Study Of Electrowetting Based On Low Surface Energy Material

Display technology is one of the important technical developments in recent years. It has experimented Cathode Ray Tube to Liquid Crystal Display and Plasma Display Panel. Although the existing display technologies have made great breakthroughs in the size and power consumption, it is hoped that further development of display technology.Electrowetting is defined as the change in solid electrolyte contact angle due to an applied potential difference between the solid and the electrolyte. Displays based on Electrowetting have a low-power, a video-rate response time, rich colors and other characteristics. Electrowetting displays are generally considered to be one of the main display technologies for the future. Applications of electrowetting are not only displays but also lab-on-a-chip and MEMS devices. It attracted many researchers in recent years. The paper has done the following research work in electrowetting with advantage of spinning and spin-coating methods in laboratory:1 Built a platform of electrowetting measurement. Contact angle and voltage can be measured synchronously in the platform. The hydrophobicity and electrowetting measurements of the paper were based on the platform.2 PTFE films were prepared by spinning and spin-coating respectively. The hydrophobicities of films were observed. The impact of rotate speed and temperature on wetting were Analyzed. It was found that the film became hydrophobic when rotate speed was up to 3000rpm and temperature was above 180℃according to adjust experiment parameters. The films prepared by spinning were hydrophilic. Their structure was very loosening and grains haven't separated.3 Electrowetting sample based on different dielectric layer were prepared. Barium titanate and titanium dioxide were used as dielectric layer of electrowetting. Barium titanate was deposited by PLD and titanium dioxide was deposited by Sol-Gel method. The electrowetting samples with different dielectric were prepared after PTFE film was spin-coated on the dielectric layer.4 Analyzed the influence of friction between hydrophobic materials and liquid in electrowetting. Concluded the condition of contact angle change is that the applied voltage is greater than the critical voltage. The critical voltage is decided by dielectric constant, thickness and friction factor. The contact angle would not change until the voltage is greater than the critical voltage. There would be mutation because of friction. The mutation were Observed in all samples. The measurement also showed that the critical voltage of samples based on barium titanate is lower than samples based on titanium dioxide.5 NaCl solution and CuSO₄ solution were used as electrolyte in electrowetting respectively. Electrolysis was observed in electrowetting when the solution is CuSO₄. It was found that electrolyte with lower electrolysis voltage would be prone to electrolysis in experiment.