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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]

Solution deposition of high-quality dielectric films is one of the big challenges in achieving excellent electrical performance of bi-layer solution-processed metal oxide (MO) thin film transistors (TFTs). Using an oxygen-doped precursor solution (ODS), we successfully deposited high-quality zirconium oxide (ZrO2) dielectric films by a solution process. The ODS-ZrO2 films show low leakage current density (10−7 A cm−2 at 2 MV cm−1), high breakdown electric field (7.0 MV cm−1) and high permittivity (19.5). Consequently, solution-processed indium oxide (In2O3) TFTs with ODS-ZrO2 film as the gate dielectric show excellent electrical performance, for example high carrier mobility up to 62.02 cm2 V s−1, a large on/off drain current ratio of 3.0 × 106, a small subthreshold swing of 0.14 V and excellent bias stress stability. Our work demonstrates the critical role of the dielectric film in the electrical performance of MO-TFTs. More importantly, we reveal that high dielectric constant (κ) dielectric film deposited with ODS should be an effective way to significantly increase the electrical properties of MO-TFTs for future low-cost, high-performance applications. [ABSTRACT FROM AUTHOR]

Low-power, form-free electronics require low-temperature and solution-processed high-κ dielectric materials with extremely low leakage current and good flexibility, which is still very challenging. For example, the large band-gap material La2O3 has been hampered from low-power electronics applications due to the poor stability and inability to be solution-processed. Here, we develop oxygen-incorporated solution-deposition to obtain a high-κ La2O3 dielectric film at a low temperature (120 °C). The thin film exhibits a uniform large area, a high-κ value (>12), a large band gap (>6.3 eV), a high breakdown electric field (>7 MV cm−1), and a very low leakage current (10−8 A cm−2 at 1 MV cm−1) with excellent and stable insulating characteristics comparable with ALD deposited films. This method efficiently improves the chemical reaction and wettability of the precursor solution for densification and is also applicable for other high-κ dielectric materials like HfO2 and ZrO2. The film endures compressive strain at the limit of the PET substrate (∼2.5%) and enables flexible CMOS circuits with stable organic thin-film transistors (OTFTs) that exhibit a high gain (>90), a low operation voltage (2 V), and a low static power consumption (∼0.5 nW). The excellent characteristics enable the presented film and method to generally advance low-power and high-performance electronics with printable and flexible properties. [ABSTRACT FROM AUTHOR]

Write‐once‐read‐many (WORM) memory behavior is often observed in polymer electret memory (PEM) devices, greatly limiting their overall performance. This paper systematically investigates the device physics of PEM devices with poly(α‐methylstyrene) as a charge trapping layer and pentacene as a semiconductor channel. The combined experiments on transistors, capacitances, and optical spectroscopy reveal that both the WORM memory behavior after negative and positive pulses and the gradual formation of memory after the continuous scanning are the results of the deficiency in minority (electrons) transport and trapping. Corresponding quantitative models are established and well explain the two‐stage, gradual trapping processes to form memory. By reducing the structural disorder and lateral channel length, ambipolar, bistable memory and much faster formation of memory window is obtained based on the same PEM device. The insights into device physics of PEM devices are expected to facilitate the design of organic, nonvolatile memory devices with high programming and erasing efficiencies. [ABSTRACT FROM AUTHOR]

High‐quality dielectric films are indispensable for field‐effect electronic devices to provide high electrical performance. However, deposition of high‐quality dielectric films on flexible substrate remains a challenging task, which greatly limits the electrical performance of flexible or organic field‐effect devices. A room‐temperature deep ultraviolet (DUV) irradiation process is proposed for densification of solution‐processed La2O3 films. It is found that room‐temperature DUV‐La2O3 films not only exhibit leakage and dielectric properties that are comparable to those of high‐temperature annealed‐La2O3 films, but also have very smooth and clean surfaces and excellent bending strain tolerance. The fabricated La2O3 films exhibit a wide band gap (5.78 eV), high dielectric constant (12.68), low leakage density (8.8 × 10−7 A cm−2 at 2 MV cm−1), and high breakdown field strength (3.5 MV cm−1). Organic thin‐film transistors (OTFTs) based on high‐quality solution‐processed La2O3 gate dielectrics show a low operation voltage (≤3 V), low gate leakage current (<10−9 A), and high Ion/Ioff ratio (>105). Based on these room‐temperature‐fabricated high‐performance OTFTs, low‐voltage complementary integrated circuits are successfully fabricated, including complementary inverters and NAND gate circuits. The results demonstrate that room‐temperature DUV‐processed La2O3 films are ideal gate dielectric materials for future flexible and low‐power‐consumption electronic devices. [ABSTRACT FROM AUTHOR]