E. J. Devid, W. Bongers, P. Groen, M. van Ginkel, S. Doyle, F. M. A. Smits, C. F. A. M. van Deursen, K. Serras, S. Labeur, M. A. Gleeson, M. C. M. van de Sanden
Electrodeless Low-Frequency (LF)/Radio-Frequency (RF) plasma sources often suffer from low power coupling efficiencies due to the lack of overlapping field with the dynamic plasma load. However, the power supplies for these plasma sources typically have very high power efficiencies (>90%) and are more cost-effective compared to microwave sources. If the coupling efficiency to the plasma can be increased, these plasma sources offer a competitive technology for the sustainable electrification of the chemical industry. This work experimentally investigates five power coupling methods, applied to toroidal CO2 plasmas in a quartz vessel. The research was based on similar ferrite coupling as used in energy-efficient plasma lamps. The higher resistance of the CO2 plasma decreased the power coupling from 90% (for mercury-vapor plasma) to 66% at 1 mbar. High coupling efficiencies in LF/RF powered discharges can be achieved in two manners: either the inductance of the transformer cores can be increased, or the electromagnetic wave frequency can be increased. Furthermore, additional ferrite cores in parallel with the primary coils can be used to increase the impedance transformation. An experiment with six ferrite cores with a single primary winding in parallel, at a frequency of about 10 MHz and a power of 1 kW, showed that this frequency has a detrimental effect on the magnetic permeability and the losses in the ferrite result in a decrease of coupling to 33% at 1.5 mbar. At a frequency of 66 kHz with a nanocrystalline soft magnetic material core, a coupling of 89% was achieved in 1.5 mbar plasma for a power of 3.1 kW. This configuration exhibits decreasing coupling efficiencies at higher pressures since the plasma impedance increases, which again limits the coupling of the transformer due to a lack of inductance. The investigation of alternative coreless coil plasma configurations resulted in coupling efficiencies up to 89% decreasing to 50% at 102 mbar for a toroidal plasma enclosed by toroidally spiraling coils.
{"title":"Toroidal CO2 Plasma Sources with Low- and High-Frequency Power Coupling Configurations for Improved Energy Transfer Efficiencies","authors":"E. J. Devid, W. Bongers, P. Groen, M. van Ginkel, S. Doyle, F. M. A. Smits, C. F. A. M. van Deursen, K. Serras, S. Labeur, M. A. Gleeson, M. C. M. van de Sanden","doi":"10.3390/plasma7030030","DOIUrl":"https://doi.org/10.3390/plasma7030030","url":null,"abstract":"Electrodeless Low-Frequency (LF)/Radio-Frequency (RF) plasma sources often suffer from low power coupling efficiencies due to the lack of overlapping field with the dynamic plasma load. However, the power supplies for these plasma sources typically have very high power efficiencies (>90%) and are more cost-effective compared to microwave sources. If the coupling efficiency to the plasma can be increased, these plasma sources offer a competitive technology for the sustainable electrification of the chemical industry. This work experimentally investigates five power coupling methods, applied to toroidal CO2 plasmas in a quartz vessel. The research was based on similar ferrite coupling as used in energy-efficient plasma lamps. The higher resistance of the CO2 plasma decreased the power coupling from 90% (for mercury-vapor plasma) to 66% at 1 mbar. High coupling efficiencies in LF/RF powered discharges can be achieved in two manners: either the inductance of the transformer cores can be increased, or the electromagnetic wave frequency can be increased. Furthermore, additional ferrite cores in parallel with the primary coils can be used to increase the impedance transformation. An experiment with six ferrite cores with a single primary winding in parallel, at a frequency of about 10 MHz and a power of 1 kW, showed that this frequency has a detrimental effect on the magnetic permeability and the losses in the ferrite result in a decrease of coupling to 33% at 1.5 mbar. At a frequency of 66 kHz with a nanocrystalline soft magnetic material core, a coupling of 89% was achieved in 1.5 mbar plasma for a power of 3.1 kW. This configuration exhibits decreasing coupling efficiencies at higher pressures since the plasma impedance increases, which again limits the coupling of the transformer due to a lack of inductance. The investigation of alternative coreless coil plasma configurations resulted in coupling efficiencies up to 89% decreasing to 50% at 102 mbar for a toroidal plasma enclosed by toroidally spiraling coils.","PeriodicalId":509984,"journal":{"name":"Plasma","volume":"58 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-07-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141809494","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Capacitively coupled plasma (CCP) discharges working at low pressure are widely used for the synthesis of thin films and the modification of the surface properties of materials. Due to their importance, considerable research was carried out over the years to understand their working mechanisms, and the physical properties of the CCP discharges were measured by many research groups, while simulations of their characteristics were often performed using both fluid and kinematic models. However, most of the simulation and characterization work found in the literature is focused on the discharge steady-state characteristics, since most of the applications rely on its properties, while less information is available on the early stages. In fact, the initial stages of CCP plasma discharges are of great importance to improve the understanding of their ignition process as well as to figure out the working mechanism of pulsed discharges, the use of which has increased in importance in recent years. In this work, a review of the results published in recent years concerning the physical mechanisms involved in the very first stages of low-pressure CCP discharges is presented, focusing on the first few microseconds of discharge time.
