A GALVANIC SERIES FOR THIN-FILM METALLIZATIONS AND BARRIER LAYERS COMMONLY USED IN THE MICROELECTRONICS INDUSTRY

A galvanic series was developed for a variety of thin-film metallizations and barrier layers deposited on oxidized Si substrates. The series was determined by listing the stable open-circuit potentials of thin-film metallizations, barrier layers, and metal/barrier-layer couples that were evaluated using a 2000 ppm NH4Cl electrolyte. The findings are particularly meaningful for the manufacture of microelectronic devices, because the relative corrosion tendencies of microelectronic materials have been determined traditionally from galvanic tables based on their bulk counterparts in seawater. Moreover, the Cl- concentrations of the aqueous electrolytes used in these bulk evaluations have often been higher than those frequently encountered in standard immersion, environmental, and accelerated stress tests.