Microsystem Technologies最新文献

The worldwide electrical market’s restructuring over the past few decades has made network congestion inescapable. Congestion in the power system network jeopardizes the power industry’s security, reliability, and economics. Congestion management has thus become one of the most important tasks for system operators in deregulated power markets. Using the hybrid water cycle moth flame optimization (WCMFO) algorithm, this research proposes a method for controlling transmission line congestion in the deregulated power system. This research explores generator rescheduling-based congestion control in the centralized power market model. Newton–Raphson load flow is used to keep all the network constraints within their upper and lower bounds. Congestion cost minimization is the main goal of the proposed congestion management (CM) problem; however, when there is no congestion in the system, the goal shifts to minimization of the total expense of generation, and this instance is taken into consideration as a point of reference when resolving the issue in congested states. For various scenarios of congestion driven by a transmission line failure along with an increase in load in the conventional IEEE 30 bus test system, the congestion-control issue is resolved using the WCMFO algorithm in Matlab software. Simulation tests and data analysis demonstrate that the suggested approach is capable of determining the minimal congestion cost by successfully removing system congestion.

The motion nonlinearity of gimbaled micromirror is studied using the motion equations for the application to omnidirectional scanning of light detection and ranging. The numerical calculations show that the nonlinearity by the motion interaction between mirror and gimbals is dependent intricately on the moments of inertia along respective axes as well as angular velocities and damping factors. The nonlinear terms of the equations increase with the increase of the difference of the moments of inertia along the two orthogonal axes of mirror. The motion nonlinearity relatively decreases with the increase of the dumping coefficient. A gimbaled micromirror with the electrostatic comb actuators was fabricated from a silicon-on-insulator wafer and the motion was observed around the resonant frequency of 5.3 kHz. The expected circular trajectory was deformed to be elliptical. The trajectory was stable but occasionally became uncontrollable by the voltage and the frequency of the actuators. The minimization of the motion nonlinearity is discussed from the viewpoints of inertia and damping.

Piezoelectric pumps play a crucial role in microfluidics owing to their compact size, minimal noise, and absence of electromagnetic interference, rendering them exceptionally versatile. As technology advances, the field of microfluidics requires higher standards for miniaturization, flow rate, and pressure of piezoelectric pumps. This paper introduces two novel miniature valve-based piezoelectric liquid pump with distinct structures: the Mono-port valved piezoelectric micropump (MPVPM) and the Bi-port valved piezoelectric micropump (BPVPM). The primary distinguishing factor between the two is the number of cantilever beam valves at the outlet, with the former featuring one set and the latter featuring two sets. Firstly, simulation software is employed to analyze the inlet/outlet valves, the surrounding flow field, microchannels, and the overall operation process. Secondly, the key structural parameters of the piezoelectric pump are optimized through experiments. Finally, prototypes of both piezoelectric pumps are fabricated, and their output performance indicators are tested and compared. According to simulation and experimental results, the BPVPM demonstrates a faster discharge rate of fluid from the chamber compared to the MPVPM. The arc-shaped channel in the BPVPM exhibits superior energy transfer efficiency. It has been observed that both the flow rate and pressure of the piezoelectric pump initially increase with driving frequency, followed by a decrease, while they increase linearly with voltage. Under optimal operating conditions, the MPVPM achieves a flow rate of 4.4 mL/min and a pressure of 21 kPa, whereas the BPVPM achieves 5.1 mL/min and 25.7 kPa. This suggests that BPVPM has a superior output performance compared to MPVPM. Additionally, both proposed piezoelectric pumps have the same dimensions of 7 mm x 7 mm x 1.5 mm, making them compact and efficient. This piezoelectric pump exhibits good comprehensive output performance in a small size and holds potential practical value in fields such as biomedical, cooling systems, fuel supply, and chemical engineering.

This research article proposes a III-nitride Nano-HEMT designed on improved lattice-matched substrate material of β-Ga₂O₃. The Silvaco Atlas tool is utilized to investigate the linearity characteristics of proposed AlGaN/GaN/β-Ga₂O₃ HEMT design for emerging RF/Microwave applications. The proposed device is equipped with an Al_0.12Ga_0.88N back-barrier design that strengthens the charge carrier concentration at GaN/AlGaN heterojunction by raising its conduction band discontinuity. The drop in Al concentration in back-barrier prompted to entire relaxation of lattice. It also efficiently reduces the substrate leakage current, improves RF/Microwave parameters, and bends the conduction band upwardly convex; all of these contribute an improvement in two-dimensional electron gas (2DEG) confinement. Furthermore, field plate arrangement modifies the electric field, adds more feedback capacitance from drain to gate terminal, and triggers a hole current to be suppressed, and the hole depletion area to enlarge. The investigation conducted through simulations demonstrated that the adoption of AlGaN as a back barrier contributed to a noteworthy decrease in leakage current, a positive shift in threshold voltage (-0.18 V), an improved peak transconductance (624 mS/mm), a transconductance generation factor of 8.8 V^− 1, and better intrinsic gain (A_v) and early voltage (V_EA). These excellent findings demonstrate the viability of the proposed Nano-HEMT design for RF/Microwave applications.

