Effect of water vapor on plasma processing at atmospheric pressure

Polymer etching and surface modification by an Ar/H2O plasma jet

Pingshan Luan, V. S.Santosh K. Kondeti, Andrew J. Knoll, Peter J Bruggeman, Gottlieb S. Oehrlein

Research output: Contribution to journalArticle

1 Citation (Scopus)

Abstract

The authors evaluate the effect of water vapor on the plasma processing of materials using a model system consisting of a well-characterized radio-frequency plasma jet, controlled gaseous environment, and polystyrene as target material. The authors find that the effluent of Ar/H2O plasma jet is capable of (1) etching polymers with relatively high etch rate and (2) weakly oxidizing the etched polymer surface by forming O containing moieties. When increasing the treatment distance between the polymer and the Ar/H2O plasma, the authors find that the polymer etch rate drops exponentially, whereas the O elemental composition of the etched surface shows a maximum at intermediate treatment distance. The OH density in the Ar/H2O jet was measured near the substrate surface by laser induced fluorescence, and the density change of the OH radicals with treatment distance is found to be consistent with the exponential decrease of polymer etch rate, which indicates that OH may play a dominant role in the polymer etching process. A control experiment of Ar/H2 plasma shows that the observed fast polymer etching by Ar/H2O plasma cannot be attributed to H atoms. By correlating the OH flux with the polymer etch rate, the authors estimated the etching reaction coefficient of OH radicals (number of C atoms removed per OH radical from the gas phase) as ∼10-2. The polymer etch rate of Ar/H2O plasma is enhanced as the substrate temperature is lowered, which can be explained by the enhanced surface adsorption of gas phase species. For the same molecular admixture concentration and plasma power, the authors find that Ar/H2O/O2 plasma has much reduced etching efficiency compared to either Ar/H2O or Ar/O2 plasma.

Original languageEnglish (US)
Article number15092272
JournalJournal of Vacuum Science and Technology A: Vacuum, Surfaces and Films
Volume37
Issue number3
DOIs
StatePublished - May 1 2019

Fingerprint

Plasma applications
Plasma jets
Steam
plasma jets
Water vapor
Atmospheric pressure
Surface treatment
water vapor
Etching
atmospheric pressure
Polymers
etching
polymers
Plasmas
Gases
vapor phases
Atoms
effluents
Polystyrenes
Substrates

Cite this

Effect of water vapor on plasma processing at atmospheric pressure : Polymer etching and surface modification by an Ar/H2O plasma jet. / Luan, Pingshan; Kondeti, V. S.Santosh K.; Knoll, Andrew J.; Bruggeman, Peter J; Oehrlein, Gottlieb S.

In: Journal of Vacuum Science and Technology A: Vacuum, Surfaces and Films, Vol. 37, No. 3, 15092272, 01.05.2019.

Research output: Contribution to journalArticle

@article{4fe348980af541339d989c548bd95e54,
title = "Effect of water vapor on plasma processing at atmospheric pressure: Polymer etching and surface modification by an Ar/H2O plasma jet",
abstract = "The authors evaluate the effect of water vapor on the plasma processing of materials using a model system consisting of a well-characterized radio-frequency plasma jet, controlled gaseous environment, and polystyrene as target material. The authors find that the effluent of Ar/H2O plasma jet is capable of (1) etching polymers with relatively high etch rate and (2) weakly oxidizing the etched polymer surface by forming O containing moieties. When increasing the treatment distance between the polymer and the Ar/H2O plasma, the authors find that the polymer etch rate drops exponentially, whereas the O elemental composition of the etched surface shows a maximum at intermediate treatment distance. The OH density in the Ar/H2O jet was measured near the substrate surface by laser induced fluorescence, and the density change of the OH radicals with treatment distance is found to be consistent with the exponential decrease of polymer etch rate, which indicates that OH may play a dominant role in the polymer etching process. A control experiment of Ar/H2 plasma shows that the observed fast polymer etching by Ar/H2O plasma cannot be attributed to H atoms. By correlating the OH flux with the polymer etch rate, the authors estimated the etching reaction coefficient of OH radicals (number of C atoms removed per OH radical from the gas phase) as ∼10-2. The polymer etch rate of Ar/H2O plasma is enhanced as the substrate temperature is lowered, which can be explained by the enhanced surface adsorption of gas phase species. For the same molecular admixture concentration and plasma power, the authors find that Ar/H2O/O2 plasma has much reduced etching efficiency compared to either Ar/H2O or Ar/O2 plasma.",
author = "Pingshan Luan and Kondeti, {V. S.Santosh K.} and Knoll, {Andrew J.} and Bruggeman, {Peter J} and Oehrlein, {Gottlieb S.}",
year = "2019",
month = "5",
day = "1",
doi = "10.1116/1.5092272",
language = "English (US)",
volume = "37",
journal = "Journal of Vacuum Science and Technology A",
issn = "0734-2101",
publisher = "AVS Science and Technology Society",
number = "3",

