Engineering change (EC) technology for thin film metallurgy on polyimide films

Engineering change in multichip modules such as the IBM Thermal Conduction Module (TCM) requires making new nets on the top surface of the module. This is done either to repair opens or shorts in the internal nets or to correct design errors. Since the trend in multichip packaging in the high end is towards thin-film wiring with polyimide as the dielectric, wire-bond and laser delete processes compatible with thin-film metallurgy on polyimide films are required to carry out engineering change. The authors describe the results of a technology-development effort to optimize these processes on a metal/polyimide thin-film structure.<
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