Minimum Voltage Research Articles

PENGARUH ARUS EKSITASI TERHADAP ARUS STATOR MOTOR SINKRON 3 FASA DENGAN VIRTUAL INSTRUMENT

The three-phase current value of a synchronous motor has a great impact on its long-term reliability and performance under load. Therefore, maintenance and monitoring must be performed to determine the performance of synchronous motors. A virtual instrument and its LabView software can be used as a method to determine the operating current value of a synchronous motor. The device used in the study contains a synchronous motor as a load, and his LabView-equipped controller is used to execute commands during synchronous motor testing. NI MyDAQ is used as an input to the controller prior to using LabView, so it can be customized for use as an input to motors and controllers. Power is supplied by adjusting the motor input voltage to 380 volts and the controller input voltage to 220 volts. The purpose of the research is to develop tools and simulation software for synchronous motors that use voltage regulators to react to variations and determine minimum and maximum voltage values to determine motor performance. As a result of examination, the motor output reached a maximum current value of 0.4A at idle and a maximum controller current value.

Maximum Voltage Gain Tracking Algorithm for High-Efficiency of Two-Stage Induction Heating Systems Using Resonant Impedance Estimation

A boost power factor correction (PFC) circuit has replaced the diode rectifier to improve its poor power factor performance, low efficiency, and output power limitation for conventional induction heating (IH) applications. Accordingly, many studies have been conducted, but they considered only the efficiency of the boost PFC rather than the entire IH system, or their control and design were complicated. In this paper, an algorithm tracking the maximum voltage gain of the resonant network is proposed to improve the entire efficiency of the two-stage IH system based on an exact online resonant frequency estimation. It can make the resonant network operate at the maximum voltage gain point which can improve the efficiency of the series-resonant inverter (SRI) included in the IH system with low circulating current, the minimum switching frequency, and zero voltage switching (ZVS) capability. The proposed algorithm also induces the minimum output voltage of the boost PFC, which can reduce its switching losses and total harmonic distortion (THD). The validity of the proposed algorithm is experimentally verified using a 2.4-kW prototype IH system, including the boost PFC and the IH-SRI controlled by a digital signal processor (DSP).

FinFET 6T-SRAM All-Digital Compute-in-Memory for Artificial Intelligence Applications: An Overview and Analysis.

Artificial intelligence (AI) has revolutionized present-day life through automation and independent decision-making capabilities. For AI hardware implementations, the 6T-SRAM cell is a suitable candidate due to its performance edge over its counterparts. However, modern AI hardware such as neural networks (NNs) access off-chip data quite often, degrading the overall system performance. Compute-in-memory (CIM) reduces off-chip data access transactions. One CIM approach is based on the mixed-signal domain, but it suffers from limited bit precision and signal margin issues. An alternate emerging approach uses the all-digital signal domain that provides better signal margins and bit precision; however, it will be at the expense of hardware overhead. We have analyzed digital signal domain CIM silicon-verified 6T-SRAM CIM solutions, after classifying them as SRAM-based accelerators, i.e., near-memory computing (NMC), and custom SRAM-based CIM, i.e., in-memory-computing (IMC). We have focused on multiply and accumulate (MAC) as the most frequent operation in convolution neural networks (CNNs) and compared state-of-the-art implementations. Neural networks with low weight precision, i.e., <12b, show lower accuracy but higher power efficiency. An input precision of 8b achieves implementation requirements. The maximum performance reported is 7.49 TOPS at 330 MHz, while custom SRAM-based performance has shown a maximum of 5.6 GOPS at 100 MHz. The second part of this article analyzes the FinFET 6T-SRAM as one of the critical components in determining overall performance of an AI computing system. We have investigated the FinFET 6T-SRAM cell performance and limitations as dictated by the FinFET technology-specific parameters, such as sizing, threshold voltage (Vth), supply voltage (VDD), and process and environmental variations. The HD FinFET 6T-SRAM cell shows 32% lower read access time and 1.09 times better leakage power as compared with the HC cell configuration. The minimum achievable supply voltage is 600 mV without utilization of any read- or write-assist scheme for all cell configurations, while temperature variations show noise margin deviation of up to 22% of the nominal values.

