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In this paper, we designed double V-shaped Al/Ni multilayer energy-containing microdevices with different V-angles, and we performed finite element modeling and simulation of the heat transfer process of the designed energy-containing microdevice. Temperature-dependent resistivity was introduced to effectively simulate the phase change during ignition. We simulated the temperature and current density distribution in the central region of the Al/Ni multilayer energy-containing microdevice and predicted the ignition voltage threshold for the specific device structure. Al/Ni multilayer energy-containing microdevices with different V-angles were prepared by electron beam evaporation technology, and ignition experiments on the prepared devices under the excitation of 47 μF capacitance were conducted. The experimental results show that the critical voltage of ignition increases with the increase in the V-angle, which verifies the correctness of the proposed finite element model. [ABSTRACT FROM AUTHOR]

In application scenarios such as astronautics, high-altitude aircraft, medical radiography, high-energy physics, and nuclear power plants, the irradiation resistance of electronic components is one of the basic requirements for their reliability. HfO 2 -based ferroelectric films have the advantages of high CMOS process compatibility, good miniaturizability, low operating voltage, and excellent irradiation resistance, which are the core materials for the new generation of irradiation resistance ferroelectric memories. In this paper, two kinds of metal-electrode ferroelectric capacitors, W/Hf 0.5 Zr 0.5 O 2 /W (WW) and Pt/Hf 0.5 Zr 0.5 O 2 /Pt (PP), have been prepared, and three gradient γ-irradiation experiments have been carried out on the two kinds of ferroelectric capacitors. The effect of metal electrodes on the irradiation resistance of Hf 0.5 Zr 0.5 O 2 ferroelectric thin films was carefully investigated by comparing and analyzing the statistical laws of polarization change and rectangularity change before and after irradiation of a large number of devices. The experimental results show that the WW devices have better irradiation resistance than PP devices, and we further explain the irradiation resistance mechanism by first-principle calculations and finite element analysis to verify the credibility of the experimental results. Finally, we conducted a comparative test of the fatigue and wake-up characteristics of the WW devices before and after irradiation, and the results show that the prepared W/Hf 0.5 Zr 0.5 O 2 /W devices can withstand very high total γ-dose radiation, reaching up to 13.86 Mrad(Si), and they are very suitable for the application of irradiation resistant electronics. [Display omitted] • The Hf 0.5 Zr 0.5 O 2 (HZO) thin films with outstanding ferroelectric properties were prepared. • The HZO ferroelectric thin films exhibited extremely high radiation tolerance (reaching up to 13.86 Mrad(Si)). • The effect of different metal electrodes on the irradiation resistance of HZO ferroelectric thin films was analyzed. [ABSTRACT FROM AUTHOR]

The oxygen ion (O2−) loss effect during resistive switching (RS) cycles will inevitably lead to endurance degradation or even failure in oxide-based memristive devices. In this Letter, we propose an effective way to recover the cycling-induced endurance failed HfOx based memristive devices by utilizing oxygen plasma treatment (OPT). In the as-fabricated Pt/HfOx/Pt devices, a negative SET event is observed after consecutive normal RS cycles and eventually triggers endurance failure. The appearance of the intermediate resistance state at the initial stage of the negative SET cycle indicates a prominent reduction of the migration barrier of O2−, which accounts for the occurrence of negative SET after increasing cycles. Then, we recover the devices from endurance failure by moderate OPT, which can supply the available O2− in RS cycles. More importantly, the first recovered devices after endurance failure can be recovered again through OPT, which better proves the validity of the recovery method. This study could provide an effective approach for understanding and addressing the cycling-induced endurance failure issue in oxide-based memristive devices. [ABSTRACT FROM AUTHOR]

• Monolayer MoO 3 /MoO x were prepared by plasma oxidation and atomic layer etching. • The proposed process can precisely control the thickness of molybdenum oxide. • The prepared monolayer molybdenum oxide has good surface morphology and uniformity. In this letter, we propose two different methods to prepare monolayer MoO 3 and MoO x by low-temperature inductively coupled plasma etching technology. The monolayer MoO 3 is obtained by soft oxygen plasma oxidation of monolayer MoS 2 due to the high specific surface area. The monolayer MoO x is prepared through plasma oxidation and atomic layer-by-layer etching of multilayer MoS 2 due to the weak van der Waals interaction between the layers. It is proved that the prepared monolayer molybdenum oxide has good surface morphology and highly controllable components. The proposed process can precisely control the thickness of molybdenum oxide and has good uniformity and higher selectivity. This work could promote the application of atomically thin transition metal oxides in two-dimensional materials based electronic devices and its integration. [ABSTRACT FROM AUTHOR]

