A CMOS Biocompatible Charge Detector for Biosensing Applications

A solid-state CMOS device capable of detecting the changes of electric charge caused by a chemical or biological reaction is presented. The device is fully compatible with a standard CMOS process. Biocompatibility is obtained by the passivation of the active area with a layer of alumina obtained with a simple, low-cost, and reliable process. A test chip hosting 80 sensors has been realized and characterized showing the detection capabilities of the novel sensor. The reusability of the device by stripping of the alumina layer was proved.