Ion Beam Enhanced Adhesion of Thin Films

Abstract

ABSTRACTIon beam enhanced adhesion has been studied for the case of thin Cu films deposited on substrates of alumina, fused quartz and glass-ceramic. Beams of He+ (200 keV) and Ne+ (280 keV) were used, in order to test the respective roles of nuclear and electronic interactions in this process. Peel tests were used to produce the first quantitative studies of adhesion strength as a continuous function of ion dose. Bond strengths improved after irradiation at modest doses, sometimes by a factor of 20. Subsequent heating in a helium furnace produced as much as an order of magnitude further adhesion improvement in irradiated samples. Similar tests for Cu on Teflon produced excellent bonding for ion doses of ∼ 1014/cm2. The results indicate bond breaking and reconstruction at a sharp interface, with no significant metalsubstrate intermixing. The new bond is stable under heat cycling.