Spatio-temporal structures of electrodeposited indium based alloys

Abstract

Ag-In, Pd-In and Co-In alloy coatings were electrodeposited under galvanostatic conditions from different solutions. The appearance and the composition of coatings were investigated by scanning electron microscopy (SEM) and energy-dispersive X-ray spectroscopy (EDS). The appearance of spatio-temporal structures on the surface of electrodeposited alloy layers is characteristic for all three indium containing alloys. Well-distinguished spirals were detected only at the surfaces of Ag-In and Co-In alloys, while for Pd-In alloy spatio-temporal structures are characterized with the valleys of different shapes surrounded by hills. In the case of Ag-In and Pd-In alloy coatings the cross-section does not show the presence of alloy layers with different composition, due to the fact that spatio-temporal structures are of large dimensions and cannot be seen on the high magnification images of the cross-sections. EDS line scan of the cross-section of Co-In alloy layers indicates the presence of layers with different compositions at high magnification, confirming that spatio-temporal structures are placed not only on the surface, but also in the bulk of the alloy coating.