Ternary Heterostructures Based on BaTiO3/MoO3/Ag for Highly Efficient and Reusable Photocatalytic Applications

AbstractThis work shows the fabrication of an efficient ternary heterostructure photocatalyst by integrating ferroelectric BaTiO3 (BTO) as the bottom layer, semiconductor MoO3 as the middle layer and plasmonic silver nanoparticles (Ag NPs) as the top layer, respectively. The BaTiO3/MoO3/Ag (BMA) heterostructure exhibits a higher photodegradation and photocatalytic efficiency of 100% for rhodamine B (RhB) dye under a UV–Visible light illumination of 60 min when compared with its binary heterostructure counterparts BaTiO3/Ag (BA) and MoO3/Ag (MA). The increased photocatalytic activity in BMA heterostructure is attributed to its enhanced interfacial electric field due to the electric double layer formation at BTO‐MoO3 and MoO3‐Ag interfaces. The higher blueshift in the surface plasmon resonance (SPR) peak observed for the BMA heterostructure clearly indicates an increased electron transfer toward the top Ag NPs layer under optical illumination. The higher resistive switching (RS) ratio, the increased difference in voltage minima, and the improved photocurrent generation, as evident from the I–V characteristics, illustrate the enhanced charge carrier generation and separation in BMA heterostructure. A smaller arc radius observed for the Nyquist plot of BMA heterostructure clearly showcases its increased interfacial charge transfer (CT). The CT mechanism and reusability of the BMA heterostructure are also studied.

Highly efficient ternary NiO/MoS2/BiVO4 heterostructure for electrocatalytic HER/OER applications

The field of ternary-based electrocatalyst design and fabrication has attracted considerable attention due to the unique physio-chemical and heterostructural properties exhibited by electrode materials in the realm of fuel generation. In this study, we present a straightforward method for efficiently constructing an electrocatalyst capable of facilitating the electrocatalytic splitting of H2O. Our approach involves the assembly of NiO nanoparticles onto MoS2 and BiVO4 using ultrasonication. Spectroscopic analysis reveals the presence of moderated electronic configurations resulting from a robust chemical interaction within the nanostructure. This interaction induces a charge shift from Ni2+ to Mo6+/Mo4+ across the interfacial Mo–S–Ni bond, leading to an increase in active sites and facilitating charge/mass transfers for the OER and HER within the nanostructures. Furthermore, the NiO/MoS2/BiVO4 nanostructure exhibits exceptional catalytic performance under alkaline conditions. It demonstrates a low overpotential of 300 mV for the OER and 95 mV at 10 mA cm−2 for the HER. Importantly, the nanostructured electrode maintains remarkable electrochemical stability for both HER and OER, as evidenced by minimal voltage fluctuations even after continuous operation for 24 h. This work highlights a simple yet significant strategy for optimizing electronic configurations using dual-functional transition metal-based electrocatalysts in the context of H2O splitting.

Rechargeable Solid-State Na-Metal Battery Operating at -20 °C.

Achieving satisfactory performance for a solid-state Na-metal battery (SSNMB) with an inorganic solid electrolyte (SE), especially under freezing temperatures, poses a challenge for stabilizing a Na-metal anode. Herein, this challenge is addressed by utilizing a Natrium super ionic conductor (NASICON) NASICON-type solid electrolyte, enabling the operation of a rechargeable SSNMB over a wide temperature range from -20 to 45 °C. The interfacial resistance at the Na metal/SE interface is only 0.4 Ω cm2 at 45 °C and remains below 110 Ω cm2 even at -20 °C. Remarkably, long-term Na-metal plating/stripping cycles lasting over 2000h at -20 °C are achieved with minimal polarization voltages at 0.1mA cm-2 . Further analysis reveals the formation of a uniform Na3- x Cax PO4 interphase layer at the interface, which significantly contributes to the exceptional interfacial performance observed. By employing a Na3 V1.5 Al0.5 (PO4 )3 cathode, the full battery system demonstrates excellent adaptability to low temperatures, exhibiting a capacity of 80mA h g-1 at -20 °C over 50 cycles and retaining a capacity of 108 mAh g-1 (88.5% of the capacity at 45 °C) at 0 °C over 275 cycles. This research significantly reduces the temperature threshold for SSNMB operation and paves the way toward solid-state batteries suitable for all-season applications.

