Non Contact Surface Potential Measurements for Charging Reduction During Manufacturing of Metal-Insulator-Metal Capacitors

摘要

In this paper, charging induced damage (CID) to metal-insulator-metal-capacitor (MIMC), is reported. The damage is caused by the build up of charges on an oxide surface during a water rinsing step. The excessive charging over a large capacitor area results in a discharge over the inter metal dielectric layer (IMD) towards a grounded structure. This CID leads to direct severe yield loss. The charging has been detected, measured and reduced with the help of a non contact surface potential measurement. In this way further yield losses have been Prevented. A model for the relation between the surface charging potential and the voltage difference between the capacitor and the grounded structure is presented.