A5026779977- Ferroelectric and Negative Capacitance Devices
- Semiconductor materials and devices
- MXene and MAX Phase Materials
- Advanced Memory and Neural Computing
- Physical Unclonable Functions (PUFs) and Hardware Security
- Quantum-Dot Cellular Automata
- Advanced Sensor and Energy Harvesting Materials
- Electronic and Structural Properties of Oxides
Korea Advanced Institute of Science and Technology
2022-2025
This article presents a 3D ferroelectric NAND flash memory with wide MW, low operation voltage, fast PGM/ERS speed, and higher endurable cycles based on HfZrO film that shows excellent ferroelectricity even at relatively thick thickness.
This study proposes a self-rectifying ferroelectric tunnel junction (SR-FTJ) crosspoint array to satisfy the stringent size requirements of Internet-of-Things devices. Each cell in SR-FTJ consists two SR-FTJs stacked vertically, resulting ultrahigh density. The can operate as: 1) ternary content-addressable memory (TCAM) or 2) binary content addressable (BCAM) physically unclonable function (PUF) dual-mode operation. In operation, amount current flowing through remains same, stable PUF...
Recently, hafnia-based ferroelectrics are currently being investigated as next-generation memory devices due to their excellent CMOS process compatibility and functionality. However, some of the ferroelectric commonly exhibit an imprint effect charged defects around interfacial layer, which has negative impacts on devices. it can be applied various applications long field is carefully adjusted. In this work, we introduced a strategy control in bilayer capacitors by utilizing tantalum oxide...
Ferroelectric field-effect transistors (FeFETs) have attracted enormous attention for low-power and high-density nonvolatile memory devices in processing-in-memory (PIM). However, their small window (MW) limited endurance severely degrade the area efficiency reliability of PIM devices. Herein, we overcome such challenges using key approaches covering from material to device array architecture. High ferroelectricity was successfully demonstrated considering thermodynamics kinetics, even a...
In this work, we demonstrate a novel approach to superior multilevel-cell (MLC) ferroelectric field-effect transistor (FeFET) with large memory window (MW) and negligible <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">${V}_{T}$ </tex-math></inline-formula> variation toward MLC operation. We realized high ferroelectricity in relatively thick HZO (FE) layer for FeFET MW [MW notation="LaTeX">$\propto $...
Abstract Flash memory is a promising candidate for use in in‐memory computing (IMC) owing to its multistate operations, high on/off ratio, non‐volatility, and the maturity of device technologies. However, operation voltage, slow speed, string array structure severely degrade energy efficiency IMC. To address these challenges, novel negative capacitance‐flash (NC‐flash) memory‐based IMC architecture proposed. stabilize utilize capacitance (NC) effect, HfO 2 ‐based reversible single‐domain...
Hafnia-based ferroelectric materials are recently drawing a significant attention for future electronic devices; however, there is need to further enhance their functionality practical applications. Especially, an imprinting effect has been regarded as defect be reduced in ferroelectrics; yet, it can positively applied various devices with the of self-rectifying behavior and threshold voltage adjustment. For first time, we report high bilayer stack capacitors [TiN/Hf0.5Zr0.5O2 (HZO)/tantalum...
This study proposes a self-rectifying ferroelectric tunnel junction (SR-FTJ) crosspoint array which affords dual-mode operation as content-addressable memory (CAM) and physically unclonable function (PUF). The PUF mode of the proposed SR-FTJ does not require any temporary transfer stored CAM data to buffer, prevents additional area overhead or potential security threats. Experimental measurements verify feasibility operation. Further simulations using model reflecting measured...
We provide a methodology for designing thermally stable hafnia ferroelectric (FE) materials to be taken into account while fabricating 3D memory devices. reveal the underlying origins thermal instability of FE in terms kinetics and material science. Furthermore, we suggest adopting dopants whose ionic radius is smaller than Hf matrix as feasible option demonstrate material. Using this approach, robust ferroelectricity achieved even at subsequent budget (TB) 750 °C 30 min. The improved...
The effect of negative capacitance (NC), which can internally boost the voltage applied to a transistor, has been considered overcome fundamental Boltzmann limit transistor. To stabilize NC effect, dielectric (DE) must be integrated into heterostructure with ferroelectric (FE) film. However, in multidomain hafnia, charge boosting is reduced owing lowering depolarization field originating from stray at each domain, and simultaneously, operating increases division DE. Here, we demonstrate core...