Oxygen ions' migration is the fundamental resistive switching (RS) mechanism of the binary metal oxides-based memristive devices, and recent studies have found that the RS performance can be enhanced through appropriate oxygen plasma treatment (OPT). However, the lack of experimental evidence observed directly from the microscopic level of materials and applicable understanding of how OPT improves the RS properties will cause significant difficulties in its further application. In this work, we apply scanning probe microscope (SPM)-based techniques to study the OPT-enhanced RS performance in prototypical HfOx based memristive devices through in situ morphology and electrical measurements. It is first found that the structural deformations in HfOx nanofilm induced by migration of oxygen ions and interfacial electrochemical reactions can be recovered by OPT effectively. More importantly, such structural deformations no longer occur after OPT due to the strengthening in lattice structure, which directly illustrates the enhanced quantity of HfOx nanofilm and the nature of enhanced RS properties after OPT. Finally, the underlying mechanisms of OPT-enhanced RS performance are analyzed by the results of X-ray photoelectron spectroscopic (XPS) surface analysis. In the OPT-enhanced HfOx nanofilm, oxygen vacancies in crystalline regions can be remarkably reduced by active oxygen ions' implantation. The oxygen ions transport will depend considerably on the grain boundaries and OPT-enhanced lattice structure will further guarantee the stability of conductive filaments, both of which ensure the uniformity and repeatability in RS processes. This study could provide a scientific basis for improving RS performance of oxides-based memristive devices by utilizing OPT. [ABSTRACT FROM AUTHOR]

The γ‐ray total dose radiation effects on Zr‐doped HfO2 (HfZrO) and Al‐doped HfO2 (HfAlO) ferroelectric thin films are comparatively studied. The J–E, P–E,C–V, εr–f curves and fatigue characteristics of both HfZrO and HfAlO thin films are measured and analyzed with the increasing total dose from 0 to 5 Mrad (Si). The remnant polarization (Pr) values of both HfZrO and HfAlO thin films first decrease and then increase with the increasing total dose. A competitive mechanism between the pinned domains and increasing polarization switching charges induced by radiation is proposed to explain this phenomenon. This work presents doped HfO2 film with great radiation tolerance for nuclear and aerospace applications. [ABSTRACT FROM AUTHOR]

Bi4Ti2.99Mn0.01O12 (BTM) thin films with different ratio of neodymium (Nd) doping were prepared on Pt(111)/Ti/SiO2/Si(100) substrates through a sol-gel method. The effects of Nd doping on domain dynamics and temperature-dependent fatigue behaviors of BTM thin films were systematically studied. The polarization fatigues of BTM (not doped) and Bi3.5Nd0.5Ti2.99Mn0.01O12 (BNTM05) thin films first get better with the increasing temperature (T) from 300 to 350 K and then become worse from 350 to 400 K, while Bi3.15Nd0.85Ti2.99Mn0.01O12 (BNTM85) thin films show enhanced fatigue endurance from 300 to 400 K. It can be shown that the long-range diffusion of oxygen vacancies in BTM thin film happens more easily through the impedance spectra analysis with T from 300 to 475 K, which can be verified by a lower activation energies (0.13–0.14 eV) compared to those of BNTM05 and BNTM85 (0.17–0.21 eV). Using a temperature-dependent piezoresponse force microscopy (PFM), we have found more responsive domain fragments in Nd-substituted films. The microscopic domain evolution from 298 to 448 K was done to further explain that the domain wall unpinning effect has been enhanced with increasing T. The correlation between microscopic domain dynamics and macroscopic electrical properties clearly demonstrates the effects of charged domain wall in Nd-doped BTM thin films during the fatigue tests. [ABSTRACT FROM AUTHOR]

The usage of ferroelectric-gate field effect transistors (FeFET) in digital circuits has typically been its applications in memory. The use of FeFET to implement logic circuits is neither completely understood nor extensively studied. This paper presents simulations of electrical properties of a single FeFET and the resulting behavioral characterizations of FeFET-based basic logic circuits in a commercially available TCAD environment. The all-FeFET current mirror, CMOS inverter, 2-input-NAND and 2-input-NOR logic circuits show almost the same electrical characteristics as standard MOSFET ones, except for the negligible clockwise hysteresis under the condition of low voltage supply. Moreover, the all-FeFET current mode sensitive amplifier whose component units were all-FeFET common-source amplifier, current mirror and differential amplification, also works reasonably. [ABSTRACT FROM AUTHOR]

