A transducer for use in an acoustic energy cleaner is provided. The transducer includes a resonator and a plurality of crystals bonded to a surface of the resonator. The plurality of crystals is configured to be bonded to the surface of the resonator in a staggered arrangement with respect to each other....http://www.google.com.tw/patents/US7237564?utm_source=gb-gplus-share專利 US7237564 - Distribution of energy in a high frequency resonating wafer processing system