{"title":"A Review of Experimental Investigations into the Time Evolution of Low-Pressure Capacitively Coupled Plasmas in Their Early Stages of Development","authors":"Pietro Mandracci","doi":"10.3390/plasma7030029","DOIUrl":"https://doi.org/10.3390/plasma7030029","url":null,"abstract":"Capacitively coupled plasma (CCP) discharges working at low pressure are widely used for the synthesis of thin films and the modification of the surface properties of materials. Due to their importance, considerable research was carried out over the years to understand their working mechanisms, and the physical properties of the CCP discharges were measured by many research groups, while simulations of their characteristics were often performed using both fluid and kinematic models. However, most of the simulation and characterization work found in the literature is focused on the discharge steady-state characteristics, since most of the applications rely on its properties, while less information is available on the early stages. In fact, the initial stages of CCP plasma discharges are of great importance to improve the understanding of their ignition process as well as to figure out the working mechanism of pulsed discharges, the use of which has increased in importance in recent years. In this work, a review of the results published in recent years concerning the physical mechanisms involved in the very first stages of low-pressure CCP discharges is presented, focusing on the first few microseconds of discharge time.","PeriodicalId":509984,"journal":{"name":"Plasma","volume":"42 16","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-07-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141814879","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Tomas Bensadon, Mervi Mantsinen, Thomas Jonsson, D. Gallart, Xavier Sáez, J. Manyer
The PION code has been integrated into the European Transport Solver (ETS) transport workflow, and we present the first application to model Ion Cyclotron Resonance Frequency (ICRF) heating scenarios in the next-step fusion reactor ITER. We present results of predictive, self-consistent and time-dependent simulations where the resonant ion concentration is varied to study its effects on the performance, with a special emphasis on the resulting bulk ion heating and thermal ion temperature. We focus on two ICRF heating schemes, i.e., fundamental H minority heating in a 4He plasma at 2.65 T/7.5 MA and a three-ion ICRF scheme consisting of fundamental 3He heating in a H-4He plasma at 3.3 T/ 8.8 MA. The H minority heating scenario is found to result in strong absorption by resonant H ions as compared to competing absorption mechanisms and dominant background electron heating for H concentrations up to 10%. The highest H absorption of ∼80% of the applied ICRF power and highest ion temperature of ∼15 keV are obtained with an H concentration of 10%. For the three-ion scheme in 85%:15% H:4He plasma, PION+ETS predicts 3He absorption in the range of 21–65% for 3He concentrations in the range of 0.01–0.20%, with the highest 3He absorption at a 3He concentration of 0.20%.
