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Title: Diagnostics of hydrogen plasma with in situ optical emission and silicon probes

Abstract

In this work, an approach has been adopted to explore plasma properties by combining an in situ optical emission technique with a contact angle measurement. Hydrogen plasma was generated with a radio-frequency power source. The plasma parameters such as number densities and temperatures were derived from the optical emission spectroscopic data. Small silicon chips were placed at various positions inside a discharge tube as probes for the plasma conditions. The hydrogen-plasma-treated silicon chip surfaces were characterized with the contact angle measurement method. The change of wettability on the silicon surface was observed with various plasma treatment times. The spectroscopic information about the plasma is correlated with the results of the surface characterization. It is found that the rate of the increasing hydrophilicity is sensitive to the amount of helium added and the location in the discharge tube. A simple model describing the relation between the surface coverage area of water droplet and the variation of contact angle has been established. We have proposed plasma excitation and reaction mechanisms for the observed correlation between plasma temperatures and the wettability of the silicon surface. It shows that small silicon chips can serve as 'litmus tests' for the plasma conditions without introducing toomore » much perturbation.« less

Authors:
;  [1]
  1. Department of Chemistry and Center for Nano-Technology, Chung Yuan Christian University, 200 Jongbei Road, Jhongli City, Taoyuan County 32023, Taiwan (China)
Publication Date:
OSTI Identifier:
20719797
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Applied Physics; Journal Volume: 98; Journal Issue: 10; Other Information: DOI: 10.1063/1.2132517; (c) 2005 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
70 PLASMA PHYSICS AND FUSION TECHNOLOGY; DROPLETS; ELECTRON TEMPERATURE; EXCITATION; GAS DISCHARGE TUBES; HELIUM; HYDROGEN; ION TEMPERATURE; PHOTON EMISSION; PLASMA; PLASMA DENSITY; RADIOWAVE RADIATION; REACTION KINETICS; SEMICONDUCTOR MATERIALS; SILICON; SURFACE TREATMENTS; SURFACES; TUBES; WALL EFFECTS; WATER; WETTABILITY

Citation Formats

Lee, Szetsen, and Chung, Y.-J. Diagnostics of hydrogen plasma with in situ optical emission and silicon probes. United States: N. p., 2005. Web. doi:10.1063/1.2132517.
Lee, Szetsen, & Chung, Y.-J. Diagnostics of hydrogen plasma with in situ optical emission and silicon probes. United States. doi:10.1063/1.2132517.
Lee, Szetsen, and Chung, Y.-J. Tue . "Diagnostics of hydrogen plasma with in situ optical emission and silicon probes". United States. doi:10.1063/1.2132517.
@article{osti_20719797,
title = {Diagnostics of hydrogen plasma with in situ optical emission and silicon probes},
author = {Lee, Szetsen and Chung, Y.-J.},
abstractNote = {In this work, an approach has been adopted to explore plasma properties by combining an in situ optical emission technique with a contact angle measurement. Hydrogen plasma was generated with a radio-frequency power source. The plasma parameters such as number densities and temperatures were derived from the optical emission spectroscopic data. Small silicon chips were placed at various positions inside a discharge tube as probes for the plasma conditions. The hydrogen-plasma-treated silicon chip surfaces were characterized with the contact angle measurement method. The change of wettability on the silicon surface was observed with various plasma treatment times. The spectroscopic information about the plasma is correlated with the results of the surface characterization. It is found that the rate of the increasing hydrophilicity is sensitive to the amount of helium added and the location in the discharge tube. A simple model describing the relation between the surface coverage area of water droplet and the variation of contact angle has been established. We have proposed plasma excitation and reaction mechanisms for the observed correlation between plasma temperatures and the wettability of the silicon surface. It shows that small silicon chips can serve as 'litmus tests' for the plasma conditions without introducing too much perturbation.},
doi = {10.1063/1.2132517},
journal = {Journal of Applied Physics},
number = 10,
volume = 98,
place = {United States},
year = {Tue Nov 15 00:00:00 EST 2005},
month = {Tue Nov 15 00:00:00 EST 2005}
}
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