Monitoring of cavitation threshold under megasonic agitation

Abstract

In the traditional cleaning techniques, the semiconductors industry has always used the chemical process for cleaning the substrate after implanting or etching. But in the case of modern technologies, this process is no longer used. Instead, the chemical action is being combined with physical forces, thereby leading to more interesting results. The present paper highlights some indicators in signal processing to measure the cavitation created with the combination of chemical and applied megasonic energy. The finding can establish a better correlation between megasonic cleaning and threshold cavitation in order not to damage sensitive semiconductors devices. Furthermore, the signal processing of each combination can control process cleaning (safe or higher cavitation) by developing a new generation of sensors. This research aims to provide some parameters in order to quantify cavitation by controlling electrical power transferred to piezo electric transducers, and to identify the spectral map for each solvent reaction from stable to transient cavitation measured by the hydrophone and analysed by Matlab and Labview code.The novelty of this study is providing some parameters such as Fast Fourier Transform (FFT), Total Harmonic Distortion (THD) and Fundamental Pick Distortion (FPD) to quantify a hybrid technic megasonic/chemicals solvent to control threshold cavitation for achieving a safe cleaning and damage-free.