Temperature-dependent x-ray photoemission studies of metastable Co/polyimide interface formation

High‐resolution x‐ray photoelectron spectroscopy has been used to study the reactive Co/polyimide interface for temperatures 20≤T≤400 °C. Coverage‐dependent studies indicate vigorous but selective reaction for coverages below ∼5 A, followed by the evolution of a Co overlayer containing polymer fragments in solution. Stepwise heating of PI with a 40‐A Co overlayer enhanced reaction but also showed degradation of the reaction products. Annealing at 400 °C resulted in Co clustering on the surface and a decomposed Co/PI composite.