A novel miniaturized travelling wave dielectrophoresis microseparator for lab-on-a-chip applications

Particle separation is a challenge by highly miniaturized channel systems. Due to very low Reynolds number of buffer fluid, microseparators based on travelling wave dielectrophoresis effect have a good sufficiency in such applications. In this paper a microchannel technique based on surface micromachining is modified to a microseparator. Due to fabrication process the electrodes made of highly doped polysilicon are covered by a thin silicon-nitride layer. The influence of this thin isolating layer on functionality of the microseparator is investigated. The simulation results indicate that a satisfied separation occurs in the frequency range of 1MHz, when electrical conductivity of buffer fluid is lower than 1μs/m. The fabrication process is presented and influences of other parameters such as permittivity of fluid and bias voltage on the operation of separator are discussed.