Method and apparatus to detect nanometer particles in ultra pure liquids using acoustic microcavitation

摘要

An apparatus to produce acoustic cavitation by controlling cavitation events in a liquid insonification medium utilizing a waveform to excite a transducer with a series of bipolar inharmonic tone bursts having medium recovery intervals between respective bursts so that the medium repeatedly recovers from cavitation events between bursts. The apparatus may be used to clean a semiconductor wafer, to de-coat a painted surface having, to induce a chemical reaction, and/or to provide recycled paper made from inked paper de-inked by cavitation. Cavitation events are generated using a transducer and a waveform generator, e.g., square wave tone bursts, to excite the transducer with a signal controlled in frequency, burst repetition rate, duty-cycle and/or amplitude, e.g., utilizing bursts having a frequency between 500 KHz and 10 MHz, and a duty cycle between 0.1% and 70%.