The rise of high-performance functional devices has driven significant breakthroughs in various research fields, with ultrafast laser processing offering unprecedented opportunities for advanced device fabrication. This review summarizes recent progress and future prospects for ultrafast laser in fabricating functional optical, semiconductor, and sensor devices. Central to these advances is a deeper understanding of ultrafast laser–matter interaction physics, including nonlinear optical effects, multiphoton ionization, avalanche ionization, and laser-induced plasma dynamics. These phenomena govern carrier excitation, energy deposition, and subsequent structural modification. We further review how such interactions enable controlled refractive index changes, selective ablation, and nanoscale material structuring in photosensitive, dielectric, semiconductor, and metallic substrates. Key applications are then reviewed, including ultrafast laser fabrication of optical devices (e.g., optical waveguide devices, optical data storage elements, optical elements, and artificial compound eyes, integrated photonic devices), semiconductor devices (e.g., semiconductor light-emitting devices, photodiodes, solar cells, and photodetectors), and sensors (e.g., fiber optic sensors, flexible sensors, and biochemical sensors). Recent breakthroughs showcase ultrafast laser-induced precision in device miniaturization, improved optoelectronic characteristics, and integration of complex functions (e.g., topological photonic circuits fabricated via sub-100-nm laser writing, 5D optical data storage in glass with > 1 TB/cm3 density, perovskite solar cells achieving 25.7% efficiency through laser-induced phase engineering, alongside plasmonic biosensors with 100× sensitivity enhancement, and stretchable graphene sensors for wearables). Finally, this review discusses core challenges, such as enhancing the scalability of ultrafast laser processes for industrial-scale production and optimizing laser-material interactions to improve device reliability and performance. Future efforts should address key challenges such as the limited scalability of ultrafast laser processing and the incomplete understanding of laser–matter interactions at ultrafast timescales. Integrating ultrafast lasers with AI-driven control, beam shaping, and advanced materials such as 2D heterostructures may enable smarter and more multifunctional device platforms. A unified theoretical framework is also needed to guide precise and efficient fabrication. These directions highlight critical opportunities for bridging current limitations and enabling transformative advances. While not exhaustive, this review lays a foundation for further research into the transformative potential of ultrafast laser in functional device fabrication.
Radial plasma non-uniformities caused by electrostatic edge and electromagnetic standing wave/skin effects are one of the key factors affecting the process quality and efficiency of large area Capacitively Coupled Plasmas (CCPs) in e.g. etching and deposition processes in semiconductor manufacturing. In this work, multi-electrode CCPs with an additional individually RF driven powered electrode added to the reactor at different locations are studied by 2 d 3 v graphics processing unit accelerated particle-in-cell/Monte Carlo collision simulations to improve uniformity control at low pressures. By including an RF driven electrode at the reactor sidewall, the RF sheath oscillation at the sidewall is found to induce the generation of energetic beam electrons which are accelerated towards the reactor center. Upon reaching the edge of the bottom planar powered electrode, these beam electrons are accelerated upwards towards the top electrode by the bottom electrode sheath, which reduces their radial propagation distance and causes strong localized ionization at the edge of the bottom powered electrode. Under discharge conditions where center high plasma density profiles occur in the absence of such sidewall electrodes this effect enhances the plasma uniformity. Its performance strongly depends on the amplitude and phase of the voltage applied to the sidewall electrode. We also study the effects of segmented planar and individually RF driven ring electrodes on plasma uniformity. Tuning the driving frequency at the outer ring electrode is found to provide better control of the plasma uniformity compared to varying the applied voltage amplitude at the ring electrode. The observed effects are understood based on a detailed analysis of the spatio-temporal electron power absorption dynamics. Overall, including an additional and individually RF driven electrode is found to be an effective method for uniformity control in CCPs. Such multi-electrode CCPs are expected to provide improved flexibility in the control of plasma properties in industrial applications.
