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Electrical Conductance Measurements of Fluidics

IR@CEERI: CSIR-Central Electronics Engineering Research Institute, Pilani


Field	Value

Title	Electrical Conductance Measurements of Fluidics

Creator	Soni, K Saini, RK Goyal, V Agarwal, A

Subject	MEMS and Microsensors

Description	In this work, DC conductance measurement techniques are analyzed which overcomes the limitations of several AC models, especially with respect to polarization, the parallel (Cp) and series (Cs) cell capacitances. Thesemeasurement analysis are done electrochemically on a silicon oxide micro gap structure with gold electrodes. Time domain potentiostatic methods namely voltage bias measurement, single pulse measurement and bipolar pulse method are carried out to accurately measure the response. The conductance of aqueous NaCl at concentration ranging from 0.1mM to 100mM was investigatedusing these methods. Conductance values as high as 11ns for 0.1mM, 20ns for 1mM, 23ns for 10mM and 29ns for 100mM concentrated aqueous solutions were measured. The Bipolar pulse method is more robust approach which is fast, accurate, wide ranged and independent of Cp and Cs as it overcomes some of the limitations of other DC techniques. In this method, consecutive equal magnitude but opposite polarity pulses of constant voltage are applied as input to the cell and the current/voltage ratio is measured at the end of the second pulse. The unwanted double layer impedance is reduced to a vanishingly small value due to small electrode polarization caused by the accumulation of ions on the surface of electrodes.

Date	2015

Type	Conference or Workshop Item PeerReviewed

Format	application/pdf

Identifier	http://ceeri.csircentral.net/263/1/12_2015%287%29.pdf Soni, K and Saini, RK and Goyal, V and Agarwal, A (2015) Electrical Conductance Measurements of Fluidics. In: Indo-UK Work Shop on Micro-Nano Fluidics for Health and Diagnostics (FluidicsHD-2015), August 27-28, 2015, CSIR-CEERI, Pilani. (Submitted)

Relation	http://ceeri.csircentral.net/263/