METHODS AND APPARATUS FOR CLEANING SEMICONDUCTOR WAFERS

摘要

A method for cleaning semiconductor substrate without damaging patterned structure on the substrate using ultra/mega sonic device comprising applying liquid into a space between a substrate and an ultra/mega sonic device； setting an ultra/mega sonic power supply at frequency f1 and power P1 to drive said ultra/mega sonic device； before bubble cavitation in said liquid damaging patterned structure on the substrate, setting said ultra/mega sonic power supply at frequency f2 and power P2 to drive said ultra/mega sonic device； after temperature inside bubble cooling down to a set temperature, setting said ultra/mega sonic power supply at frequency f1 and power P1 again； repeating above steps till the substrate being cleaned. Normally, if f1＝f2, then P2 is equal to zero or much less than P1； if P1＝P2, then f2 is higher than f1； if the f1