Electrochemical aspects of corrosion resistance and etching of metallizations for microelectronics

The electrochemical aspects of metal etching to form patterned conductors and of corrosion of conductors in the field are closely related. Both need to be considered in designing metallization structures for microelectronic devices. The evolution of a manufacturing process for a multi-level interconnect structure is discussed from an electrochemical perspective. A galvanic corrosion problem during manufacture and its solution for the interconnect metallization on a silicon integrated circuit are also discussed. Following the discussion on etching processes and corrosion during manufacture, a discussion of electrochemical and electrolytic failure mechanisms for electronic equipment in field environments and some steps that can be taken to prevent harmful environmental effects are presented. Recent research on the adhesion of various protective coatings and interlevel polymeric dielectrics is presented in the context of failure prevention.