Flow restrictor silicon membrane microvalve actuated by optically controlled paraffin phase transition

Kai Kolari (Corresponding Author), Tahvo Havia, Ingmar Stuns, K Hjort

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    4 Citations (Scopus)


    Restrictor valves allow proportional control of fluid flow but are rarely integrated in microfluidic systems. In this study, an optically actuated silicon membrane restrictor microvalve is demonstrated. Its actuation is based on the phase transition of paraffin, using a paraffin wax mixed with a suitable concentration of optically absorbing nanographite particles. Backing up the membrane with oil (the melted paraffin) allows for a compliant yet strong contact to the valve seat, which enables handling of high pressures. At flow rates up to 30 µL min-1 and at a pressure of 2 bars, the valve can successfully be closed and control the flow level by restriction. The use of this paraffin composite as an adhesive layer sandwiched between the silicon valve and glass eases fabrication. This type of restrictor valve is best suited for high pressure, low volume flow silicon-based nanofluidic systems
    Original languageEnglish
    Number of pages6
    JournalJournal of Micromechanics and Microengineering
    Issue number8
    Publication statusPublished - 2014
    MoE publication typeA1 Journal article-refereed



    • fluid dynamics
    • paraffin
    • wafer bonding
    • microfluidic systems

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