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Resistive switching memories have garnered significant attention due to their high‐density integration and rapid in‐memory computing beyond von Neumann's architecture. However, significant challenges are posed in practical applications with respect to their manufacturing process complexity, a leakage current of high resistance state (HRS), and the sneak‐path current problem that limits their scalability. Here, a mild‐temperature thermal oxidation technique for the fabrication of low‐power and ultra‐steep memristor based on Ag/TiOx/SnOx/SnSe2/Au architecture is developed. Benefiting from a self‐assembled oxidation layer and the formation/rupture of oxygen vacancy conductive filaments, the device exhibits an exceptional threshold switching behavior with high switch ratio exceeding 106, low threshold voltage of ≈1 V, long‐term retention of >104 s, an ultra‐small subthreshold swing of 2.5 mV decade−1 and high air‐stability surpassing 4 months. By decreasing temperature, the device undergoes a transition from unipolar volatile to bipolar nonvolatile characteristics, elucidating the role of oxygen vacancies migration on the resistive switching process. Further, the 1T1R structure is established between a memristor and a 2H‐MoTe2 transistor by the van der Waals (vdW) stacking approach, achieving the functionality of selector and multi‐value memory with lower power consumption. This work provides a mild‐thermal oxidation technology for the low‐cost production of high‐performance memristors toward future in‐memory computing applications. [ABSTRACT FROM AUTHOR]

Hf0.5Zr0.5O2 (HZO) thin films are promising for applications in ferroelectric memories. However, these materials often face challenges, such as polarization fluctuations (e.g., fatigue and wake-up) and electric break-down incidents during the "1/0" write/read cycles, hindering their industrial application. Herein, fatigue, wake-up, and electric break-down seriously depend on both the electric field for polarization switching (Es) and the charge accumulation in the HZO film. More and more charges pin ferroelectric domains, and the sub-switching polarization introduces serious ferroelectric fatigue during the 1010 write/read cycles at Es ∼ 1.2Ec, where Ec is a ferroelectric coercive field. On the contrary, new charges increase rather slowly, and complete polarization switching is realized during the 1010 cycles at Es ∼ 1.5Ec, so the HZO film presents excellent polarization stability. A high Es ∼ 2Ec introduces the strong wake-up effect first; however, the serious charge accumulation largely increases leakage current and quickly introduces an electric break-down of the HZO film. Furthermore, it was found that the leakage current and dielectric permittivity can effectively monitor the charge accumulation and provide an early warning for fatigue and electric break-down. [ABSTRACT FROM AUTHOR]

Dielectric capacitors are widely used in pulsed power electronic devices due to their ultrahigh power densities and extremely fast charge/discharge speed. To achieve enhanced energy storage density, maximum polarization (Pmax) and breakdown strength (Eb) need to be improved simultaneously. However, these two key parameters are inversely correlated. In this study, order–disorder transition induced polar nanoregions have been achieved in PbZrO3 thin films by making use of the low-energy ion implantation, enabling us to overcome the trade-off between high polarizability and breakdown strength, which leads to the tripling of the energy storage density from 20.5 to 62.3 J/cm3 as well as the great enhancement of breakdown strength. This approach could be extended to other dielectric oxides to improve the energy storage performance, providing a new pathway for tailoring the oxide functionalities. [ABSTRACT FROM AUTHOR]

The endurance limitation related to high coercive fields (${E}_{\text{c}}$) has been one of the substantial challenges to future memory applications of ferroelectric HfO2 films. In this work, we demonstrate a simple, efficient, and accurate method to regulate the ${E}_{\text{c}}$ value of Hf0.5Zr0.5O2 (HZO) films via interface modification through ultraviolet-ozone (UV-O3) irradiation on the surface of bottom electrode. Growth behaviors and ferroelectricity of HZO films were systematically investigated by varying UV-O3 irradiation time. HZO samples show a well-controlled ${E}_{\text{c}}$ upon a suitable UV-O3 irradiation time. Compared with the $w/o$ sample, the ${E}_{\text{c}}$ value of 30-min irradiated sample drops by ~29.5%, and a comparatively high $2{P}_{r}$ of 28.6 $\mu \text{C}$ /cm2 remains. The tuning of ${E}_{\text{c}}$ is clarified to be due to the ratio change of orthogonal and tetragonal phases in HZO films, which can be well controlled by the change of surface energy of the bottom electrode via varying the UV-O3 irradiation time. [ABSTRACT FROM AUTHOR]

In this work, we systematically investigated the carrier transport of hysteresis-free amorphous InGaZnO (a-IGZO) thin film transistors (TFTs) incorporating high- k (HfO2) x (Al2O3) y gate dielectrics with different composition and permittivity by atomic layer deposition. A dielectric surface morphology dominated interface scattering carrier transport mechanism is demonstrated, and the effect of the dielectric polarization and the interface states on the carrier mobility is discovered in TFT devices gated by high quality dielectrics with negligible charge trap effect. Accordingly, an a-IGZO TFT gated by (HfO2)0.5(Al2O3)0.5 dielectric with the smoothest surface exhibits the best performance in terms of a preferable field-effect mobility of 18.35 cm2 Vâˆ'1 sâˆ'1, a small subthreshold swing of 0.105 V decadeâˆ'1, a high on/off current ratio of 4.6 Ă— 106, and excellent stability under positive bias stress. [ABSTRACT FROM AUTHOR]