐doped HfO 2 (Zr:HfO ) barriers of just 1 nm thickness, grown by atomic layer deposition on...
Analog reservoir computing (ARC) systems have attracted attention owing to their efficiency in processing temporal information. However, the distinct functionalities of system components pose challenges for hardware implementation. Herein, we report a fully integrated ARC that leverages material versatility ferroelectric-to-mixed phase boundary (MPB) hafnium zirconium oxides onto indium-gallium-zinc oxide thin-film transistors (TFTs). MPB-based TFTs (MPBTFTs) with nonlinear short-term memory...
The spin-orbit torque switching of ferrimagnetic Gdx(Fe90Co10)100−x films was studied for both transition metal (TM)-rich and rare earth (RE)-rich configurations. driven magnetization follows the same sense in TM-rich RE-rich samples with respect to total magnetization, but is reversed TM magnetization. This indicates that sign spin-orbit-torque-driven magnetic although transport based techniques such as anomalous Hall effect are only sensitive These results provide important insight into...
In this work, we present an experimental demonstration of a content addressable memory (CAM) cell based on ferroelectric HfO <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> field effect transistors (FeFETs). Our proposed CAM (FeCAM) utilizes CMOS-compatible material, hafnium zirconium oxide (HZO), as the gate dielectric. We discuss operation FeCAM and propose suitable architecture to realize in-memory computation well single clock cycle...
In this work, we demonstrate highly scaled, non-volatile memory transistors with ferroelectric Zr-doped HfO <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> (HZO) as gate insulator. <inline-formula xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">${\Omega }$ </tex-math></inline-formula> -gate length ~30 nm and width ~85 were fabricated on ~20 thick SOI. We robust operation ≤100 ns program erase speed at ±5 V,...
Scandium nitride (ScN) by plasma-enhanced atomic layer deposition (PEALD) was demonstrated on silicon (100), sapphire (0001), and magnesium oxide (001) substrates under ultrahigh purity conditions using a new Sc precursor, bis(ethylcyclopentadienyl)scandium-chloride [ClSc(EtCp)2]. Out-of-plane x-ray diffraction patterns indicated single-crystal, cubic phase ScN deposited at 215 °C (0001) substrates, whereas phi-scans confirmed epitaxial growth. The thin films grown with native were...
Strain engineering has been widely employed to control and enhance the ferroelectric properties of hafnium oxide (HfO₂)-based thin films. While previous studies focused on influence strain in simple metal-ferroelectric-metal structures, integration strain-induced ferroelectricity into field-effect transistors (FETs) requires consideration geometrical factors, such as interfaces between channel source/drain contacts, well device dimension. Here, we demonstrate effects HfO₂-based FETs (FeFETs)...
We report Negative Capacitance nFETs with a ~ 1 nm effective oxide thickness (EOT) gate stack. Experimental measurements show clear steepening of the slope I <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">D</sub> -V xmlns:xlink="http://www.w3.org/1999/xlink">G</sub> characteristic in weak inversion regime, indicating that capacitance matching takes place there. This leads to non-linear behavior current log scale, which is not observed...
Abstract Ferroelectric (FE) materials are key to advancing electronic devices owing their non‐volatile properties, rapid state‐switching abilities, and low‐energy consumption. FE‐based used in logic circuits, memory‐storage devices, sensors, in‐memory computing. However, the primary challenge practical applications of memory is its reliability. To address this problem, a novel polarization pruning (PP) method proposed. The PP designed eliminate weakly polarized domains by applying an...
With increasing applications for voltage-controlled magnetism, the need to more fully understand magnetoelectric coupling and strain transfer in nanostructured multiferroic composites has also increased. Here, nanocomposites were synthesized using block copolymer templating create mesoporous cobalt ferrite (CFO), followed by partly filling pores with ferroelectric zirconium-substituted hafnia (HZO) atomic layer deposition (ALD) produce a porous composite enhanced mechanical flexibility. Upon...
In ferroelectric materials, spontaneous symmetry breaking leads to a switchable electric polarization, which offers significant promise for nonvolatile memories. particular, tunnel junctions (FTJs) have emerged as new resistive switching memory exploit polarization-dependent current across thin barrier. Here we demonstrate FTJs with CMOS-compatible Zr-doped HfO$_2$ (Zr:HfO$_2$) barriers of just 1 nm thickness, grown by atomic layer deposition on silicon. These Zr:HfO$_2$ exhibit large...
Abstract The discovery of ferroelectricity in hafnia‐based materials has revitalized interest realizing ferroelectric field‐effect transistors (FeFETs) due to its compatibility with modern microelectronics. Furthermore, low‐temperature processing by atomic layer deposition offers promise for monolithic three‐dimensional (M3D) integration toward energy‐ and area‐efficient computing paradigms. However, integrating ferroelectrics channel FeFETs M3D remains challenging the dual requirement a...
Measurements on ultrathin body negative-capacitance (NC) field-effect transistors are shown to display subthreshold behaviors that cannot be explained as a classical MOSFET. Subthreshold swing (SS) at low drain bias decreases with increased gate for devices measured over multiple lengths down 30 nm. In addition, improvement in the SS relative control shows nonmonotonic dependence length. Using Landau-Khalatnikov ferroelectric (FE) model calibrated Capacitance-Voltage and combining it TCAD...
Ferroelectric Field Effect Transistors (FeFETs), where a ferroelectric material is placed on the gate of transistor has seen resurgence in recent years with advent doped HfO <inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</inf> as [1]. Here we will discuss potential and challenges for FeFETs memory solution near-memory in-memory computing. The ability to integrate oxide high-performance Si channels means that fast READ speed achievable. In...