Development of bespoke hardware and software to enable testing of a novel method of managing the charge and discharge of series-connected battery packs

The novel feature of the method of battery management under development and testing is that routine balancing of the cells is eliminated throughout the service life of the battery pack. This requires preparation of the battery cells and configuration of the rigs in such a way as to ensure that the cells are accurately balanced on assembly and that thereafter there is no cell-to-cell variation in charge current or load at any time, measured to a low microamp level. In addition, the method requires a special charge control algorithm which was devised in order to accommodate cell-to-cell variations in capacity and dynamic response.Comprehensive experimental testing of this method, which is fully described in the associated paper (Hardy et al., 2023), required the development of hardware and software which would combine the necessary functions of a battery test rig and a battery management system capable of carrying out the special method of charge control described below. These included:•The automated control of contactors, loads and chargers to perform multiple charge/discharge cycles to predetermined patterns of current and maximum and minimum cell voltages.•Monitoring of cell voltages, current and temperature and the provision of test and diagnostic data.•Performing the safety functions of a Battery Management System to ensure that no cell was permitted to exceed limitations of current, voltage or temperature.The hardware and software were developed through three phases of testing with the operational principles (but not all the hardware and software elements) carrying over from one phase to the next.

Dynamically controllable current reference technique for current-feedback low dropout regulator

This paper proposes the dynamically controllable current reference (DCCR) technique for a wide input range, transient enhancement current-feedback low dropout regulator (WTELDO) to achieve transient enhancement. Combined with a transient enhanced current mirror (TE-CM) adopting an enhanced active resistance network, this technique which is designed based on dynamic bias improves the slewing rate of the power transistor gate but also increases the loop bandwidth. Finally, this WTELDO can reduce the minimum input voltage due to the current-feedback technique and improve the transient response under the condition of maintaining low quiescent current. This designed WTELDO was fabricated in SMIC 0.18μm CMOS process. The input voltage range is 0.8–2.2 V. The output voltage is 0.64 V. The maximum load current is 50 mA and the static current consumption is about 26 μA. Its maximum current efficiency is up to 99.948%. The test results show that the overshoot is 117.5 mV and the undershoot is 167.5 mV when the load current is switched between 0 mA and 50 mA within 300 ns under a 100 pF load capacitor.

Digital Twin-Based Remaining Driving Range Prediction for Connected Electric Vehicles

&lt;div&gt;Electric vehicles (EVs) suffer from long charging time and inconvenient charging due to limited charging stations, which are the main causes of drivers’ range anxiety. Real-time and accurate driving range prediction can help drivers plan journeys, alleviate range anxiety, and promote EV development. However, predicting the EV driving range is challenging due to different weather, road conditions, driver habits, and limited available data. To address this issue, this article proposes a novel digital twin-based driving range prediction method. First, a one-year real-world EV dataset in Beijing is utilized. Detailed feature selection is conducted for the dataset, and six key features are extracted: battery SOC, consumed battery SOC, battery total voltage, battery maximum cell voltage, battery minimum cell voltage, and mileage already driven. Then, a random forest method is used to train the EV driving range prediction model using the features described earlier. Four prediction models with different adopted features are trained, respectively. Finally, the sliding window algorithm is proposed for the input of random forest to investigate its impact on prediction accuracy in the four prediction models, and different window sizes are evaluated. Results show that the sliding window algorithm can significantly improve the prediction model with only SOC as input, while it can deteriorate other models with more features. The most accurate model taking all six features as inputs provides 89.8% data that has an accuracy of over 80%, while data proportion of the prediction model without past energy consumption is only 31.8%.&lt;/div&gt;

Voltage, thermal and magnetic field fiber sensors based on magnetic nanoparticles-doped photonic liquid crystal fibers.

In this article, highly sensitive voltage, thermal and magnetic field fiber sensors were obtained in magnetic nanoparticles-doped E7 liquid crystals filled into photonic crystal fibers (PLCF). The voltage and temperature sensitivity reached at 12.598 nm/V and -3.874 nm/°C, respectively. The minimum voltage response time is 48.2 ms. The phase transition temperature Tc of liquid crystal with magnetic dopant was reduced from 60 °C to 46 °C. The magnetic field sensor based on magnetic nanoparticles-doped PLCF were obtained with sensitivity of 118.2 pm/mT from 400 to 460 mT.