PION 代码已被集成到欧洲传输求解器（ETS）传输工作流程中，我们首次将其应用于模拟下一步聚变反应堆 ITER 中的离子回旋共振频率（ICRF）加热情况。我们介绍了预测性、自洽性和随时间变化的模拟结果，其中共振离子浓度的变化研究了其对性能的影响，特别强调了由此产生的体离子加热和热离子温度。我们重点研究了两种 ICRF 加热方案，即在 2.65 T/7.5 MA 的 4He 等离子体中进行基本 H 少数加热，以及在 3.3 T/8.8 MA 的 H-4He 等离子体中进行由基本 3He 加热组成的三离子 ICRF 方案。研究发现，在 H 浓度高达 10%的情况下，与其他吸收机制和占主导地位的背景电子加热相比，H 少数加热方案会导致共振 H 离子的强烈吸收。当 H 浓度为 10%时，H 吸收率最高，达到所应用 ICRF 功率的 80%，离子温度最高，达到 15 keV。对于 85%:15% H:4He 等离子体中的三离子方案，PION+ETS 预测 3He 吸收率在 21-65% 之间，3He 浓度在 0.01-0.20% 之间，3He 吸收率在 0.20% 时最高。
{"title":"Analysis of ICRF Heating Schemes in ITER Non-Active Plasmas Using PION+ETS Integrated Modeling","authors":"Tomas Bensadon, Mervi Mantsinen, Thomas Jonsson, D. Gallart, Xavier Sáez, J. Manyer","doi":"10.3390/plasma7030028","DOIUrl":"https://doi.org/10.3390/plasma7030028","url":null,"abstract":"The PION code has been integrated into the European Transport Solver (ETS) transport workflow, and we present the first application to model Ion Cyclotron Resonance Frequency (ICRF) heating scenarios in the next-step fusion reactor ITER. We present results of predictive, self-consistent and time-dependent simulations where the resonant ion concentration is varied to study its effects on the performance, with a special emphasis on the resulting bulk ion heating and thermal ion temperature. We focus on two ICRF heating schemes, i.e., fundamental H minority heating in a 4He plasma at 2.65 T/7.5 MA and a three-ion ICRF scheme consisting of fundamental 3He heating in a H-4He plasma at 3.3 T/ 8.8 MA. The H minority heating scenario is found to result in strong absorption by resonant H ions as compared to competing absorption mechanisms and dominant background electron heating for H concentrations up to 10%. The highest H absorption of ∼80% of the applied ICRF power and highest ion temperature of ∼15 keV are obtained with an H concentration of 10%. For the three-ion scheme in 85%:15% H:4He plasma, PION+ETS predicts 3He absorption in the range of 21–65% for 3He concentrations in the range of 0.01–0.20%, with the highest 3He absorption at a 3He concentration of 0.20%.","PeriodicalId":509984,"journal":{"name":"Plasma","volume":"106 9","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-07-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141820618","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Josef Krása, Michal Krupka, Shubham Agarwal, Vincenzo Nassisi, Sushil Singh
This article provides an up-to-date overview of the problems associated with the detection of hot electrons escaping from laser-produced plasma and corresponding return current flowing from the ground to the target, which neutralises the positive charge occurring on the target due to the escaped electrons. In addition, the target holder system acts as an antenna emitting an electromagnetic pulse (EMP), which is powered by the return target. If the amount of positive charge generated on the target is equal to the amount of charge carried away from the plasma by the escaping electrons, the measurement of the return current makes it possible to determine this charge, and thus also the number of escaped electrons. Methods of return current detection in the mA–10 kA range is presented, and the corresponding charge is compared to the charge determined using calibrated magnetic electron energy analysers. The influence of grounded and insulated targets on the number of escaped electrons and EMP intensity is discussed. In addition to EMP detection, mapping of the electrical potential near the target is mentioned.
{"title":"Advanced Diagnostics of Electrons Escaping from Laser-Produced Plasma","authors":"Josef Krása, Michal Krupka, Shubham Agarwal, Vincenzo Nassisi, Sushil Singh","doi":"10.3390/plasma7020021","DOIUrl":"https://doi.org/10.3390/plasma7020021","url":null,"abstract":"This article provides an up-to-date overview of the problems associated with the detection of hot electrons escaping from laser-produced plasma and corresponding return current flowing from the ground to the target, which neutralises the positive charge occurring on the target due to the escaped electrons. In addition, the target holder system acts as an antenna emitting an electromagnetic pulse (EMP), which is powered by the return target. If the amount of positive charge generated on the target is equal to the amount of charge carried away from the plasma by the escaping electrons, the measurement of the return current makes it possible to determine this charge, and thus also the number of escaped electrons. Methods of return current detection in the mA–10 kA range is presented, and the corresponding charge is compared to the charge determined using calibrated magnetic electron energy analysers. The influence of grounded and insulated targets on the number of escaped electrons and EMP intensity is discussed. In addition to EMP detection, mapping of the electrical potential near the target is mentioned.","PeriodicalId":509984,"journal":{"name":"Plasma","volume":"123 20","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-05-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140985444","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
This work is an addition to the previously developed two-dimensional model of the shock–plasma interaction, extending it into the third dimension. The model can trace the evolution of the state of the hypersonic flow and the shock front refracted at a thermal discontinuity. The advantages of using the spherical coordinate system for this type of problem include increased transparency in interpreting the solution and a shortened calculation procedure, because all the changes to the front are reduced to one distortion component. Although the vorticity generation triggered at the interface is a consequence of the refraction and tied to the steep changes in the front, it is shown here that this is not because of an instant parameter jump at the interface due to refraction itself.
