Light-Addressable Potentiometric Sensors - Model and Experiments

In the recent years reliable technologies for the production of ion-sensitive integrated devices compatible with conventional MOS technologies, have been developed. In this work, a numerical methodology suitable for device-level analysis of Light-Addressable Potentiometric Sensors (LAPS) is presented. The formulation of charge transport equations adopted in the present model accounts for the charge layers at the electrolyte-insulator interface and for AC-modulated optical generation rate, thus providing a self-consistent picture of charge and field distribution within the device. Comparisons with actual LAPS responses provide validation of the TCAD tool.