Surface analysis of adsorbed species from epoxy adhesives used in microelectronics

Experiments were conducted to investigate adsorbed species that originated from two epoxy adhesives that are used for die (chip) and substrate attachment in hybrid microcircuits. Evaporated aluminum on silicon substrates were cleaned with ultraviolet/ozone prior to the exposure to epoxies during cure and post-cure. Adsorbed carbon and, in some cases, nitrogen species were observed in the Auger electron spectra. No other elements were detected that could definitely be associated with the epoxies. The results suggest that surface diffusion may play a major role in the transport of species that originate from adhesives. No unusual species were observed when both epoxies were present together.