Ion and liquid dependent dielectric failure in electrowetting systems.

Detailed analysis of defect reduction in electrowetting dielectrics through a two-layer ‘barrier’ approach

a r t i c l e i n f o Low-voltage electrowetting requires a thin dielectric capacitor and field strengths approaching 1 MV/cm. Unlike traditional metal/dielectric/metal capacitors, the conducting electrowetted liquid can electrically propagate through the smallest dielectric defects or pores, even for the best barrier polymers such as Parylenes, leading to catastrophic failure such as electroly...

Reliable and low-voltage electrowetting on thin parylene films

a r t i c l e i n f o The stability of an electrowetting system is dependent upon the choice of liquids, the dielectric material and the operating voltage. Substantial progress is reported herein on use of 300 nm thick poly(α, α, α′, α′-tetrafluoro-para-xylylene) (Parylene HT) films for almost 100° of reliable electrowetting modulation at only 15 V. Not only does Parylene HT exhibit improved re...

Dielectric breakdown and failure of anodic aluminum oxide films for electrowetting systems

Shape Oscillation and Internal Mixing in Sessile Liquid Drops Using Electrowetting-on-Dielectric (EWOD)

Internal mixing within a sessile liquid drop can be significantly enhanced by means of so-called electrowetting-on-dielectric (EWOD), using an alternating electric potential. This is done experimentally by monitoring the coalescence and mixing of dyed liquid drops that are brought together by electrowetting actuation. The process is monitored using high-speed imaging and the extent of mixing wi...

Development of a Digital Micropump with Controlled Flow Rate for Microfluidic Platforms

This paper presents a novel device for pumping a column of liquid in a microchannel integrated on a digital microfluidic (DMF) platform. The electrowetting on dielectric (EWOD) method is used to frequently actuate a droplet (referred to as the piston droplet) on an array of electrodes. A column of liquid (referred to as the pumped droplet) is pumped in a microfluidic channel by the pressure com...