Molecular design for inhibition of titanium corrosion in resist cleaner systems

A range of substituted catechols and pyrogallols are examined as corrosion inhibitors for titanium during processing with resist cleaners in the micro electronic industry, The corrosion inhibition is consistent with an adsorpt ion mechanism and the best predictor for inhibition performance is found to be the hydrophobicity of the molecule. The trihydroxybenzenes adsorb more strongly on the titanium surface than the corresponding dihydroxybenzene co mpounds, It is also shown that trace quantities of calcium act as an extremely effec tive inhibitor. Consequently, calcium levels in the organic material must b e reduced to less than approximate to2 ppm before measurement of the inhibi tion efficiency. (C) 2001 Elsevier Science Ltd. All rights reserved.