Ion beam induced adhesion improvement of metal layers — a comparative study on composite layers

Abstract

The adhesion of thin layers of metals like Al, Cu, Cr, Ti etc. on polymer, ceramic or composite substrates is of great importance for microelectronics (printed circuits, packaging), and materials science. Therefore investigations on the adhesion improvement of copper on high temperature thermoplasts, carbon fibre reinforced polymers (CFK) and pure carbon by ion bombardment were undertaken. Ion beam mixing as well as ion beam assisted deposition (IBAD) was applied. It was shown that the electronic stopping power is the most important parameter for adhesion in the case of ion beam mixing by non-reactive ions. Reactive ions, especially metals, add an important chemical effect when stopped near the interface. IBAD Cu-layers have only good adhesion properties when prepared by low energy ion bombardment or with reactive intermediate layers.