Design strategies for multielectrode arrays applicable for high-throughput impedance spectroscopy on novel gas sensor materials

This paper reports the first design and fabrication of a 64 multielectrode array for high-throughput impedance spectroscopy. The purpose of this work is the development of a measurement system for the discovery and improvement of sensor materials using combinatorial methods. An array of interdigital capacitors (IDC) screen-printed onto a high-temperature-resistant Al2O3 substrate is determined to be the optimal test plate. The electrode layout, and therefore also the idle capacity, is determined by specific requirements. Calculation of the idle capacity of the IDC as a function of the electrode width and distance allows adjustment and thus optimization of the array. Parasitic effects caused by the leads and contacts are compensated by a software-aided calibration. Apart from the use of the substrates for discovery of new sensor materials, the presented electrode array is also suitable for electrocatalytic applications as well as impedance spectroscopic studies of semiconductors and dielectrics.