Ion-induced deposition is a process of film growth where adsorbed gas (usually organometallic) molecules are decomposed on the surface by ion impact leaving a deposit behind. This process is used in focused ion beam repair of microelectronic devices and masks. The deposited films are usually mixtures of metal and carbon. We have studied the microstructure of ion deposited gold by transmission electron microscopy. The gas used was dimethylgold hexafluoroacetylacetonate. The film is found to be made up of segregated gold and carbon. The gold can either be in the form of grains (isolated, approximately spherical islands 20-50 nm in diameter), in the form of columns of comparable diameter perpendicular to the surface, or in the form of a normal polycrystalline structure. Higher temperature growth (80-100 degrees C) or slower growth rate favors the polycrystalline films, while faster growth or growth at room temperature tends to produce granular films with a high carbon content. The incorporation of carbon may be related to the inability of the reaction products to escape from the surface.