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There are three areas to consider when designing/implementing wire bonding to advanced ULSI damascene-copper chips having copper metallization and low dielectric-constant polymers embedded beneath them (Cu/LoK). These are: 1) the copper-pad top-surface oxidation inhibitor coating - metal/organic/inorganic. (Current work involves evaluating the metal and inorganic options); 2) the low dielectric constant materials available; 3) under-pad metal/polymer stacks and support structures necessary for bondability and reliability. There are also various polymer/metallurgical interactions, resulting in long term packaged-device reliability problems, that can occur as the result of the wire bonding process over low modulus, LoK materials with barriers. These include cracked diffusion barriers, copper diffusion into the LoK polymers, cracking/spalling/crazing of the LoK materials, and bond pad indentation ("cupping"). Low-K polymer materials, with high expansion coefficients and low thermal conductivities, can also increase the stress and further extend any existing damage to barriers. Well designed LoK and the underpad structures should have no negative effect on bonding parameters and be invisible to the bonding process.

This paper is the third published report on the results of a broad program on properties of electrodeposited copper, sponsored jointly by the American Electroplaters' Society, The International Copper Research Association, Inc., The Copper Development Association, and the National Bureau of Standards. The first paper is a comprehensive review of the literature to 1965. The second paper is an interim report on experimental results. The present and final paper, which incorporates the data in the second, includes data from the baths designated in the title, for deposits prepared under a wide range of operating conditions and with use of a variety of addition agents. Properties measured include tensile strength, yield strength, elongation, modulus of elasticity, fatigue strength, hardness, internal stress, density, electrical resistivity, and thermal expansivity. Properties were measured for as‐plated deposits, deposits after annealing at several temperatures, after cold‐working, and at low and high ambient temperatures. Structure of deposits was examined by optical, electron micrograph, and x‐ray methods. Content of impurities in deposits was determined. Correlations are developed among properties, structure, impurity content, type of bath, and operating conditions.