Authors: J. Berthier, O. Raccurt, Ph. Clementz, D. Jary, P. Claustre, C. Peponnet and Y. Fouillet
Affilation: CEA-LETI, France
Pages: 664 - 667
Keywords: digital microfluidics, EWOD, drop extraction
In the preceding text submitted to Nanotech 2005, we have demonstrated that surface tension is the dominant force on liquid microdrops in EWOD microsystems and that the problem is mostly topological. Minimization of the surface energy submitted to Young constraints gives very satisfactory results. In this paper, by using Young and Laplace laws, we produce an analytical implicit equation to describe the splitting of drops. The results compare favourably with the results of the Surface Evolver software and with experimental results. Using the splitting equation, we find the limit vertical gap above which extraction is not possible, we show that the value of the surface tension is not very important and we evaluate the influence of the dimensions of the cutting electrode.