Laser-induced Ejection of a Millimeter-sized Liquid Droplet from a Metal Surface by IR Laser Irradiation at Three Different Pulse Durations

Laser-induced cleaning by the elimination of liquid contaminant droplets from the surface of a solid substrate is an attractive application of laser technology. We report the laser-induced ejection of an organic carbonate liquid droplet from an aluminum surface using three different infrared (IR) laser pulse durations (5.7 ns, 35 ns, and 90 μs). Single-shot cleaning of a large area sample through a noncontact process was achieved by irradiation with a nanosecond-pulsed laser. The dynamic behavior of liquid desorption was observed with a high-speed CCD camera. The threshold laser fluences for liquid desorption by laser irradiations were determined for each of the lasers. The laser pulse duration increased with increasing threshold laser fluence.