Substrate cleaning using ultrasonics/megasonics

The adhesion and detachment forces acting on spherical particles attached to a substrate is investigated. It is found that alumina particles larger than 50 nm and glass particles larger than 10 nm can be successfully dislodged by acoustic waves in an ultrasonic tank. Inspection of detachment forces reveals that the dominant detachment force is acoustic cavitation force for particles larger than 35 nm (f = 950 kHz).