Investigation of Dissolution and Electrodeposition of Copper in Concentrated and Diluted Oxalic Acid Media in Post-CMP Cleaning.
Abstract
In the microelectronic industry using the damascene process, dendritic growth is observed on some parts of the circuits in critical conditions during the post-CMP cleaning step. To understand the electrochemical mechanism leading to this parasitic phenomenon copper behaviour in oxalic acid media was investigated by impedance measurement in both cathodic and anodic potential range and the dendritic growth conditions were studied.. Copper-oxalate complexes in the solution are taken into account.