A square 3D-Trench electrode Si detector structure is simulated using a 3D TCAD tool. Electrical characteristics including electrostatic potential, electric field, leakage current, and capacitance have been simulated in detail. It has been found in simulations that both leakage current and the voltage to reach the geometry capacitance (full depletion voltage, V fd ) increase with radiation fluence. The geometry capacitance is 99 fF for the standard structure in our study. Detector geometry capacitance׳s dependence on the length and area of the collection column has also been simulated. [ABSTRACT FROM AUTHOR]

3D-trench electrode detectors were simulated in this paper. Charge collection of 3D-trench electrode detector was simulated using the full 3D device simulation. The induced current and collected charge caused by drifting carriers, generated by a minimum ionizing particle (MIP) incident through the detector, have been modeled and calculated. The results indicate that the total collected charge in irradiated detector change with particle incident position and radiation fluence. In addition, we have estimated the average total collected charge generated by a MIP incident in 3D-trench electrode detector. [ABSTRACT FROM AUTHOR]

Perovskite ferroelectrics (FEs) have high endurance to radiation. Strontium titanate (STO) (SrTiO3) is a kind of perovskite FE with a large dielectric constant, which has attracted a good deal of attention due to its excellent dielectric, photoelectric and optical properties. The proton radiation damage in STO thin films is investigated by computer simulations in this work. The threshold displacement energy is an important input parameter for Monte Carlo simulation based on a binary collision approximation model, so we first use molecular dynamics to calculate the averaged threshold displacement energy of Sr, O and Ti atom. The calculated values are 67, 50 and 136 eV, which are obviously larger than default value (25 eV) in the Stopping and Range of Ions in Matter (SRIM) code. The results of the SRIM simulation demonstrate the dependency of vacancy number and position distribution on the proton's energy and the angle of incidence. [ABSTRACT FROM AUTHOR]

• This study explored the influence of thickness and temperature on the electrical properties of Pt / HfO 2 / Al 2 O 3 / TiN structure RRAM devices. • Adjust the performance of the device by adjusting the thickness of the double-layer film. • The results obtained have important guiding significance for one-step experimental application. Thin films with HfO 2 /Al 2 O 3 laminated structure were prepared by the ALD method in this paper. Typical bipolar resistance switching characteristics were observed in the Pt/HfO 2 /Al 2 O 3 /TiN structure device. The samples were characterized by X-ray photoelectron spectroscopy (XPS) and atomic force microscopy (AFM). The effects of dielectric thickness and different test temperatures on the electrical performance were investigated. Experiments show that when the thickness of HfO 2 /Al 2 O 3 is 7 nm/3 nm, the electrical properties are the best. As the test temperature increases, the resistance values (R LRS and R HRS) of the Pt/HfO 2 /Al 2 O 3 /TiN structure fluctuate more and more. When the test temperature approaches the failure temperature, the device's transition voltages (V Set and V Reset) will also become more volatile. [ABSTRACT FROM AUTHOR]

The friction behavior of monolayer molybdenum diselenide (MoSe 2) under normal electric field was studied by the atomic force microscope. The friction coefficients of MoSe 2 are increasing with bias voltage applied on the Si substrate. The results show that the adhesion and electrostatic forces increase with bias and approximately follow a parabolic law. The friction force and surface potential are of the same tendency with bias application time, and the contribution of charges accumulation to friction is considerable. The mechanisms of the friction behavior under external normal electric field were explained with electrostatic force and adsorption. This study reveals a possibility of electronically controlling friction in two-dimensional MoSe 2 system, with potential applications in solid lubricant and moving parts for MEMS devices. • The friction behavior of monolayer MoSe 2 nanosheet can be modulated under normal electric field investigated by the AFM. • The friction coefficient, adhesion force and electrostatic force increase with the sample bias. • The mechanisms of friction behaviors under normal electric field were explained with electrostatic force and absorption. • A possibility of electronically controlling friction is provided in 2D MoSe 2 system. [ABSTRACT FROM AUTHOR]

Total-ionizing dose effects on the resistive switching properties of HfO 2 /Al 2 O 3 bipolar resistive-random-access-memory devices under 60Co γ irradiation were investigated in this study. Insignificant impact was found for 60Co γ irradiation with a dose of 200 krad (Si) but the impact became significant for higher irradiation intensity of 1 Mrad (Si). The experiment results indicated that it is possible for device high resistance off-state or low resistance on-state to change after a total ionizing dose step stress threshold being surpassed. Moreover, it was found that the 60Co γ irradiation of 1 Mrad (Si) caused degradation of device high-resistance state, low-resistance state, set/reset voltages, and endurance characteristics, due to the simultaneous induce of oxygen vacancies and displacement damage. Unlabelled Image [ABSTRACT FROM AUTHOR]