Papers by Keyword: Ammonia Mixture

Abstract: This paper summarizes the process development of TiN barrier etching in presence of copper, for a thick copper level in BICMOS technology. In an industrial context, we have chosen to use a SC1 chemistry in a spin etch single wafer tool. The SC1 composition and therefore the pH level allows - the barrier to be etched with no metallic residues, ( if not clear this can be a source for shorts) - control of the selectivity between copper and TiN - control of lateral etching under copper lines, the possible source of open chains by W attack during TiN etch. The electrical results show a robust process according to current specifications, in terms of leakage and via resistance with a fresh chemistry approach. In fact, the recirculation of SC1 is not possible due to substantial concentration changes during processing, high evaporation rate of Ammonia and high decomposition rate of Peroxide in the presence of copper on surface wafer.

Abstract: Ammonia generated from decomposition of a large amount of garbage, causes a serious environmental pollution. And also, carbon monoxide is notoriously a toxic compound and oxidized in the atmosphere to give carbon dioxide which causes green house effect or ozone depletion. We have investigated the possibility of carbonylation and amination, and proposed the reaction mechanisms for the photochemical transformation of carbon monoxide in aqueous methanol.