Electrothermal Pumping With Thin Film Resistive Heaters

Rapid Electrokinetic Patterning (REP) is a technique used to gather suspended colloidal particles at a planar electrode surface. REP is capable of gathering colloids using very simplistic electrode geometry. Two parallel plate electrodes are used to supply an AC electric field, and an infrared laser is required to heat the surface. Gold and indium tin oxide (ITO) on glass slides have been used as electrode material. Experiments were conducted using ITO coated glass slides, a 980 nm infrared laser, one-micron red fluorescent polystyrene particles, and an aqueous KCl solution. An inverted Nikon Eclipse microscope was used, and video was captured using a PCO Sensicam camera.