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In this article, we have investigated the forming free bipolar resistive switching (RS) phenomena of ${e}$ -beam evaporated amorphous tin-oxide-based RS device with copper as a bottom electrode. To describe the impact of copper electrode over electrical response of tin-oxide-based RS device, we have used tungsten probe tip contact as a top electrode and copper as a bottom electrode. The crystal structure, energy bandgap, surface morphology, and device cross-sectional nanostructure view of deposited thin RS layer (tin-oxide) have been characterized by using X-ray diffraction (XRD), UV–visible spectroscopy, and field-emission scanning electron microscopy (FESEM), respectively. The electrical behavior of fabricated switching device has been recorded by Keithley-4200 parametric analyzer with customized probe station. Reported switching device has capability to perform reversible RS phenomena for 500 cycles with low set/reset (−0.52/0.39 V) voltage and good resistive window (~15) without any considerable degradation. We have also discussed the primary reason for RS dynamics in the proposed device along with its conduction mechanism. [ABSTRACT FROM AUTHOR]

Hole concentration of 2-D hole gas (2DHG) on (110) diamond is higher than that on other faces, making it the best choice for power device application. Detailed analysis of atomic layer deposition (ALD) Al2O3/(110) C–H diamond interface structure is of vital importance. MOSFETs with thin (10 nm) and thick (100 nm) ALD Al2O3 layer were made in this study. The microstructure of Al2O3 on (110) C–H diamond was analyzed. Abrupt interface of ALD Al2O3/C–H diamond was observed through high resolution transmission electron microscope (HRTEM). Cascode structure using diamond MOSFETs and enhancement mode silicon MOSFET is fabricated and its high performance is confirmed. [ABSTRACT FROM AUTHOR]

The gate conduction mechanisms in p-gallium nitride (GaN)/AlGaN/GaN enhancement mode transistors are investigated using temperature-dependent dc gate current measurements. In each of the different gate voltage regions, a physical model is proposed and compared to experiment. At negative gate bias, Poole–Frenkel emission (PFE) occurs within the passivation dielectric from gate to source. At positive gate bias, the p-GaN/AlGaN/GaN “p-i-n” diode is in forward operation mode, and the gate current is limited by hole supply at the Schottky contact. At low gate voltages, the current is governed by thermionic emission with Schottky barrier lowering in dislocation lines. Increasing the gate voltage and temperature results in thermally assisted tunneling (TAT) across the same barrier. An improved gate process reduces the gate current in the positive gate bias region and eliminates the onset of TAT. However, at high positive gate bias, a sharp increase in current is observed originating from PFE at the metal/ p-GaN interface. Using the extracted conduction mechanisms for both devices, accurate lifetime models are constructed. The device fabricated with the novel gate process exhibits a maximum gate voltage of 7.2 V at ${t}_{\textsf {1}\%}=\textsf {10}$ years. [ABSTRACT FROM AUTHOR]

The electrical conduction mechanisms of Ni-Cr thin film resistor are demonstrated by different film thickness through scattering models fitting. The resistivity and temperature coefficient of the resistance of Ni-Cr thin film are measured to investigate the influence of thickness with different annealing temperature. Finally, an oxidation and atom inter-diffusion model was proposed to explain the effects of film thickness on the electrical properties of Ni-Cr thin film resistor under different annealing temperature.

In this work, the impact of the diameter on vertical nanowire tunnel field effect transistors is analyzed focusing on the conduction mechanism and analog parameters, considering different conduction regimes. The diameter influence is investigated using experimental and simulation data. The impact of the diameter on the analog parameters is analyzed, considering both weak and strong conduction. For a smaller diameter, the impact of band-to-band tunneling (BTBT) on the device characteristics increases, showing opposite trends for weak and strong conduction. For strong conduction, a degradation of the intrinsic voltage gain occurs for very small diameters, because the device has less available area for the occurrence of tunneling. For weak conduction, the reduction of the diameter increases the BTBT along the channel/source junction without showing this degradation. [ABSTRACT FROM PUBLISHER]

