The problem of Langmuir probe data deformation due to RF pickup by the probe is treated through a computer simulation method. It is pointed out that proper RF compensations can be obtained by treatment of the Langmuir probe raw data through the use of computer software. It is demonstrated that correct, RF unaffected probe I–V characteristics can be accurately reproduced from the RF contaminated data. This eliminates the need for the use of any filters or other hardware procedures. User friendly matlab based software is presented. The software automatically retrieves the correct RF I–V characteristics for single Langmuir probe data which consequently allows for proper evaluation of plasma parameters such as the plasma electron temperature, electron number density and the electron energy distribution function (EEDF) Program summaryProgram title: RF CompensationCatalogue identifier: AEQR_v1_0Program summary URL:http://cpc.cs.qub.ac.uk/summaries/AEQR_v1_0.htmlProgram obtainable from: CPC Program Library, Queen’s University, Belfast, N. IrelandLicensing provisions: Copyright (c) 2009, aasim AzoozAll rights reserved.Redistribution and use in source and binary forms, with or without modification, are permitted provided that the following conditions are met: •Redistributions of source code must retain the above copyright notice, this list of conditions and the following disclaimer.•Redistributions in binary form must reproduce the above copyright notice, this list of conditions and the following disclaimer in the documentation and/or other materials provided with the distribution. THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS “AS IS” AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.No. of lines in distributed program, including test data, etc.: 1269No. of bytes in distributed program, including test data, etc.: 179353Distribution format: tar.gzProgramming language: MATLAB 6.5 or higher.Computer: Any laptop or desktop.Operating system: Windows XP.RAM: Bytes 512 KClassification: 19.Nature of problem:In RF plasma Langmuir probe diagnostics, the probe I–V characteristics obtained experimentally does not represent the true I–V. This is because the probe picks up some RF plasma voltage which modulates the applied bias voltage and causes a current flow that corresponds to the RF affected bias rather that the actual DC bias. This if untreated can lead to false results for the values of plasma parameters derived from the obtained I–V. Several hardware based methods are used to perform such correction (compensation).Solution method:The suggested method is based on filtration of raw uncompensated I–V data through software operation rather than hardware based filtrations which have their limitations.Running time:A few milliseconds.
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