{"title":"Shock–Discharge Interaction Model Extended into the Third Dimension","authors":"Anna Markhotok","doi":"10.3390/plasma7020020","DOIUrl":"https://doi.org/10.3390/plasma7020020","url":null,"abstract":"This work is an addition to the previously developed two-dimensional model of the shock–plasma interaction, extending it into the third dimension. The model can trace the evolution of the state of the hypersonic flow and the shock front refracted at a thermal discontinuity. The advantages of using the spherical coordinate system for this type of problem include increased transparency in interpreting the solution and a shortened calculation procedure, because all the changes to the front are reduced to one distortion component. Although the vorticity generation triggered at the interface is a consequence of the refraction and tied to the steep changes in the front, it is shown here that this is not because of an instant parameter jump at the interface due to refraction itself.","PeriodicalId":509984,"journal":{"name":"Plasma","volume":" 39","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-05-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140990435","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
P. Hoffer, V. Prukner, G. Arora, R. Mušálek, Milan Šimek
This study utilizes the Kerr effect in the analysis of a pulsed electric field (intensity ~108 V/m, limited by the liquid dielectric strength) in deionized water at the sub-nanosecond time scale. The results provide information about voltage waveforms at the field-producing anode (160 kV peak, du/dt > 70 kV/ns). The analysis is based on detecting the phase shifts between measured and reference pulsed laser beams (pulse width, 35 ps; wavelength, 532 nm) using a Mach–Zehnder interferometer. The signal-to-noise ratio of the detected phase shift is maximized by an appropriate geometry of the field-producing anode, which creates a correctly oriented strong electric field along the interaction path and simultaneously does not electrically load the feeding transmission line. The described method has a spatial resolution of ~1 μm, and its time resolution is determined by the laser pulse duration.
{"title":"Determination of Highly Transient Electric Field in Water Using the Kerr Effect with Picosecond Resolution","authors":"P. Hoffer, V. Prukner, G. Arora, R. Mušálek, Milan Šimek","doi":"10.3390/plasma7020018","DOIUrl":"https://doi.org/10.3390/plasma7020018","url":null,"abstract":"This study utilizes the Kerr effect in the analysis of a pulsed electric field (intensity ~108 V/m, limited by the liquid dielectric strength) in deionized water at the sub-nanosecond time scale. The results provide information about voltage waveforms at the field-producing anode (160 kV peak, du/dt > 70 kV/ns). The analysis is based on detecting the phase shifts between measured and reference pulsed laser beams (pulse width, 35 ps; wavelength, 532 nm) using a Mach–Zehnder interferometer. The signal-to-noise ratio of the detected phase shift is maximized by an appropriate geometry of the field-producing anode, which creates a correctly oriented strong electric field along the interaction path and simultaneously does not electrically load the feeding transmission line. The described method has a spatial resolution of ~1 μm, and its time resolution is determined by the laser pulse duration.","PeriodicalId":509984,"journal":{"name":"Plasma","volume":"56 4","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-04-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140675892","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
A. Chaplygin, E. Simonenko, M. Kotov, Vladimir I. Sakharov, I. Lukomskii, Semen S. Galkin, A. F. Kolesnikov, A. Lysenkov, I. A. Nagornov, A. S. Mokrushin, N. Simonenko, N. T. Kuznetsov, M. Yakimov, A. Shemyakin, N. Solovyov
The short-term (5 min) exposure to the supersonic flow of carbon dioxide plasma on ultrahigh-temperature ceramics of HfB2-30vol.%SiC composition has been studied. It was shown that, when established on the surface at a temperature of 1615–1655 °C, the beginning of the formation of an oxidized layer takes place. Raman spectroscopy and scanning electron microscopy studies showed that the formation of a porous SiC-depleted region is not possible under the HfO2-SiO2 surface oxide layer. Numerical modeling based on the Navier–Stokes equations and experimental probe measurements of the test conditions were performed. The desirability of continuing systematic studies on the behavior of ultrahigh-temperature ZrB2/HfB2-SiC ceramics, including those doped with various components under the influence of high-enthalpy gas flows, was noted.
