Detection of large-scale vortices in a semiconductor wafer cleaner by using microphone

Abstract

In semiconductor production, efficiency and precision of the cleaning process is important. In this study, we handle “Single Wafer Cleaner” that is one of the washing methods in the way of blowing air to a wafer with a turning disk at a high speed. However, the flow in the device becomes turbulence, which causes a problem that water drops and dusts re-attach to the wafer. It is necessary to understand the flow in the device. In previous investigations, we were able to get knowledge of the detection of vortices using numerical computation and Particle Image Velocimetry analysis in using the simplified experiment model. Therefore, we tried to understand the detection of large-scale vortices combining speed data and the unsteady pressure data. We measure pressure using microphones and perform the frequency analysis and cross correlation of the data. In doing so, we have get the knowledge of the vortical structure.