Influence of the autoirradiation on nanosized gold layers formation by the ion-beam deposition

Abstract

2–13 nm gold films were obtained by the method of ion-beam sputtering on silicon and quartz substrates. It is shown that the use of an additional operation of deposition followed by the sputtering of a gold layer of 2–3 nm thickness makes it possible to reduce the electrical resistance and surface roughness of the metal films, in comparison with similar films obtained without its use. The results of measuring the temperature coefficient of resistance of nanosized gold films on silicon substrates allowed us to conclude that the films deposited become continuous at a thickness of 6-8 nm. The results of optical measurements of 10 nm gold films, obtained on quartz substrates, showed that the reflection coefficient of electromagnetic radiation at a wavelength of 850 nm is 2.8 % higher than the corresponding coefficient for the same films obtained without using this operation, and is 83 %. An important role in the formation of nanoscale gold layers is played by the processes of self-irradiation of the growing layer of the high-energy component of the gold atoms flux. When using an additional operation of deposition/sputtering, high-energy gold atoms are implanted into the substrate to a depth of about 2 nm. On the one hand, these atoms are point defects in the surface damaged layer of the substrate; on the other hand, they serve as additional centers of cluster formation. This ensures strong adhesion of the metal layer to the substrate and, therefore, the gold films become continuous and more homogeneous in microstructure. The method of ion-beam deposition can be successfully applied to obtain high-quality conductive optically transparent nanosized gold films.