{"title":"Short-Term Oxidation of HfB2-SiC Based UHTC in Supersonic Flow of Carbon Dioxide Plasma","authors":"A. Chaplygin, E. Simonenko, M. Kotov, Vladimir I. Sakharov, I. Lukomskii, Semen S. Galkin, A. F. Kolesnikov, A. Lysenkov, I. A. Nagornov, A. S. Mokrushin, N. Simonenko, N. T. Kuznetsov, M. Yakimov, A. Shemyakin, N. Solovyov","doi":"10.3390/plasma7020017","DOIUrl":"https://doi.org/10.3390/plasma7020017","url":null,"abstract":"The short-term (5 min) exposure to the supersonic flow of carbon dioxide plasma on ultrahigh-temperature ceramics of HfB2-30vol.%SiC composition has been studied. It was shown that, when established on the surface at a temperature of 1615–1655 °C, the beginning of the formation of an oxidized layer takes place. Raman spectroscopy and scanning electron microscopy studies showed that the formation of a porous SiC-depleted region is not possible under the HfO2-SiO2 surface oxide layer. Numerical modeling based on the Navier–Stokes equations and experimental probe measurements of the test conditions were performed. The desirability of continuing systematic studies on the behavior of ultrahigh-temperature ZrB2/HfB2-SiC ceramics, including those doped with various components under the influence of high-enthalpy gas flows, was noted.","PeriodicalId":509984,"journal":{"name":"Plasma","volume":" 500","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-04-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140682613","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
A detailed review of the scientific literature was undertaken to examine the most recent developments in plasma processing in the field of medicine. The first part of the review includes a detailed breakdown of the different types of coatings that can be applied onto medical devices using plasma, with a specific focus on antimicrobial surfaces. The developments in plasma-deposited biocompatibles, drug delivery and adhesive coatings in 2023 are described, and specific applications in additive manufacturing are highlighted. The use of plasma and plasma-activated liquids as standalone therapeutics continues to evolve, and pertinent advances in this field are described. In addition, the combination of plasma medicine with conventional pharmaceutical interventions is reviewed, and key emerging trends are highlighted, including the use of plasma to enhance drug delivery directly into tissue. The potential synergies between plasma medicine and chemotherapeutics for oncology and infection treatment are a growing area, and recent advancements are noted. Finally, the use of plasma to control excess antibiotics and to intentionally degrade such materials in waste streams is described.
{"title":"Recent Developments in the Use of Plasma in Medical Applications","authors":"Fiona O’Neill, Liam O’Neill, Paula Bourke","doi":"10.3390/plasma7020016","DOIUrl":"https://doi.org/10.3390/plasma7020016","url":null,"abstract":"A detailed review of the scientific literature was undertaken to examine the most recent developments in plasma processing in the field of medicine. The first part of the review includes a detailed breakdown of the different types of coatings that can be applied onto medical devices using plasma, with a specific focus on antimicrobial surfaces. The developments in plasma-deposited biocompatibles, drug delivery and adhesive coatings in 2023 are described, and specific applications in additive manufacturing are highlighted. The use of plasma and plasma-activated liquids as standalone therapeutics continues to evolve, and pertinent advances in this field are described. In addition, the combination of plasma medicine with conventional pharmaceutical interventions is reviewed, and key emerging trends are highlighted, including the use of plasma to enhance drug delivery directly into tissue. The potential synergies between plasma medicine and chemotherapeutics for oncology and infection treatment are a growing area, and recent advancements are noted. Finally, the use of plasma to control excess antibiotics and to intentionally degrade such materials in waste streams is described.","PeriodicalId":509984,"journal":{"name":"Plasma","volume":"77 2","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-04-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140720143","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Micha Haase, Mudassir Ali Sayyed, Jan Langer, Danny Reuter, Harald Kuhn
In this study, we present the Method of Spectral Redundancy Reduction (MSRR) for analyzing OES (optical emission spectroscopy) data of dry etching processes based on the principles of spectral clustering. To achieve this, the OES data are transformed into abstract graph matrices whose associated eigenvectors directly indicate anomalies in the data set. We developed an approach that allows for the reduction in temporally resolved optical emission spectra from plasma structuring processes in such a way that individual emission lines can be algorithmically detected, which exhibit a temporal behavior different from the collective behavior of the temporally resolved overall spectrum. The proportion of emission lines that behave consistently throughout the entire process duration is not considered. Our work may find applications in which OES is used as a process-monitoring technique, especially for low-pressure plasma processing. The major benefit of the developed method is that the scale of the original data is kept, making physical interpretations possible despite data reductions.