HfLaO and HfO2 films were deposited by plasma enhanced atomic layer deposition (PEALD). PEALD makes in-situ plasma treatment possible, and the film growth temperature can be reduced. The films were characterized. High resolution transmission electron microscopy (HRTEM) indicated both films were amorphous. X-ray photoelectron spectroscopy (XPS) suggested that the interface layer was most likely composed of Hf-Si-O and La-Si-O. MIS capacitors with HfLaO and HfO2 dielectrics were irradiated by gamma rays with the dose up to 2\times 10^6~rad (Si). Electrical measurements indicated that the dielectrics showed relatively stable electrical properties. The equivalent oxide thicknesses (EOT) of HfLaO samples were calculated to be 0.9 nm. At a gate condition of \vertVg\mathchar"702D Vfb\vert=1~\rm V, the leakage current densities were 0.02 \ mA/\ cm^2. With the increasing of the radiation dose, the maximum oxide trap charge density and interface trap charge density for HfLaO samples were calculated to be 2.6\times 10^12~\ cm^-2 and 1.2\times 10^12~\ cm^-2, respectively. The analysis of the IV curves suggested that the conduction mechanism in HfLaO samples is the Poole-Frenkel emission. [ABSTRACT FROM PUBLISHER]

We report nonvolatile resistive switching in anodic niobium pentoxide thin-film memory cells. Highly dielectric \Nb2\O5 films were prepared at room temperature by the anodic oxidation of submicrometer-thick Nb films sputtered onto an Si wafer. After the electroforming process, \Au/Nb2\O5/\Nb/Si sandwich memory cells demonstrate reproducible direct current and pulse mode switching between two resistance states with a resistance on-off ratio around \10^3. Low and high resististive states show ohmic conductivity and field-assisted Poole–Frenkel-type conductivity, respectively. Nonvolatile resistance storage was traced within 40 days to quantify retention characteristics of the \Nb2\O5 memristor. The low-temperature anodic oxidation of Nb was found to be feasible to fabricate high-density cross-point memory with 3-D stack structures. [ABSTRACT FROM AUTHOR]

The mechanisms of conduction and dielectric loss pertaining to electrical insulating oils, are examined with specific reference to the conduction and dielectric loss processes involving ionic and macroscopic particle charge carriers. Specific examples are presented; one of the most serious types of conduction by particles is that due to semiconductive copper sulfide particles, which are formed in a reaction between copper conductors or copper particles and the corrosive sulfur components contained in the oils. [ABSTRACT FROM AUTHOR]

In this paper, nonpolar resistive switching behavior is reported for the first time in a SZO-based memory device. The electrode materials used which have different conductivities affect the resistive switching properties of the device. The AI/V:SZO-LNO/Pt device shows nonpolar switching behavior, whereas the AI/V:SZO/LNO device has bipolar switching property. The resistance ratios of these two devices are quite distinct owing to the difference between the resistance of low resistance states. The AI/V:SZO-LNO/Pt device with lower resistive switching voltages (±7 V turn on and ±2 V turn off) and higher resistance ratio (107) is more suitable for practical applications compared to the AI/V:SZO/LNO device. The switching speed of the AI/V:SZO-LNO/Pt device is 10 ns, which is the fastest speed that has ever been reported. The conduction mechanisms, nondestructive readout property, retention time, and endurance of this device are also reported in this paper. [ABSTRACT FROM AUTHOR]

The real-time conduction mechanism during bias stress of three silica-based intermetal dielectrics in Cu damascene structures was investigated. High-frequency capacitance and I-V measurements were intermittently inserted into the process of bias stress to monitor the conduction mechanism change with time. All experiments show that the capacitance is constant, and the I-V curve slope decreases with bias stress and converges to half of the initial value. Based on an extended Frenkel-Poole model with compensation effects, we propose that the changes of the acceptor/donor densities in the dielectrics result in the apparent I-V curve slope evolution, but the dominant conduction mechanism is always bulk controlled. [ABSTRACT FROM PUBLISHER]

The incorporation of nanometer pores into a low-dielectric constant (low-k) aromatic hydrocarbon polymer significantly degrades the electrical characteristics and breakdown strength of the material. Enhanced electric field in the pores increases the probability of bond breakage on the pore walls and leads to the lowering of the overall breakdown strength. [ABSTRACT FROM AUTHOR]

This letter investigates the low-temperature switching characteristics and conduction mechanism of the Pt/HfOx/TiN resistive random access memory devices. For the first time, Pt/HfOx/TiN devices were demonstrated to be well functional at ultralow temperature (4 K). The switching voltages slightly increase at lower temperature. The failure state in a breakdown sample shows a metallic behavior, while the normal low-resistance states and high-resistance states show a semiconducting behavior. The slope change in the 1/kT plot below 77 K indicates a transition from the nearest-neighboring hopping to the variable range hopping. Different slopes or activation energies are observed at the same resistance level in the same device but after different programming cycles, indicating a cycle-dependent variation of the filament configuration. [ABSTRACT FROM AUTHOR]

