Characterization of the helicon plasma flux to the target of Proto-MPEX

Beers, C. J.; Lindquist, Elizabeth G.; Biewer, T. M.; Caneses, J. F.; Caughman, J. B. O.; Goulding, R. H.; Kafle, N.; Ray, H.; Showers, M.; Zinkle, S.J.; Rapp, J.

doi:10.1016/j.fusengdes.2018.11.056

Cited by 7 publications

(5 citation statements)

References 25 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…In the laboratory and industrial applications, plasma-surface interaction often plays a crucial role, either beneficial to the desired effect or counteracting it. As an illustration of the latter, the contact between the plasma and the reactor wall poses one of the main theoretical and engineering challenges in nuclear fusion [2,4,22,23]. From a practical perspective, the detrimental wall erosion is even expected to remain such a bottleneck in the final application of fusion reactors that liquid walls are currently considered as an attractive alternative [24,25].…”

Section: Plasma-surface Interaction Physics -An Overarching Domain Wh...mentioning

confidence: 99%

Multiscale modeling of plasma–surface interaction—General picture and a case study of Si and SiO2 etching by fluorocarbon-based plasmas

Vanraes

Venugopalan

Bogaerts

2021

Applied Physics Reviews

View full text Add to dashboard Cite

The physics and chemistry of plasma-surface interaction is a broad domain relevant to various applications and several natural processes, including plasma etching for microelectronics fabrication, plasma deposition, surface functionalization, nanomaterial synthesis, fusion reactors, and some astrophysical and meteorological phenomena. Due to their complex nature, each of these processes are generally investigated in separate subdomains, which are considered to have their own theoretical, modeling and experimental challenges. In this review, however, we want to emphasize the overarching nature of plasma-surface interaction physics and chemistry, by focusing on the general strategy for its computational simulation. In the first half of the review, we provide a menu card with standard and less standardized computational methods to be used for the multiscale modeling of the underlying processes. In the second half, we illustrate the benefits and potential of the multiscale modeling strategy with a case study of Si and SiO2 etching by fluorocarbon plasmas, and identify the gaps in knowledge still present on this intensely investigated plasma-material combination, both on a qualitative and quantitative level. Remarkably, the dominant etching mechanisms remain the least understood. The resulting new insights are of general relevance, for all plasmas and materials, including their various applications. We therefore hope to motivate computational and experimental scientists and engineers to collaborate more intensely on filling the existing gaps in knowledge. In this way, we expect that research will overcome a bottleneck stage in the development and optimization of multiscale models, and thus the fundamental understanding of plasma-surface interaction. TABLE OF CONTENTS wanderlust 3.3.2 Application-specific methods -specialize in the impossible 3.3.3 Machine learning -brainstorming by artificial intelligence 3.3.4 Plasma sheath modeling -matter's aura explained 3.4 Multiscale measuring -because nature is still the best simulation tool 4. PLASMA ETCHING -FROM SCRATCHING THE SURFACE TO GOING IN DEPTH 4.1 The multiscale plasma etching model -one example to represent them all 4.1.1 The need for a bottom-up approach -message in a bottleneck 4.1.2 Hybrid Plasma Equipment Model -example of a hybrid macroscale method 4.1.3 Plasma sheath module -example of a semi-analytical sheath method 4.1.4 Surface kinetics module -example of a deterministic description 4.1.5 Monte Carlo Feature Profile Model -example of a kinetic Monte Carlo method 4.1.6 Experimental benchmarking of the working principle -examples of multiscale measuring 4.1.7 Reactor geometry and operating conditions -example of a case study 4.2 How to implement the surface processes -example of atomistic modeling and measuring data 4.2.1 Elementary plasma-surface mechanisms -simplicity is the ultimate sophistication 4.2.2 Design of the surface chemistry set -a mosaic of quantum data 4.3 Benchmarking the simulation model -bringing uncertainties to the surface 5.

show abstract

Section: Plasma-surface Interaction Physics -An Overarching Domain Wh...mentioning

confidence: 99%

Multiscale modeling of plasma–surface interaction—General picture and a case study of Si and SiO2 etching by fluorocarbon-based plasmas

Vanraes

Venugopalan

Bogaerts

2021

Applied Physics Reviews

View full text Add to dashboard Cite

show abstract

“…Sufficient coverage of the DIII-D first wall with SiC could have the added benefit of reducing the C impurity background in the plasma, allowing for more reactor-relevant studies of radiative optimization. High-fluence exposures of neutrondamaged SiC should also commence immediately on test stands and linear plamsa devices to evaluate the power handling and erosion properties of SiC in more detail; fortunately, initial effors are already underway [11] [59].…”

Section: Discussionmentioning

confidence: 99%

Evaluation of silicon carbide as a divertor armor material in DIII-D H-mode discharges

Abrams¹,

Bringuier²,

Thomas³

et al. 2021

Nucl. Fusion

View full text Add to dashboard Cite

Silicon carbide (SiC) represents a promising but largely untested plasma-facing material (PFM) for next-step fusion devices. In this work, an analytic mixed-material erosion model is developed by calculating the physical (via SDTrimSP) and chemical (via empirical scalings) sputtering yield from SiC, Si, and C. The Si content in the near-surface SiC layer is predicted to increase during D plasma bombardment due to more efficient physical and chemical sputtering of C relative to Si. Silicon erosion from SiC thereby occurs primarily from sputtering of the enriched Si layer, rather than directly from the SiC itself. SiC coatings on ATJ graphite, manufactured via chemical vapor deposition, were exposed to repeated H-mode plasma discharges in the DIII-D tokamak to test this model. The qualitative trends from analytic modeling are reproduced by the experimental measurements, obtained via spectroscopic inference using the S/XB method. Quantitatively the model slightly underpredicts measured erosion rates, which is attributed to uncertainties in the ion impact angle distribution, as well as the effect of edge-localized modes. After exposure, minimal changes to the macroscopic or microscopic surface morphology of the SiC coatings were observed. Compositional analysis reveals Si enrichment of about 10%, in line with expectations from the erosion model. Extrapolating to a DEMO-type device, an order-of-magnitude decrease in impurity sourcing, and up to a factor of 2 decrease in impurity radiation, is expected with SiC walls, relative to graphite, if low C plasma impurity content can be achieved. These favorable erosion properties motivate further investigations of SiC as a low-Z, non-metallic PFM.

show abstract

“…Re-crystallization of W on thin coupons has been observed [12]. Figure 5 shows a photograph of a SiC target, which exhibits a significant step from the masked to eroded region [13]. Post mortem DH measurements indicate this step is ∼ 1.4 µm high, as shown in figure 5.…”

Section: Proto-mpex Erosion Observationsmentioning

confidence: 90%

Considerations for in situ, real time measurement of plasma-material interactions using Digital Holographic imaging

et al. 2020

Self Cite

View full text Add to dashboard Cite

Characterization of the helicon plasma flux to the target of Proto-MPEX

Cited by 7 publications

References 25 publications

Multiscale modeling of plasma–surface interaction—General picture and a case study of Si and SiO2 etching by fluorocarbon-based plasmas

Multiscale modeling of plasma–surface interaction—General picture and a case study of Si and SiO2 etching by fluorocarbon-based plasmas

Evaluation of silicon carbide as a divertor armor material in DIII-D H-mode discharges

Considerations for in situ, real time measurement of plasma-material interactions using Digital Holographic imaging

Contact Info

Product

Resources

About