Explosive vaporization and microbubble oscillations on submicron width thin film strip heaters

Boiling induced by an electrically heated submicron strip platinum heater submerged in deionized water is investigated in this work. The temperature evolution of the heater subjected to pulsed heating showed a fast transient behavior followed by a temperature plateau. The boiling initiation temperatures for a host of current intensities were determined and an interesting consistent oscillation in the temperature curve in the plateau region was discovered and analyzed. This oscillation was shown to originate from sequential bubble growth and collapse cycles taking place at a high frequency (MHz). Visualization of the process confirmed the formation of vapor bubbles of ca. 1 μm diameter on the heater.