A new 3-electrode plasma device powered by a combined nanosecond pulsed (nsp) source and a sub-breakdown pulsed radiofrequency (RF) source at atmospheric pressure in a N2/H2 (97.5%/2.5%) mixture is studied. By applying pulsed excitation sequences from both the nsp and RF sources, two different RF discharge modes are obtained depending on the actual participating electrode pair. In the RF dielectric-barrier-discharge (RF-DBD) mode, the discharge forms between the RF metallic pin electrode and the nsp electrode located behind a dielectric surface (exterior to the reactor). In the RF pin-to-pin (RF-PtP) mode, the RF discharge forms between the RF and grounded metallic pin electrodes, both located inside the reactor. The existence of the two RF discharge modes is highly dependent on the RF pulse duration as revealed using high-speed imaging along with a custom electrical measurement technique. It was observed that for longer duration RF pulses, RF-PtP mode is achieved through a transition of RF-DBD into RF-PtP mode (DBD-PtP transition). Electrical characterization revealed higher coupled power percentages for RF-PtP mode (up to 85%) over RF-DBD mode (25%–75%). However, deteriorating impedance matching of the RF-PtP mode decreased the available RF applied power thus yielding similar plasma power deposition as RF-DBD mode. Plasma characterization performed by analysing the emission of the N2 second positive system provided vibrational temperatures up to 3400 K and a thermalization trend of the rotational temperatures as RF pulse duration increased. Mechanisms behind the DBD-PtP transition are proposed under consideration of the obtained data. We attribute the observed discharge dynamics to diffusional forces acting on charged species such as ambipolar diffusional drift and diffusional charge flow.
Plasma jets are sources of repetitive and stable ionization waves, meant for applications where they interact with surfaces of different characteristics. As such, plasma jets provide an ideal testbed for the study of transient reproducible streamer discharge dynamics, particularly in inhomogeneous gaseous mixtures, and of plasma–surface interactions. This topical review addresses the physics of plasma jets and their interactions with surfaces through a pedagogical approach. The state-of-the-art of numerical models and diagnostic techniques to describe helium jets is presented, along with the benchmarking of different experimental measurements in literature and recent efforts for direct comparisons between simulations and measurements. This exposure is focussed on the most fundamental physical quantities determining discharge dynamics, such as the electric field, the mean electron energy and the electron number density, as well as the charging of targets. The physics of plasma jets is described for jet systems of increasing complexity, showing the effect of the different components (tube, electrodes, gas mixing in the plume, target) of the jet system on discharge dynamics. Focussing on coaxial helium kHz plasma jets powered by rectangular pulses of applied voltage, physical phenomena imposed by different targets on the discharge, such as discharge acceleration, surface spreading, the return stroke and the charge relaxation event, are explained and reviewed. Finally, open questions and perspectives for the physics of plasma jets and interactions with surfaces are outlined.
Atmospheric pressure plasma production of reactive oxygen-nitrogen species (RONS) has demonstrated potential in various biological applications, such as agriculture. Water in close proximity to these plasmas can absorb RONS and then be applied to plants as fertilizer [1], [2]. In order for plasma production of RONS to be industrially viable, it is important to characterize and optimize this process. Two atmospheric pressure plasma devices are investigated, with differing electrical properties, geometries and plasmaliquid dynamics. The devices are electrically characterized to determine discharge current, dissipated power and plasma events. The concentrations of relevant RONS - nitrate, nitrite, hydrogen peroxide and ammonium - absorbed in plasma treated water are measured colorimetrically. Which RONS and in what proportion differs between devices and can be manipulated. The relation between electrical properties - the frequency and number of plasma events - and the production rate of RONS is investigated. Experiments with deionized water have shown direct correlation between the frequency of plasma events and the production rate of RONS. These results will be used to inform the optimization of the plasma devices with the goal of energy efficiency and high RONS production rate to meet the fertilization demands of growing plants.
A diamond-like carbon (DLC) fabrication method with a greater deposition rate and simple equipment configuration facilitates to introduce DLC coating technology to industrial processes. In this study, a gas-injected pulsed plasma CVD method using a single plasma source is proposed as an ultra-high-rate deposition method for DLC films. A gas mixture of Ar and C2H2 was injected into a vacuum chamber through a gas nozzle, and plasma in the chamber was generated by applying a negative pulse voltage to the substrate stage. The gas velocity in the chamber was calculated using computational fluid dynamics simulations. DLC films with a nanoindentation hardness of 17.5 GPa were fabricated on a limited area of a Si substrate at a deposition rate of 2480 nm min−1. The deposition rate of the DLC films can be further improved by optimizing the conditions of the Ar partial pressure ratio, gas velocity, and stage applied voltage.