In this work, a Dielectrically Modulated Junctionless Rectangular Gate All Around Field Effect Transistor (DM-JLRGAA-FET) is demonstrated and explored for label free detection of neutral biomolecules. In comparison to its conventional architectures, proposed biosensor exhibits a significantly improved sensing and conjugation performance due to its remarkable structure, which enhances its performance by providing substantial rejection to SCEs (short channel effects) and strengthened gate control over channel electrostatics. Drain current sensitivity, surface potential, transconductance and output conductance are employed to determine the sensing competence of the proposed biosensor. The proposed biosensor offers maximum drain current sensitivity of 8.09 for keratin biomolecule. The detection will become quite difficult during conjugation of two or more biomolecules. The conjugation analysis is also investigated by effective dielectric constant approach governed by Bruggeman’s Model. The conjugations of Streptavidin-Keratin and Streptavidin-Zein is studied for various concentration in the cavity. Conjugations of Streptavidin and Keratin shows the highest sensitivity of 18.5%. The sensing performance of proposed biosensor is optimized for schottky source/drain contacts engineering and also for channel material engineering.

This paper presents biomolecule identification process using a novel biosensing technique with high-K metal–oxide–semiconductor high electron mobility transistor (MOSHEMT). The authors have simulated a MOSHEMT device with high-K dielectric material to improve the sensitivity of biosensors. High-K dielectric material is utilized to examine the electrical efficacy of MOSHEMT-based biosensors. When high-K materials are used, two-dimensional electron gas (2DEG) benefits from carrier confinement and leakage current reduction. Therefore, the on-current of the device has been increased. For numerical modeling, TCAD Silvaco Atlas is used. For label-free identification of biomolecules, simulator is used to investigate and compare various performance parameters with SiO₂ MOSHEMT. Experimental evidence verifies the accuracy of the model. According to the authors' knowledge, this is the first investigation on high-K dielectric AlGaN/GaN MOSHEMT biosensors for efficient label-free biomolecule detection. AlGaN/GaN MOSHEMTs, which use a high-K material, are found to be promising for use in biosensors.

The study of a micro-electro-mechanical-system (MEMS) based capacitive micromachined ultrasonic transducer (CMUT) is considered. The characteristics and behavioral studies of circular, hexagonal and square designed membranes are achieved. The circular CMUT provided better performance regarding membrane displacement, frequency and capacitance profiles. The study also includes the stress and strain behaviors of the membranes. The stress and strain profiles show circular CMUT has the highest tensile strength as compared to the other models. On the contrary substrate area is wasted for circular membranes in the context of array formation. The performances of the three CMUTs are analytically studied and simulations are done using COMSOL Multiphysics. The geometry is validated using this software by establishing frequency at which maximum displacement occurs. The key contribution of this work is to study the different shaped CMUT cells in order to corporate in array formation for further analysis.

In this work, the authors have investigated and proposed an analytical model for different mole fraction variation for the Al_xGa_1−xN/AlN/GaN MOSHEMT. The mole fraction ‘x’ represents the percentage of Al content in Al_xGa_1−xN. The increase in mole fraction enhances the device performance by increasing band bending and 2-dimensional electron gas (2DEG) charge. The drain current, 2DEG charge, threshold voltage, capacitance, cutoff frequency are analyzed for variation of mole fraction. The model has been validated through comparisons with experimental data and the simulation results from Sentaurus TCAD (Technology Computer-Aided Design). The Al_xGa_1−xN barrier layer with 0.17, 0.2, 0.25 and 0.3 of Al mole fractions are analyzed. The Al_xGa_1−xN/AlN/GaN MOSHEMT produces a high drain current of 772 mA/mm for Al mole fraction of x = 0.3 and transconductance of 288 mS/mm for V_gs of 3 V. The cutoff frequency of 52 GHz achieved with 0.3 mol fraction. The higher the mole fraction of Al gives better the Analog/RF performance which can be used in high power RF/Microwave applications.

In order to guarantee grid stability and efficiently manage energy resources, there has been a substantial energy transition brought about by growing worries about resource depletion, climate change, and environmental pollution. Energy is the basic requirement for the sustainable development of human society. Conventional energy resources are limited and causing environmental disturbances consistently. Renewable energy offers better alternatives to tackle current energy crisis. A significant proportion of power generated in India is now coming from solar PV systems. However, due to its intermittence nature, efficient MPPT algorithm becomes necessity to extract maximum output power from the system to enhance its efficiency. Therefore, we have proposed a novel neural network based MPPT algorithm and presents a comparative analysis with conventional MPPT techniques ‘Perturb and Observe’, and ‘Incremental Conductance’ based techniques. The experimental outcomes are validated which shows neural network based MPPT algorithm provides better performance characteristics like reduced steady state error compared to conventional techniques. The parameters considered for comparison are rise time, settling time and power output under different environmental conditions such as irradiance and temperature. Finally, the proposed MPPT controller’s performance is evaluated in MATLAB environment and simulation results show the proposed scheme’s superiority as compared to conventional control techniques under different operating conditions.

The last decade has witnessed a notable surge in the use of multilevel inverters, attributed to their ability to produce waveforms with enhanced harmonic profiles. These inverters have found wide application in high-voltage and high-power scenarios. Multilevel inverters offer advantages such as lower total harmonic distortion (THD), reduced voltage stress on switching devices, minimized switching losses, and smaller passive filter sizes. They serve in various applications, including AC drives, FACTS, and distributed generation. This study presents a comprehensive performance assessment of solar energy-driven cascaded H-bridge multilevel inverters (CHB-MLIs). This paper analyses the performance of 5-level and 7-level cascaded multilevel inverters using the Equal Phase (EP) method across different load conditions. The investigation involves MATLAB/Simulink software simulation studies and experimental validation on a prototype setup. The results demonstrate the effectiveness and feasibility of employing solar energy-driven cascaded H-bridge multilevel inverters for power conversion applications. This research contributes to understanding the performance characteristics of such inverters in solar energy systems, providing valuable insights for their practical implementation and integration into renewable energy grids. The study calculates the harmonics of cascaded multilevel inverters by substituting solar input for batteries. Results indicate that THD decreases as the inverter level increases while efficiency improves.