Micro-trench measurements of the net deposition of carbon impurity ions in the DIII-D divertor and the resulting suppression of surface erosion

Abe, S.; Skinner, C. H.; Bykov, I.; Guterl, J.; Lasa, A.; Yeh, Y. W.; Coburn, J.; Rudakov, D. L.; Lasnier, C. J.; Wang, H. Q.; McLean, A. G.; Abrams, T.; Koel, B. E.

doi:10.1088/1402-4896/ac2af4

Title: Micro-trench measurements of the net deposition of carbon impurity ions in the DIII-D divertor and the resulting suppression of surface erosion

Abstract

In this work, we report carbon impurity ion incident angles and deposition rates, along with silicon erosion rates, from measurements of micro-engineered trenches on a silicon surface exposed to L-mode deuterium plasmas at the DIII-D divertor. Post exposure ex-situ analysis determined elemental maps and concentrations, carbon deposition thicknesses, and erosion of silicon surfaces. Carbon deposition profiles on the trench floor showed carbon ion shadowing that was consistent with ERO calculations of average carbon ion angle distributions (IADs) for both polar and azimuthal angles. Measured silicon net erosion rates negatively correlated with the deposited carbon concentration at different locations. Differential erosion of surfaces on two different ion-downstream trench slope structures suggested that carbon deposition rate is affected by the carbon ion incident angle and significantly suppressed the surface erosion. The results suggest the C impurity ion incident angles, determined by the IADs and surface morphology, strongly affect erosion rates as well as the main ion (D, T, He) incident angles.

Authors:

^[1]; Skinner, C. H. ^[2]; Bykov, I. ^[3];

^[4];

^[5]; Yeh, Y. W. ^[6];

^[7];

^[3]; Lasnier, C. J. ^[8];

^[4]; McLean, A. G. ^[8];

^[4]; Koel, B. E. ^[1]

Princeton Univ., NJ (United States)
Princeton Plasma Physics Lab. (PPPL), Princeton, NJ (United States)
Univ. of California, San Diego, CA (United States)
General Atomics, San Diego, CA (United States)
Univ. of Tennessee, Knoxville, TN (United States)
Rutgers Univ., Piscataway, NJ (United States)
Sandia National Lab. (SNL-CA), Livermore, CA (United States)
Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

Publication Date:: Mon Oct 11 00:00:00 EDT 2021

Research Org.:: Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Sandia National Laboratories, SNL California; Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

Sponsoring Org.:: USDOE National Nuclear Security Administration (NNSA); USDOE Office of Science (SC), Fusion Energy Sciences (FES); National Science Foundation (NSF)

OSTI Identifier:: 1827617

Alternate Identifier(s):: OSTI ID: 1877328

Report Number(s):: SAND-2021-12749J; LLNL-JRNL-836401
Journal ID: ISSN 0031-8949; 700851; TRN: US2215971

Grant/Contract Number:: NA0003525; AC02-09CH11466; FC02-04ER54698; AC52-07NA27344; FG02-07ER54917; DMR-2011750

Resource Type:: Accepted Manuscript

Journal Name:: Physica Scripta

Additional Journal Information:: Journal Volume: 96; Journal Issue: 12; Journal ID: ISSN 0031-8949

Publisher:: IOP Publishing

Country of Publication:: United States

Language:: English

Subject:: 70 PLASMA PHYSICS AND FUSION TECHNOLOGY; Plasma-material interaction; Carbon Impurity; Ion incident angle; Erosion; Deposition; Sheath; Divertor; DiMES; Surface analysis

Citation Formats


                    Abe, S., Skinner, C. H., Bykov, I., Guterl, J., Lasa, A., Yeh, Y. W., Coburn, J., Rudakov, D. L., Lasnier, C. J., Wang, H. Q., McLean, A. G., Abrams, T., and Koel, B. E. Micro-trench measurements of the net deposition of carbon impurity ions in the DIII-D divertor and the resulting suppression of surface erosion.  United States: N. p., 2021. 
Web.  doi:10.1088/1402-4896/ac2af4.

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                    Abe, S., Skinner, C. H., Bykov, I., Guterl, J., Lasa, A., Yeh, Y. W., Coburn, J., Rudakov, D. L., Lasnier, C. J., Wang, H. Q., McLean, A. G., Abrams, T., & Koel, B. E. Micro-trench measurements of the net deposition of carbon impurity ions in the DIII-D divertor and the resulting suppression of surface erosion.  United States.  https://doi.org/10.1088/1402-4896/ac2af4

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                    Abe, S., Skinner, C. H., Bykov, I., Guterl, J., Lasa, A., Yeh, Y. W., Coburn, J., Rudakov, D. L., Lasnier, C. J., Wang, H. Q., McLean, A. G., Abrams, T., and Koel, B. E. Mon .  
"Micro-trench measurements of the net deposition of carbon impurity ions in the DIII-D divertor and the resulting suppression of surface erosion".  United States.  https://doi.org/10.1088/1402-4896/ac2af4.  https://www.osti.gov/servlets/purl/1827617.