Plasma sheath studies are of great importance to fusion and propulsion applications involving the flow of plasma through a material channel. Emission of secondary electrons from the material wall is capable of altering the fundamental sheath structure and behavior. At very low energies, the emission spectrum is dominated by the elastic backscattering of particles, while at higher energies cold secondary electrons account for the bulk of the emission. Models for these mechanisms are applied at the boundary of continuum-kinetic plasma sheath simulations for a variety of material parameters. Simulations are performed where emission leads to formation of a space-charge limited sheath, as well as for high-emission cases where the ratio of emitted to impacting particles exceeds unity. Results are presented which examine the relationship between wall materials, emission mechanisms, the plasma regime, and resulting sheath structure.
The Beam Driven Plasma Neutralizer (BDPN) has been proposed as a more efficient alternative to the gas neutralizer for negative-ion based Neutral Beam Injection (NNBI). In this paper we model the performance of an entire NNBI beamline with a BDPN. We simultaneously consider all the relevant physics and engineering aspects, the most important being the plasma density and degree of ionization inside the BDPN as a function of its geometry and feed gas flow, the geometrical transmission of the beamline, the dependence of the neutral gas distribution in the beamline on the geometry of the beamline components and gas flows, and the species evolution of the extracted D$^-$ beam through this neutral and charged particle distribution. Furthermore, we calculate the heat loads expected on the BDPN parts and on the NBI components located downstream of it and study the effect of the magnetic cusp field across the BDPN entrance on beamline transmission. While our results constitute an optimization only under the applied boundary conditions, we find that the beamline with a BDPN increases the system's wall plug efficiency by about 13% to 0.34 from the 0.30 estimated for a gas neutralizer.
A. Listorti, Sara Covella, Alberto Perrotta
et al.
Metal Halide Perovskite (MHP) semiconductors are currently standing out for their exceptional optoelectronic properties and, particularly, for their exploitation in photovoltaics. Their structure can be described by the formula , where A is usually an organic cation, such as methylammonium (MA) or formamidinium (FA), B is a metal cation and X is a halogen anion, typically I or Br. The exceptional properties of MHPs derive by their hybrid organic-inorganic nature, which also allows for low-cost fabrication processing. The raise of perovskite photovoltaics 1 followed progresses on three main research fronts: i) material deposition optimization, ii) material compositional tuning and iii) device interface engineering. The interfaces play a fundamental role in the device function affecting charge extraction, recombination processes and material/device overall stability. Therefore, to further improve the performances of these devices, many surface processes have been applied to solar cells interfaces, most of which include a solution-based methodology 2. The aim of these treatments is not only to improve solar cells efficiency in terms of carrier concentration and transport properties, but also to improve the device stability under working conditions, which is one of the main issues of these materials. Among the different surface treatments exploitable, the use of plasma represents a solvent-free and non-invasive promising strategy to boost MHP solar cells performances. Plasma-deposited coatings on perovskite, as fluorocarbon polymers, have shown to improve material resistance to humidity and photoluminescence properties 3. We have explored the effect of low-pressure plasmas fed with different gases, namely Ar, , and , on Metylammonium Lead Iodide surface4. An interesting improvement of perovskite photoluminescence and solar cell efficiency was observed for Ar and plasma treatments, ascribable both to the removal of organic components, proven to be beneficial to device performances 5, and to other chemical and morphological modifications depending on the gas used. Starting from these results, new plasma surface treatments, plasma-assisted deposition and encapsulation processes will be object of study of future research, to achieve a more complete understanding of the interfacial defects and charge carrier dynamics and to further minimize performance losses and instability issues. References NREL Best Research-Cell Efficiency Chart. https://www.nrel.gov/pv/cell-efficiency.html Han TH, Tan S, Xue J, Meng L, Lee JW, Yang Y. Interface and Defect Engineering for Metal Halide Perovskite Optoelectronic Devices. Advanced Materials. 2019;31(47). doi:10.1002/adma.201803515 Armenise V, Colella S, Milella A, Palumbo F, Fracassi F, Listorti A. Plasma-Deposited Fluorocarbon Coatings on Methylammonium Lead Iodide Perovskite Films. Energies (Basel). 2022;15(13):4512. doi:10.3390/en15134512 Andrea Listorti, Sara Covella, Alberto Perrotta, et al. A study on plasma-assisted modifications of Methylammonium Lead Iodide Perovskite surfaces for photovoltaic applications. Xiao X, Bao C, Fang Y, et al. Argon Plasma Treatment to Tune Perovskite Surface Composition for High Efficiency Solar Cells and Fast Photodetectors. Advanced Materials. 2018;30(9):1-7. doi:10.1002/adma.201705176 Figure 1
Jharna Tamang, Jean De Dieu Nkapkop, Muhammad Fazal Ijaz
et al.
