Articles from "Microelectronics News"

Fraunhofer Group for Microelectronics

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High-pressure micropump for demanding applications

 

Micropumps that can transport the tiniest volumes of liquids or gases are used in a wide range of applications. One area of use for these little helpers is in administering very precise dosages of medication, essential for example for treating tumors. In an industrial context, they regulate coolant circulation or ensure that machines are topped up precisely with lubricant. The delicate systems, however, are usually very sensitive to varying back pressures, particles, free flow, and air bubbles, all of which can affect the accuracy of the dosage result or result in the failure of the micropump.

 

Scientists at the Fraunhofer Research Institution for Modular Solid State Technologies EMFT have now developed an extremely small and powerful micropump made of silicon that is not affected by these factors. At only 7 x 7 x 1 mm³, the pump is no bigger than a sugar cube, yet can create pressures of up to 6 bar (liquids) or 1 bar (air and other compressible gases). An important “side effect” of this high compression ratio is that gas bubbles in fluids no longer present a problem to the mini-pump. With a cubic capacity of a mere 80 nl – about one five-hundredth of a drop of water – the pump allows extremely fine dosage of medication or lubricant. Thanks to its strong resistance to counterpressure, the cubic capacity is reduced by less than 1.5% at a counterpressure of 0.1 bar – making the pump almost independent of pressure in this low-pressure range. A special seal fitted directly at the pump chip functions as a safety valve. This valve can close even at high excess pressures and thus prevent free flow. A special filter has been integrated into the pump housing to catch occasional particles. Last but not least, the new highpower pump uses very little energy thanks to specially developed electronics.

Contact:

Dr. Martin Richter
Phone +49 89 54759-455
martin.richter(at)emft.fraunhofer.de
Fraunhofer Research Institution for Modular Solid State Technologies EMFT
Hansastraße 27 d
80686 Munich
Germany
www.emft.fraunhofer.de