{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,30]],"date-time":"2026-09-30T20:00:20Z","timestamp":1790798420217,"version":"4.1.0"},"reference-count":33,"publisher":"MDPI AG","issue":"8","license":[{"start":{"date-parts":[[2026,7,25]],"date-time":"2026-07-25T00:00:00Z","timestamp":1784937600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Ministry of Education","award":["2026-RISE-02-004-1-1-8-1"],"award-info":[{"award-number":["2026-RISE-02-004-1-1-8-1"]}]},{"award":["2026-RISE-02-004-1-1-8-1"],"award-info":[{"award-number":["2026-RISE-02-004-1-1-8-1"]}],"id":[{"id":"https:\/\/ror.org\/01p262204","id-type":"ROR","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Micromachines"],"abstract":"<jats:p>Low-damage plasma processing of atomically thin MoS2 requires simultaneous control of ion species, energy, and incident angle, yet the discharge mechanisms governing Ar\/O2 plasma and their connection to surface damage remain insufficiently understood. Here, we investigate the effect of the Ar\/O2 mixing ratio on the spatial distributions of charged particles, the plasma potential, and the substrate-incident ion energy and angular distributions in a low-voltage, single-frequency capacitively coupled plasma using a two-dimensional particle-in-cell Monte Carlo collision (PIC-MCC) simulation. At a fixed pressure of 50 mTorr with the Ar\/O2 ratio varied from 9:1 to 2:8, the ion energy and angular distributions were collected at the center and edge of the powered electrode. Increasing the oxygen fraction reduced the electron density while enhancing the O\u2212 density and electronegativity, driving an electropositive-to-electronegative transition near 8:2, and shifted the dominant positive ion from Ar+ to O2+, with O+ remaining minor owing to charge-exchange loss. The plasma potential and ion-energy peaks generally increased with the oxygen fraction but showed nonmonotonic dependence, while radial edge fields tilted and broadened the angular distributions. To link the ion and oxygen-radical fluxes to MoS2 processing without assuming uncertain surface-response coefficients, we interpreted the ion and oxygen-radical fluxes through a phenomenological two-channel surface-reaction scheme, introducing a damaging ion fraction and a radical-to-ion flux ratio. Their opposing trends reveal an intrinsic trade-off, indicating that an intermediate O2 fraction offers a more favorable low-damage window than either Ar-rich or strongly oxygen-rich conditions.<\/jats:p>","DOI":"10.3390\/mi17080891","type":"journal-article","created":{"date-parts":[[2026,7,27]],"date-time":"2026-07-27T16:11:56Z","timestamp":1785168716000},"page":"891","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":1,"title":["Plasma-Side Analysis of Chemical-to-Ion Flux Balance and Ion Energy-Angular Distributions in Ar\/O2 Capacitively Coupled Plasmas for MoS2-Relevant Low-Damage Patterning"],"prefix":"10.3390","volume":"17","author":[{"ORCID":"https:\/\/orcid.org\/0009-0005-6022-1395","authenticated-orcid":false,"given":"Cheol Woong","family":"Kim","sequence":"first","affiliation":[{"name":"Department of Electrical Engineering, Pusan National University, Busan 46241, Republic of Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0009-2815-6967","authenticated-orcid":false,"given":"Geonwoo","family":"Park","sequence":"additional","affiliation":[{"name":"Memory Equipment and Component Technology Team, Samsung Electronics Company, Ltd., Hwaseong 18448, Republic of Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3401-3355","authenticated-orcid":false,"given":"Hae June","family":"Lee","sequence":"additional","affiliation":[{"name":"Department of Electrical Engineering, Pusan National University, Busan 46241, Republic of Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2026,7,25]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"05C203","DOI":"10.1116\/1.4993602","article-title":"Plasma\u2013surface interactions at the atomic scale for patterning metals","volume":"35","author":"Altieri","year":"2017","journal-title":"J. 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