The nonlinear ion-acoustic waves (IAWs) in a space plasma are capable of exhibiting chaotic dynamics which can be applied to cryptography. Dynamical properties of IAWs are examined using the direct method in plasmas composed of positive and negative ions and nonextensive distributed electrons. Applying the wave transformation, the governing equations are deduced into a dynamical system (DS). Supernonlinear and nonlinear periodic IAWs are presented through phase plane analysis. The analytical periodic wave solution for IAW is obtained. Under the influence of an external periodic force, the DS is transformed to a perturbed system. The perturbed DS describes multistability property of IAWs with change of initial conditions. The multistability behavior features coexisting trajectories such as, quasiperiodic, multiperiodic and chaotic trajectories of the perturbed DS. The chaotic feature in the perturbed DS is supported by Lyapunov exponents. This interesting behavior in the windows of chaotic dynamics is exploited to design efficient encryption algorithm. First SHA-512 is used to compute the hash digest of the plain image which is then used to update the initial seed of the chaotic IAWs system. Note that SHA-512 uses one-way function to map input data to the output, consequently it is quite impossible to break the proposed encryption technique. Second DNA coding is used to confuse and diffuse the DNA version of the plain image. The diffused image follows DNA decoding process leading to the cipher image. The security performance is evaluated using some well-known metrics and results indicate that the proposed cryptosystem can resist most of existing cryptanalysis techniques. In addition complexity analysis shows the possibility of practical implementation of the proposed algorithm.
Simulations of Al thin film sputter depositions rely on accurate plasma and surface interaction models. Establishing the latter commonly requires a higher level of abstraction and means to dismiss the fundamental atomic fidelity. Previous works on sputtering processes addressed this issue by establishing machine learning surrogate models, which include a basic surface state (i.e. stoichiometry) as static input. In this work, an evolving surface state and defect structure are introduced to jointly describe sputtering and growth with physics-separating artificial neural networks. The data describing the plasma–surface interactions (PSIs) stem from hybrid reactive molecular dynamics/time-stamped force bias Monte Carlo simulations of Al neutrals and Ar+ ions impinging onto Al(001) surfaces. It is demonstrated that the fundamental processes are comprehensively described by taking the surface state as well as defect structure into account. Hence, a machine learning PSI surrogate model is established that resolves the inherent kinetics with high physical fidelity. The resulting model is not restricted to input from modeling and simulation, but may similarly be applied to experimental input data.
An enhanced electron heating mechanism based on a resonance between the cyclotron motion of electrons and radio frequency (rf) electric field in the plasma bulk is reported in weakly magnetized capacitively coupled argon plasmas at low pressure. When the electron cyclotron frequency coincides with the applied power source frequency, the bulk electrons can continuously acquire energy from the background electric field within certain rf periods during the cyclotron motion, inducing overall distinct increase of excitation rate and electron temperature in the plasma bulk. This enhanced electron heating effect has been examined by a combination of kinetic particle simulations, experimental measurements, and an analytical model, and the dynamics of electrons are revealed at resonant conditions.