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@article{osti_1827617,

  title        = {Micro-trench measurements of the net deposition of carbon impurity ions in the DIII-D divertor and the resulting suppression of surface erosion},

  author       = {Abe, S. and Skinner, C. H. and Bykov, I. and Guterl, J. and Lasa, A. and Yeh, Y. W. and Coburn, J. and Rudakov, D. L. and Lasnier, C. J. and Wang, H. Q. and McLean, A. G. and Abrams, T. and Koel, B. E.},

  abstractNote = {In this work, we report carbon impurity ion incident angles and deposition rates, along with silicon erosion rates, from measurements of micro-engineered trenches on a silicon surface exposed to L-mode deuterium plasmas at the DIII-D divertor. Post exposure ex-situ analysis determined elemental maps and concentrations, carbon deposition thicknesses, and erosion of silicon surfaces. Carbon deposition profiles on the trench floor showed carbon ion shadowing that was consistent with ERO calculations of average carbon ion angle distributions (IADs) for both polar and azimuthal angles. Measured silicon net erosion rates negatively correlated with the deposited carbon concentration at different locations. Differential erosion of surfaces on two different ion-downstream trench slope structures suggested that carbon deposition rate is affected by the carbon ion incident angle and significantly suppressed the surface erosion. The results suggest the C impurity ion incident angles, determined by the IADs and surface morphology, strongly affect erosion rates as well as the main ion (D, T, He) incident angles.},

  doi          = {10.1088/1402-4896/ac2af4},

  journal      = {Physica Scripta},

  number       = 12,

  volume       = 96,

  place        = {United States},

  year         = {Mon Oct 11 00:00:00 EDT 2021},

  month        = {Mon Oct 11 00:00:00 EDT 2021}

}

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Experimental verification of ion impact angle distribution at divertor surfaces using micro-engineered targets on DiMES at DIII-D
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Evaluation of silicon carbide as a divertor armor material in DIII-D H-mode discharges
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Title: Micro-trench measurements of the net deposition of carbon impurity ions in the DIII-D divertor and the resulting suppression of surface erosion

Abstract

Citation Formats

Impacts of impurity flux on erosion and deposition of carbon/tungsten rough surfaces journal, March 2021

Advances in understanding of high- Z material erosion and re-deposition in low- Z wall environment in DIII-D journal, March 2017

ERO modeling and analysis of tungsten erosion and migration from a toroidally symmetric source in the DIII-D divertor journal, November 2019

Plasma-wall interaction and plasma behaviour in the non-boronised all tungsten ASDEX Upgrade journal, June 2009

ERO modelling of tungsten erosion and re-deposition in EAST L mode discharges journal, September 2017

SRIM – The stopping and range of ions in matter (2010) journal, June 2010

Impact of gyro-motion and sheath acceleration on the flux distribution on rough surfaces journal, August 2010

Experimental verification of ion impact angle distribution at divertor surfaces using micro-engineered targets on DiMES at DIII-D journal, June 2021

Evaluation of silicon carbide as a divertor armor material in DIII-D H-mode discharges journal, April 2021

Erosion characterization of SiC and Ti3SiC2 on DIII-D using focused ion beam micro-trenches journal, May 2019

The inter-ELM tungsten erosion profile in DIII-D H-mode discharges and benchmarking with ERO+OEDGE modeling journal, April 2017

Imaging low-dimensional nanostructures by very low voltage scanning electron microscopy: ultra-shallow topography and depth-tunable material contrast journal, November 2019

Simulation of gross and net erosion of high- Z materials in the DIII-D divertor journal, December 2015

Measurement and modeling of aluminum sputtering and ionization in the DIII-D divertor including magnetic pre-sheath effects journal, August 2018

ELM-resolved divertor erosion in the JET ITER-Like Wall journal, January 2016

Overview of the recent DiMES and MiMES experiments in DIII-D journal, December 2009

Multi-physics modeling of the long-term evolution of helium plasma exposed surfaces journal, January 2020

Tungsten erosion by impurities and redeposition: focus on the magnetised sheath journal, February 2017

Impacts of impurity flux on erosion and deposition of carbon/tungsten rough surfaces
journal, March 2021

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journal, June 2009

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journal, June 2010

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journal, August 2010

Experimental verification of ion impact angle distribution at divertor surfaces using micro-engineered targets on DiMES at DIII-D
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journal, April 2021

Erosion characterization of SiC and Ti3SiC2 on DIII-D using focused ion beam micro-trenches
journal, May 2019

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journal, April 2017

Imaging low-dimensional nanostructures by very low voltage scanning electron microscopy: ultra-shallow topography and depth-tunable material contrast
journal, November 2019

Simulation of gross and net erosion of high- Z materials in the DIII-D divertor
journal, December 2015

Measurement and modeling of aluminum sputtering and ionization in the DIII-D divertor including magnetic pre-sheath effects
journal, August 2018

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journal, January 2016

Overview of the recent DiMES and MiMES experiments in DIII-D
journal, December 2009

Multi-physics modeling of the long-term evolution of helium plasma exposed surfaces
journal, January 2020

Tungsten erosion by impurities and redeposition: focus on the magnetised sheath
journal, February 2017