A new approach for the direct synthesis of nanocomposite thin films by ion-beam processing

While energetic ion beams have been widely used to change the near-surface composition of thin films, the common practice is to rely on thermal annealing to control the distribution of chemical species in the processed layer. Our recent modeling and experimental work, however, establishes that ion-beam processing at a controlled temperature can also be used to tailor new microstructures with tunable length scales. In the case of a thin film made of immiscible elements, e.g. Cu and Ag, we show that ion-beam processing at intermediate temperatures (100–150°C) stabilizes nanocomposite structures. The relationship between processing conditions and microstructures is studied by X-ray diffraction (XRD), transmission electron microscopy (TEM) and scanning TEM, while the impact on hardness is followed by nanoindentation.