PHASE-BOUNDARY OF THE POLYIMIDE COPPER SYSTEM

The phase boundary in the system comprising a copper film deposited from solution onto a polyimide substrate was studied by X-ray photoelectron spectroscopy and electron microscopy. The boundary region represents a composite containing, in addition to metallic copper and polyimide, also Cu(I) and Cu(II) oxides, metallic Pd, PdO, oxo and hydroxo compounds of Sn(II) and Sn(IV), and a Cu-Pd alloy. This transition layer extends to a depth of not less than 20 nm from the interface into both polymer and copper films, the interphase and adhesion interactions are provided by the formation of Graphics and Graphics bonds and via the donor-acceptor mechanism with participation of nitrogen atoms from amido groups.