}

TY - JOUR

T1 - Effect of water vapor on plasma processing at atmospheric pressure

T2 - Polymer etching and surface modification by an Ar/H2O plasma jet

AU - Luan, Pingshan

AU - Kondeti, V. S.Santosh K.

AU - Knoll, Andrew J.

AU - Bruggeman, Peter J

AU - Oehrlein, Gottlieb S.

PY - 2019/5/1

Y1 - 2019/5/1

N2 - The authors evaluate the effect of water vapor on the plasma processing of materials using a model system consisting of a well-characterized radio-frequency plasma jet, controlled gaseous environment, and polystyrene as target material. The authors find that the effluent of Ar/H2O plasma jet is capable of (1) etching polymers with relatively high etch rate and (2) weakly oxidizing the etched polymer surface by forming O containing moieties. When increasing the treatment distance between the polymer and the Ar/H2O plasma, the authors find that the polymer etch rate drops exponentially, whereas the O elemental composition of the etched surface shows a maximum at intermediate treatment distance. The OH density in the Ar/H2O jet was measured near the substrate surface by laser induced fluorescence, and the density change of the OH radicals with treatment distance is found to be consistent with the exponential decrease of polymer etch rate, which indicates that OH may play a dominant role in the polymer etching process. A control experiment of Ar/H2 plasma shows that the observed fast polymer etching by Ar/H2O plasma cannot be attributed to H atoms. By correlating the OH flux with the polymer etch rate, the authors estimated the etching reaction coefficient of OH radicals (number of C atoms removed per OH radical from the gas phase) as ∼10-2. The polymer etch rate of Ar/H2O plasma is enhanced as the substrate temperature is lowered, which can be explained by the enhanced surface adsorption of gas phase species. For the same molecular admixture concentration and plasma power, the authors find that Ar/H2O/O2 plasma has much reduced etching efficiency compared to either Ar/H2O or Ar/O2 plasma.

AB - The authors evaluate the effect of water vapor on the plasma processing of materials using a model system consisting of a well-characterized radio-frequency plasma jet, controlled gaseous environment, and polystyrene as target material. The authors find that the effluent of Ar/H2O plasma jet is capable of (1) etching polymers with relatively high etch rate and (2) weakly oxidizing the etched polymer surface by forming O containing moieties. When increasing the treatment distance between the polymer and the Ar/H2O plasma, the authors find that the polymer etch rate drops exponentially, whereas the O elemental composition of the etched surface shows a maximum at intermediate treatment distance. The OH density in the Ar/H2O jet was measured near the substrate surface by laser induced fluorescence, and the density change of the OH radicals with treatment distance is found to be consistent with the exponential decrease of polymer etch rate, which indicates that OH may play a dominant role in the polymer etching process. A control experiment of Ar/H2 plasma shows that the observed fast polymer etching by Ar/H2O plasma cannot be attributed to H atoms. By correlating the OH flux with the polymer etch rate, the authors estimated the etching reaction coefficient of OH radicals (number of C atoms removed per OH radical from the gas phase) as ∼10-2. The polymer etch rate of Ar/H2O plasma is enhanced as the substrate temperature is lowered, which can be explained by the enhanced surface adsorption of gas phase species. For the same molecular admixture concentration and plasma power, the authors find that Ar/H2O/O2 plasma has much reduced etching efficiency compared to either Ar/H2O or Ar/O2 plasma.

UR - http://www.scopus.com/inward/record.url?scp=85065652263&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=85065652263&partnerID=8YFLogxK

U2 - 10.1116/1.5092272

DO - 10.1116/1.5092272

M3 - Article

VL - 37

JO - Journal of Vacuum Science and Technology A

JF - Journal of Vacuum Science and Technology A

SN - 0734-2101

IS - 3

M1 - 15092272

ER -