Robust optimization model of flexible distribution network considering source-load uncertainty

The increase in renewable energy permeability and the electrical load uncertainty aggravates the fluctuation of power flow and bus voltage magnitudes of the distribution network (DN). Then, the fluctuation threatens system security and makes increasing difficulties in DN regulation. However, the widespread utilities of power electronic technology promote rapid developments in flexible distribution networks, thereby providing certain opportunities to treat the open question. Therefore, this study proposes a robust optimization model of flexible distribution network allowing for system security and economy. Firstly, a optimal power flow (OPF) model of flexible distribution network with various active management strategies is derived and constructed by taking the minimum loss and voltage offset as the objective function. The model is linearized and relaxed to convex problem by a second-order cone. Then, the robust OPF model of flexible distribution network is established considering the uncertainty of load and renewable energy. Finally, a relaxation-based co-evolution algorithm is proposed to solve the model. The modified IEEE 33 bus system and PG&E 69 bus system are involved for case studies, in which the calculation results under various scenarios are compared. Consequently, the effectiveness and practicability of proposed model to locate and cope with the worst situation is demonstrated.

Voltage Zoning Regulation Method of Distribution Network with High Proportion of Photovoltaic Considering Energy Storage Configuration

Photovoltaics have uncertain characteristics. If a high proportion of photovoltaics are connected to the distribution network, the voltage will exceed the limit. In order to solve this problem, a voltage regulation method of a distribution network considering energy storage partition configuration is proposed. Taking the minimum total voltage deviation, the minimum total cost, the minimum total power loss, and the minimum energy storage device installation ratio as the objective function, and considering various conditions, such as voltage deviation constraint and energy storage constraint, a mathematical model of voltage regulation is established. Firstly, a high proportion of photovoltaics are connected to the distribution network, and the voltage deviation curve is obtained. The optimal k value is determined by the elbow rule. The voltage deviation curve of each node is clustered by the k-means algorithm so as to determine the energy storage device partition. The energy storage device is connected to various clustering centers, and then the weighting factor of each objective function is determined by the fuzzy comprehensive evaluation method. For comparison and analysis, (k + 1) schemes are determined through the partition configuration of (k + 1) energy storage devices. Then, the model is solved by particle swarm optimization, and the unit output result and the minimum objective function value are obtained. Finally, an example of IEEE33 is used to verify the effectiveness of the proposed model.

Design and analysis of high-gain DC–DC chopper topologies for PV-fed BLDC motor drive system

PurposeSwitching power converters for photovoltaic (PV) applications with high gain are rapidly expanding. To obtain better voltage gain, low switch stress, low ripple and cost-effective converters, researchers are developing several topologies.Design/methodology/approachIt was decided to use the particle swarm optimization approach for this system in order to compute the precise PI controller gain parameters under steady state and dynamic changing circumstances. A high-gain q- ZS boost converter is used as an intermittent converter between a PV and brushless direct current (BLDC) motor to attain maximum power point tracking, which also reduces the torque ripples. A MATLAB/Simulink environment has been used to build and test the positive output quadratic boost high gain converters (PQBHGC)-1, PQBHGC-8, PQBHGC-4 and PQBHGC-3 topologies to analyse their effectiveness in PV-driven BLDC motor applications. The simulation results show that the PQBHGC-3 topology is effective in comparison with other HG cell DC–DC converters in terms of efficiency, reduced ripples, etc. which is most suitable for PV-driven BLDC applications.FindingsThe simulation results have showed that the PQBHGC-3 gives better performance with minimum voltage ripple of 2V and current ripple of 0.4A which eventually reduces the ripples in the torque in a BLDC motor. Also, the efficiency for the suggested PQBHGC-3 for PV-based BLDC applications is the best with 99%.Originality/valueThis study is the first of its kind comparing the different topologies of PQBHGC-1, PQBHGC-8, PQBHGC-4 and PQBHGC-3 topologies to analyse their effectiveness in PV-driven BLDC motor applications. This study suggests that the PQBHGC-3 topology is most suitable in PV-driven BLDC applications.

Optimization Method of Energy Storage Configuration for Distribution Network with High Proportion of Photovoltaic Based on Source–Load Imbalance

