Adhesion improvement between Au films and glass by 1 keV Ar+ ion irradiation

Abstract

Au films with a thickness of around 1600 Å were deposited onto glass substrates at room temperature by an ion beam sputtering method, using a 5 cm cold hollow cathode ion gun at a pressure of 4–8×10−6 Torr. Irradiation of the Au/glass samples was carried out at pressure of 7×10−6 Torr. For the sputter deposition, the Ar+ ion energy was 1 keV and the current density at the surface of the substrate was 15 μA cm−2. Effects of 1 keV Ar+ ion doses (Id) ranging from 1×1016 to 2×1017 Ar+cm−2 on the properties such as crystallinity, surface roughness, and adhesion of the films have been investigated. Rutherford backscattering spectrometry showed that the thickness of Au films and sputtering yield were reduced by increase of Id and rms surface roughness of the films increased from 16 to 118 Å, as the ion dose was changed from 0 to 2×1017 Ar+ cm−2. Adhesion of Au films on the glass irradiated at Id=2×1017 Ar+ cm−2 was nine times greater than that of untreated Au films, as determined by a scratch test.