Discharge dynamics of primary and secondary streamers in a repetitively pulsed surface dielectric barrier discharge (SDBD) are investigated based on experimental and numerical simulations. Plasma propagation and coupled energy of the primary streamer are restricted in subsequent pulses, but the deposited energy of the secondary streamer increases. When the pulse repetition frequency reduces, a longer plasma length and higher average velocity of the primary streamer can be observed, but the influences on propagation length and velocity of the secondary streamer are very limited. These phenomena indicate that the residual surface charges left by the previous pulse should have a critical effect on the discharge dynamics of subsequent discharges. In order to have a deeper insight into the influence of residual surface charges in a repetitively pulsed SDBD, a numerical model characterized with a pre-charging of homogeneous charge accumulated on the dielectric surface is built. Pre-charging of positive charges deposited on the dielectric surface can inhibit the electric field of applied voltage, resulting in a decrease in the expansion of the primary streamer and the positive peak of current, which is in qualitative agreement with the experimental measurements. However, there is an opposite evolution rule when the negative charges are deposited on the dielectric surface. Although the electric field strength of the secondary streamer is enhanced for a high pre-charging value, there is no great impact on the negative peak of current during the secondary streamer due to the remaining heavy mass ions.
Abstract With the advent of digital industry, intelligent manufacturing is becoming a pillar industry guiding the rapid development of modern industry and daily life of human kind. Nevertheless, the lack of advanced functional materials severely restricts the technological updates and product upgrades. Herein, we developed a facile method to fabricate polyvinylidene fluoride (PVDF)/barium titanate (BaTiO3) spherical piezoelectric powder for SLS processing by combining solid state shear milling (S3M) and plasma technology. With assistance of simulation of heat transfers and molecular dynamics, the transformation of irregular powder to spherical one was successfully clarified by melt surface tension. As a proof-of-concept, the as-prepared spherical powder endowed SLS parts with advanced mechanical properties and piezoelectric properties derived from the excellent accumulation characteristics. The improved piezoelectric properties could reach an open-circuit voltage of 4.7 V and a short-circuit current of 106.5 nA, which exhibited better output performance than those of most reported piezoelectric 3D parts. This work not only contributed a high quality piezoelectric material for SLS processing, but also provided a new route for efficient and clean preparation of polymer-based spherical powder for all chemical engineering fields.
In this article, we consider the problem formulation of dust plasmas with positively charge, cold dust fluid with negatively charge, thermal electrons, ionized electrons, and immovable background neutral particles. We obtain the dust‐ion‐acoustic solitary waves (DIASWs) under nonmagnetized collision dusty plasma. By using the reductive perturbation technique, the nonlinear damped Korteweg‐de Vries (D‐KdV) equation is formulated. We found the solutions for nonlinear D‐KdV equation. The constructed solutions represent as bright solitons, dark solitons, kink wave and antikinks wave solitons, and periodic traveling waves. The physical interpretation of constructed solutions is represented by two‐ and three‐dimensional graphically models to understand the physical aspects of various behavior for DIASWs. These investigation prove that proposed techniques are more helpful, fruitful, powerful, and efficient to study analytically the other nonlinear nonlinear partial differential equations (PDEs) that arise in engineering, plasma physics, mathematical physics, and many other branches of applied sciences.
Nonthermal plasma (NTP) provides a novel approach to developing renewable and efficient nitrogen fixation (NF) technology. However, the efficiency optimization of NTP-assisted NF (NTP-NF) remains challenging due to the elusive ultra-fast plasma process, especially in packed-bed dielectric barrier discharge (PB-DBD). Our work presents a unique view on how to optimize the efficiency of NTP-NF based on precise studies of plasma dynamics and chemistry by developing a novel nanosecond pulse driving PB-DBD model. 2D plasma dynamics show that the plasma propagates in the form of surface ionization waves coupled with filamentary micro-discharge. Electron heating by high instantaneously applied power determines the development of ionization waves and NO production. Plasma chemistry shows that selectively enhancing the energy of electronically excited dissociation to produce N* is the most efficient way to increase the production of NO.