After a high proportion of photovoltaic is connected to the distribution network, it will bring some problems, such as an unbalanced source and load and voltage exceeding the limit. In order to solve them, this paper proposes an optimization method of energy storage configuration for a high-proportion photovoltaic distribution network considering source–load imbalance clustering. Taking the minimum total voltage deviation, the minimum total power loss and the minimum total operating cost as the objective function, and considering various constraints such as power balance constraints and energy storage operation constraints, a mathematical model for energy storage configuration optimization is established. Firstly, the source–load imbalance of the distribution network with a high proportion of photovoltaic is defined. Therefore, according to the 24 h photovoltaic and load data, the 24 h source–load imbalance can be obtained, and the optimal k value can be determined by the elbow rule, so that 24 h a day can be clustered into k periods by the k-means algorithm. Then, the fuzzy comprehensive evaluation method is used to determine the weight factors of each objective function in each period, and three scenes are determined according to the different amount of energy storage. Then, the hybrid particle swarm optimization algorithm proposed in this paper is used to solve the model, and the minimum objective function value, optimal position and optimal capacity of each energy storage grid in each scene are obtained. Finally, it is applied to an example of IEEE33. In the results, the total voltage deviation is increased by more than 10%, the total power loss is increased by more than 8% and the total operating cost is increased by more than 12%, which verifies the effectiveness of the proposed model.

Analytical modeling of negative capacitance transistor based ultra low power Schmitt trigger

Through an analytical framework, the work showcases the potential benefits of Metal-Ferroelectric-Metal-Insulator-Semiconductor (MFMIS) negative capacitance (NC) transistor (T) to enhance the hysteresis width (ΔVH) and reduce the minimum supply voltage (Vdd,min) of ultra low power (ULP) subthreshold Schmitt trigger (ST) at shorter gate lengths. Analyzing different ST configurations i.e. 2T (both NCFET), 4T-hybrid (realized through combination of NCFETs and MOSFETs), and 6T (all NCFETs or MOSFETs), leads to the inferences that (i) an inherent negative differential resistance of NCFET can be utilized for hysteresis in 2T-ST circuit, (ii) 4T-hybrid ST is not beneficial for enhancing ΔVH due to a current mismatch between MOSFET and NCFET, and (iii) an optimized 2T-ST and 6T-ST designed with high-permittivity (κ) sidewall spacer (Si3N4) and ferroelectric layer (6 nm) can function at Vdd,min of ∼ 55 mV, and ∼ 39 mV, respectively. Results indicate towards potential benefits of realizing ULP subthreshold ST through MFMIS NCFETs without any circuit overhead.

An Ultra-Low-Voltage 2.4-GHz Flicker-Noise-Free RF Receiver Front End Based on Switched-Capacitor Hybrid TIA With 4.5-dB NF and 11.5-dBm OIP3

In this article, an ultra-low-voltage 2.4-GHz radio frequency (RF) receiver front-end architecture targeting the removal of output flicker noise is presented, making it possible to use zero-IF topology for narrow-band communication standards. The trans-impedance amplifier (TIA) is built on the proposed hybrid operational trans-conductance amplifier (OTA) with a switched-capacitor (SC) amplifier as the first gain stage and an active primary–secondary amplifier as the second gain stage, achieving an imperceptible flicker-noise corner frequency. With the SC gain stage, the interstage common-mode voltage can be set to 0 V, which reduces the minimum supply voltage to 0.5 V. As another benefit, dc offset compensation (DCOC) is performed inherently in the interstage sampling and coupling process. Fabricated in 28-nm RF CMOS process, the front-end prototype, including an on-chip matching inductor, occupies a die area of 0.8 mm <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$^{2}$</tex-math> </inline-formula> . Operating in the Industrial Scientific Medical (ISM) frequency band of 2.4 GHz with 1-MHz IF bandwidth, the front end provides a 36–40-dB conversion gain, an 11.5-dBm OIP3, and a flicker-noise corner frequency less than 10 kHz with the supply voltage ranging from 0.5 to 0.6 V. The RF impedance matching network provides passive voltage gain before the low-noise trans-conductance amplifier (LNTA), achieving a 4.5-dB noise figure (NF) with 0.8-mA biasing current in the <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$g_m$</tex-math> </inline-formula> stage. With the ultra-low supply voltage and the passive IF gain stage, the power consumption of the proposed front end is only 610 <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\mu $</tex-math> </inline-formula> W under a 0.53-V supply voltage.