在本研究中，我们介绍了基于光谱聚类原理的光谱冗余减少法（MSRR），用于分析干法蚀刻过程中的 OES（光学发射光谱）数据。为此，我们将 OES 数据转换为抽象图形矩阵，其相关特征向量可直接显示数据集中的异常情况。我们开发了一种方法，可以还原等离子体结构化过程产生的时间分辨光学发射光谱，从而可以通过算法检测到单个发射线，这些发射线的时间行为与时间分辨整体光谱的集体行为不同。我们没有考虑在整个过程中表现一致的发射线比例。我们的工作可能会应用于将 OES 用作过程监控技术，特别是低压等离子体加工。所开发方法的主要优点是保持了原始数据的比例，因此尽管数据有所减少，但仍可进行物理解释。
{"title":"About the Data Analysis of Optical Emission Spectra of Reactive Ion Etching Processes—The Method of Spectral Redundancy Reduction","authors":"Micha Haase, Mudassir Ali Sayyed, Jan Langer, Danny Reuter, Harald Kuhn","doi":"10.3390/plasma7010015","DOIUrl":"https://doi.org/10.3390/plasma7010015","url":null,"abstract":"In this study, we present the Method of Spectral Redundancy Reduction (MSRR) for analyzing OES (optical emission spectroscopy) data of dry etching processes based on the principles of spectral clustering. To achieve this, the OES data are transformed into abstract graph matrices whose associated eigenvectors directly indicate anomalies in the data set. We developed an approach that allows for the reduction in temporally resolved optical emission spectra from plasma structuring processes in such a way that individual emission lines can be algorithmically detected, which exhibit a temporal behavior different from the collective behavior of the temporally resolved overall spectrum. The proportion of emission lines that behave consistently throughout the entire process duration is not considered. Our work may find applications in which OES is used as a process-monitoring technique, especially for low-pressure plasma processing. The major benefit of the developed method is that the scale of the original data is kept, making physical interpretations possible despite data reductions.","PeriodicalId":509984,"journal":{"name":"Plasma","volume":"25 29","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-03-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140225885","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Ali Kazemi, McKayla J. Nicol, Sven Bilén, Girish S. Kirimanjeswara, Sean D. Knecht
Plasma medicine is an emerging field that applies the science and engineering of physical plasma to biomedical applications. Low-temperature plasma, also known as cold plasma, is generated via the ionization of atoms in a gas, generally via exposure to strong electric fields, and consists of ions, free radicals, and molecules at varying energy states. Plasmas generated at low temperatures (approximately room temperature) have been used for applications in dermatology, oncology, and anti-microbial strategies. Despite current and ongoing clinical use, the exact mechanisms of action and the full range of effects of cold plasma treatment on cells are only just beginning to be understood. Direct and indirect effects of plasma on immune cells have the potential to be utilized for various applications such as immunomodulation, anti-infective therapies, and regulating inflammation. In this review, we combine diverse expertise in the fields of plasma chemistry, device design, and immunobiology to cover the history and current state of plasma medicine, basic plasma chemistry and their implications, the effects of cold atmospheric plasma on host cells with their potential immunological consequences, future directions, and the outlook and recommendations for plasma medicine.
{"title":"Cold Atmospheric Plasma Medicine: Applications, Challenges, and Opportunities for Predictive Control","authors":"Ali Kazemi, McKayla J. Nicol, Sven Bilén, Girish S. Kirimanjeswara, Sean D. Knecht","doi":"10.3390/plasma7010014","DOIUrl":"https://doi.org/10.3390/plasma7010014","url":null,"abstract":"Plasma medicine is an emerging field that applies the science and engineering of physical plasma to biomedical applications. Low-temperature plasma, also known as cold plasma, is generated via the ionization of atoms in a gas, generally via exposure to strong electric fields, and consists of ions, free radicals, and molecules at varying energy states. Plasmas generated at low temperatures (approximately room temperature) have been used for applications in dermatology, oncology, and anti-microbial strategies. Despite current and ongoing clinical use, the exact mechanisms of action and the full range of effects of cold plasma treatment on cells are only just beginning to be understood. Direct and indirect effects of plasma on immune cells have the potential to be utilized for various applications such as immunomodulation, anti-infective therapies, and regulating inflammation. In this review, we combine diverse expertise in the fields of plasma chemistry, device design, and immunobiology to cover the history and current state of plasma medicine, basic plasma chemistry and their implications, the effects of cold atmospheric plasma on host cells with their potential immunological consequences, future directions, and the outlook and recommendations for plasma medicine.","PeriodicalId":509984,"journal":{"name":"Plasma","volume":"88 7","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-03-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140236746","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
京公网安备 11010802042870号
京ICP备2023020795号-1
扫码关注我们
求助内容：
应助结果提醒方式：