Title Alternative Large-scale vortical structure detection using microphone array in a semiconductor single wafer spin cleaner
FullText URL TransJSME_83_845_2017.pdf
Author KOUCHI, Toshinori| MIYOSHI, Yuki| NAKANO, Yusuke| NAGATA, Yasunori| YANASE, Shinichiro|
Abstract Fluctuating pressure (p’ ) of a large-scale vortical structure generated in a semiconductor single wafer spin cleaner was detected by using microphone array. Twelve microphones were installed on the exhaust cover under the rotating disk of the cleaner with their interval of 7.5° or 15°. Power spectrum densities (PSD) of p’ were compared with those of fluctuating velocity measured by PIV for various rotation angular velocities to identify fluctuations due to convection of the large-scale vortical structure. Good agreement of PSDs indicates that the large-scale structure could be detected by using microphone. Cross-correlation of p’ measured at different positions revealed that the large-scale structure convected to the downstream in the rotational direction of the disk. The convection speed was about 12 % of the angular velocity of the rotating disk. Number of the vortex in the large-scale structure was also evaluated from the time-series p’ data. Time-space contour map was made for p’ based on the data measured at the different angular position, and showed periodical swept strip patterns. Presences of the strip patterns indicate the pressure disturbances were stably convected to the downstream. From this time-space map, two-dimensional Fourier transform efficiently extracted the number of vortices in the large-scale structure.
Keywords Rotating disk Flow stability Coherent structure Differential pressure measurement
Published Date 2017
Publication Title Transactions of the JSME
Volume volume83
Issue issue845
Publisher 日本機械学会
Start Page 16-00441
ISSN 00290270
NCID AN00187419
Content Type Journal Article
language 日本語
OAI-PMH Set 岡山大学
Copyright Holders © 2016 The Japan Society of Mechanical Engineers
File Version author
NAID 130005303917
DOI 10.1299/transjsme.16-00441
Related Url isVersionOf https://doi.org/10.1299/transjsme.16-00441
Title Alternative Periodical structure of vortices in a semiconductor single wafer spin cleaner
FullText URL TransJSME_81_829_2015.pdf
Author KOUCHI, Toshinori| FUKUDA, Naoya| NAKANO, Yusuke| SHIMIZU, Yoshiya| NAGATA, Yasunori| YANASE, Shinichiro|
Abstract We experimentally and numerically investigated large-scale structures formed by vortices in a single wafer spin cleaner. The Q-criterion identified the vortices developed in the cleaner as the flow regions with positive second invariant of the velocity gradient tensor obtained by both the PIV and LES. The time-series two-components PIV data shows that small-vortices were clustered near and under the edge of the rotating disk and were periodically emanated from there to the housing wall of the cleaner. The emanation frequency was increased with increasing in the angular velocity of the rotating disk. Three-dimensional LES reveal that six longitudinal vortices were spirally developed from under the edge of the rotating disk to the housing wall. This structure stably rotated slower than the disk speed. Fourier analysis of the LES data agreed with that of the PIV data. This supports that the passages of the stable spiral vortices on the PIV measurement region resulted in the periodical emanation of the clustered small-vortices observed in the PIV. Such a very large-scale spiral structure will induce reattachment of contaminants on the wafer surface, and should be destructed for development of much higher efficient cleaner.
Keywords Rotating disk Flow stability Large-scale structure PIV LES
Published Date 2015
Publication Title Transactions of the JSME
Volume volume81
Issue issue829
Publisher 日本機械学会
Start Page 15-00273
ISSN 00290270
NCID AN00187419
Content Type Journal Article
language 日本語
OAI-PMH Set 岡山大学
Copyright Holders © 2015 The Japan Society of Mechanical Engineers
File Version author
DOI 10.1299/transjsme.15-00273
Related Url isVersionOf https://doi.org/10.1299/transjsme.15-00273