ИСПОЛЬЗОВАНИЕ ПОЛУПРОВОДНИКОВЫХ ЭЛЕМЕНТОВ ПЕЛЬТЬЕ В ГАЗОИСПОЛЬЗУЮЩЕМ ВАРОЧНОМ КОТЛЕ

Cooking boilers powered by natural gas are promising equipment for the preparation of feed in private farms. Based on the patent search, it has been established that there is a wide choice of gas-using boilers with different levels of automation of the process of thermal processing of the product and ensuring safety during operation. At the preliminary stage of the study, it was found that with a smooth control of the power of the gas burner of the digester during the preparation of feed, gas savings of up to 19% are achieved. The principle of self-regulation of gas consumption by a gas burner is determined in proportion to the heat flow consumed by the digester. A working experimental sample was made on the basis of an automation kit for a digester with smooth control of the power of a gas burner. A mathematical model has been developed that describes the processes of heat and mass transfer in a feed boiler with self-regulation of power. Based on the analysis of energy supply systems in digesters and heating boilers, the expediency of developing a new promising power self-regulation scheme based on Peltier semiconductor thermoelements has been established. As shown by the results of experimental studies of automation in various operating modes, the voltage on thermoelectric elements changes in proportion to the temperature difference. It is established that the minimum voltage is 0.07V, the maximum is 0.7V. The voltage and temperature of the product and hot steam in the jacket were measured using TEK DT 830B multimeters. It has been established that the best sensitivity of the thermal regime control system is achieved if the thermoelectric converter module is equipped with nine elements that change the output voltage in proportion to the temperature difference in the steam jacket of the digester.

Insufficient desorption of ions in constant-current membrane capacitive deionization (MCDI): Problems and solutions

Membrane capacitive deionization (MCDI) is a water desalination technology that involves the removal of charged ions from water under an electric field. While constant-current MCDI coupled with stopped-flow during ion discharge is expected to exhibit high water recovery and good performance stability, previous studies have typically been undertaken using NaCl solutions only with limited investigation of MCDI performance using multi-electrolyte solutions. In the present work, the desalination performance of MCDI was evaluated using feed solutions with different levels of hardness. The increase of hardness resulted in the degradation of desalination performance with the desalination time (Δtd), total removed charge, water recovery (WR) and productivity decreasing by 20.5%, 21.8%, 3.8% and 3.2%, respectively. A more serious degradation of WR and productivity would be caused if Δtd decreases further. Analysis of the voltage profiles and effluent ion concentrations reveal that the insufficient desorption of divalent ions at constant-current discharge to 0 V was the principal reason for the degradation of performance. The Δtd and WR can be improved by discharging the cell using a lower current but the productivity decreased by 15.7% on decreasing the discharging current from 161 to 107 mA. Discharging the cell to a negative potential was shown to be a better option with the Δtd, total removed charge, WR and productivity increasing by 27.4%, 23.9%, 3.6% and 5.3%, respectively, when the cell was discharged to a minimum voltage of – 0.3 V. Use of such a method should be feasible for operation of full scale MCDI plants and would be expected to lead to better regeneration of the electrode, improved desalination performance and, potentially, a significant reduction in the need for use of clean-in-place procedures.

An eco-friendly BaTiO3/gelatin composite for flexible and reusable piezoelectric nanogenerators

The degradability and recycling of piezoelectric devices are of great practical importance. In this letter, we present a novel reusable device consisting of piezoelectric BaTiO3 nanoparticles embedded in a degradable gelatin matrix. The device exhibits exceptional flexibility, a high output voltage of 3 V, and a maximum power density of 0.06 μW/cm2. Furthermore, the reconstruction experiment demonstrates the device’s remarkable stability and reliability, as evidenced by its minimal output voltage attenuation.

Selectively Nitrogen Doped ALD-IGZO TFTs with Extremely High Mobility and Reliability.

Achieving high mobility and reliability in atomic layer deposition (ALD)-based IGZO thin-film transistors (TFTs) with an amorphous phase is vital for practical applications in relevant fields. Here, we suggest a method to effectively increase stability while maintaining high mobility by employing the selective application of nitrous oxide plasma reactant during plasma-enhanced ALD (PEALD) at 200 °C process temperature. The nitrogen-doping mechanism is highly dependent on the intrinsic carbon impurities or nature of each cation, as demonstrated by a combination of theoretical and experimental research. The Ga2O3 subgap states are especially dependent on plasma reactants. Based on these insights, we can obtain high-performance indium-rich PEALD-IGZO TFTs (threshold voltage: -0.47 V; field-effect mobility: 106.5 cm2/(V s); subthreshold swing: 113.5 mV/decade; hysteresis: 0.05 V). In addition, the device shows minimal threshold voltage shifts of +0.45 and -0.10 V under harsh positive/negative bias temperature stress environments (field stress: ±2 MV/cm; temperature stress: 95 °C) after 10000 s.