Enhanced plasma charging damage due to AC charging effect

Plasma charging damage from high density plasma (HDP) inter metal dielectrics (IMD) deposition process was found to be drastically enhanced as metal antenna is placed at higher interconnect layers. Such charging damage enhancement was ascribed to AC charging effect. By coupling with non-uniform plasma potential in HDP tools, the AC charging effect made important contributions to the final charging damages. A modified charge sharing model was used to interpret the dependence of AC charging damages on the location of metal antenna on interconnected layers.