Perovskite-based BaZry\rm Ti1-y\rm O3 (BZTO) (y=0.6) with partial crystallization has been found to possess a rather high-\kappa value of 48.6 and positive quadratic voltage coefficient of capacitance (VCC). Through stacking BZTO and ZrTiOx as laminate dielectric, metal–insulator–metal capacitors using VCC canceling effect advance frontiers by exhibiting a record-low VCC of 14 ppm/V^2 at the capacitance of 13.4 fF/\mum^2, low dielectric loss tangent <0.01, and low leakage current of 7.5\times 10^-9~A/cm^2 at -1~V. With constant voltage stress at 2.5 V for 1000 s, degradation in leakage current <30\% is observed. In addition, excellent reliability of 0.89% capacitance change against stress up to a projected of 10 years is also achieved. The aforementioned characteristics not only compare favorably to other high-\kappa-based dielectrics, most importantly, but also these results meet ITRS requirements set by 2024. [ABSTRACT FROM AUTHOR]

Low-frequency noise (LFN) characteristics have been studied in polycrystalline-\TiOx-based resistive random access memories (RRAMs). LFNs are proportional to \1/f in high-resistance state (HRS), but those in low-resistance state (LRS) are proportional to \1/f only in less than \sim100 Hz. The normalized noise power in HRS is around three orders of magnitude higher than that in LRS. Bias dependence of \1/f noise shows that the current conduction mechanisms from noise measurements are consistent with those from the current–voltage relationships in \TiOx-based unipolar RRAM devices. [ABSTRACT FROM PUBLISHER]

Metal–insulator–metal (MIM) capacitors with crystalline- \TiO2/\SiO2 stacked dielectric are explored in this letter. The crystalline \TiO2 possesses a high permittivity while the \SiO2 provides a negative quadratic voltage coefficient of capacitance (VCC\-\alpha) to cancel out the positive VCC\-\alpha from the crystalline \TiO2. These desirable properties render MIM capacitors with high performance in terms of a capacitance density of 11.9 \fF/\mu\m^2 with a VCC\-\alpha of 90 \ppm/V^2. With additional \N2 plasma treatment on the crystalline \TiO2, because of the effective passivation of grain-boundary-related defects and, consequently, a lower leakage current by a factor of 50, the VCC\-\alpha can be further lowered to 30 \ppm/V^2 with slight degradation in capacitance density to 11.2 \fF/\mu\m^2, which well meets the requirement in 2018 set by ITRS. [ABSTRACT FROM PUBLISHER]

In this letter, a reliable nonvolatile resistive switching device based on silicon monoxide (SiO) is demonstrated. The device was fabricated with a low-temperature process that can be compatible with a CMOS back-end process and attractive for 3-D memory integration. The fabricated Cu/SiO/W device was found to have a repeatable unipolar resistive switching behavior. The results show excellent on/off resistance ratio (over 104) and good retention performance. The switching mechanism of the device is analyzed by experimental data and probably can be attributed to the behaviors of copper ions in the bulk of SiO under different voltages. [ABSTRACT FROM AUTHOR]

The resistive switching behaviors of sputtered V-doped SrZrO3 (V:SZO) memory films were investigated in this letter. The current states of the memory films were switched between high current state (H-state) and low current state (L-state). The resistance ratio of the two current states was over 1000 at a read voltage. The switching mechanism from L- to H-state corresponds to the formation of current paths. However, this mechanism from H- to L-state is thought to be due to the fact that the defects present in the V:SZO film randomly trap electrons, and hence, the current paths are ruptured. The conduction mechanism of the H-state is dominated by ohmic conduction, whereas the L-state conduction is dominated by Frenkel-Poole emission. The polarity direction of the resistive switching is an intrinsic property of the SrZrO3 oxides. The V:SZO films with high uniformity and good stability are expected to be used in nonvolatile memory. [ABSTRACT FROM AUTHOR]

Sputter-deposited Cr-doped SrZrO3 ebased metal-insulator-metal structures exhibited bistable resistive reversible switching as observed under bias voltage and voltage pulse. The ratio of resistance of the two leakage states (high-H, low-L) was about five orders of magnitude. The conduction of the L-state satisfied Frenkel-Poole emission and that of the H-state followed ohmic mechanism, causing the resistance ratio to decrease with increasing bias voltage. The transition time of H- to L-state was five orders of magnitude higher than that of L- to H-state. The transition from H- to L-state was the restricted part for reversible switching operation. The difference in transition time of the two states should be related to the respective conduction mechanisms. [ABSTRACT FROM AUTHOR]