A Failure Detection Technique for Au-Plated CMOS Microelectrode Arrays

A method for the detection of failure in gold-plated microelectrodes is presented. Three main failure mechanisms–layer detachment, biofouling and halide-mediated pas-sivation (HMP)–were induced on the microelectrodes, leading to electrode failure. Sequential admittance and sensitivity measurements were carried out on gold-plated microelectrodes on printed circuit boards (PCBs) and CMOS chips to develop and train the classifier. A two-step classifier is proposed that relies only on measuring the admittance magnitude (|Y|) at three specific frequencies within 0.6-800 Hz. The classifier achieves 88% accuracy on PCB microelectrodes and 92% accuracy on CMOS microelectrodes.