Microstructure of Gold Films Grown by Ion Induced Deposition

A beam of ions incident on a substrate can cause adsorbed gas molecules to break up, resulting in material deposition. We have previously demonstrated deposition of gold from a gas of dimethyl gold hexafluoro acetylacetonate (C 7 H 7 F 6 O 2 Au) using both focused and broad ion beams. Here we investigate growth at various substrate temperatures and examine micro-structure using transmission electron microscopy. Films grown at room temperature were discontinuous even up to the thickness of 250μπι while films grown at higher substrate temperatures were continuous even at lower thicknesses. Deposition carried out on substrates at 100°C and 160°C using 70 kev Ar + ions resulted in resistivities approaching the bulk value and a deposition yield of 60 to 75 atoms/ion. The relationship between growth conditions, micro-structure and resistivity will be discussed.