Thermally driven microvalve with buckling behaviour for pneumatic applications

The paper presents theoretical and experimental results of a new thermally driven microvalve. In contrast to earlier reported devices with bimorph composition this valve is based on the buckling effect of a heated pure silicon bridge structure. Simulation, fabrication and experimental results are presented. Analytical and finite-element calculations of the thermomechanical behaviour are performed. Prototypes of this first valve design operate with inlet pressures up to 1.0 bar showing flow rates of more than 700 ml/min. The measured switching time is about 15 ms which is extremely low for thermal principles. The power consumption of this valve is between 1 and 4 W.

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