Plasma damage evaluation of an integrated in-situ directional resist stripping process in magnetically enhanced RIE etcher for dual damascene application

This paper demonstrates the plasma induced device damage performance of a directional resist removal process for Cu/low-k dielectric dual damascene interconnect integration application. A Magnetically Enhanced Reactive Ion Etching (MERIE) chamber running oxygen based plasma is used for this study with a clean chamber mode. Parameters including power, pressure, overetch and gas species are investigated on the plasma induced charging damage of 0.25 /spl mu/m technology devices. It is found that power is the most sensitive parameter than B-field, pressure, overetch and gas species to control damage. A contact bottom polymer/etch stop nitride shielding mechanism is proposed to explain the plasma damage sensitivity in oxygen plasma environment.