Morphology Evolution of Nanoscale-Thick Au/Pd Bimetallic Films on Silicon Carbide Substrate

Abstract

Bimetallic Au/Pd nanoscale-thick films were sputter-deposited at room temperature on a silicon carbide (SiC) surface, and the surface-morphology evolution of the films versus thickness was studied with scanning electron microscopy. This study allowed to elucidate the Au/Pd growth mechanism by identifying characteristic growth regimes, and to quantify the characteristic parameters of the growth process. In particular, we observed that the Au/Pd film initially grew as three-dimensional clusters; then, increasing Au/Pd film thickness, film morphology evolved from isolated clusters to partially coalesced wormlike structures, followed by percolation morphology, and, finally, into a continuous rough film. The application of the interrupted coalescence model allowed us to evaluate a critical mean cluster diameter for partial coalescence, and the application of Vincent’s model allowed us to quantify the critical Au/Pd coverage for percolation transition.

Editorial for the Special Issue on 2D Nanomaterials Processing and Integration in Miniaturized Devices

“…Such a plethora of material/application combinations, in addition to the obvious technical requirements related to the synthesis of materials and the optimization of purity, composition, morphology and yield, also presents significant technological challenges for the corresponding processing, patterning and above all integration into systems and devices of higher dimensionality for the real exploitation of their unique properties. The present Special Issue is then focused on such last topics, collecting eight research papers and one review article dealing with MoS 2 [ 1 ], graphene [ 2 , 3 , 4 ] and other 2D nanomaterials integrated onto several kinds of materials and structures (nanogap [ 1 ], porous silicon [ 5 ], silicon carbide [ 6 ]) and for different applications (photoluminescence [ 1 ], ink-jet printing [ 7 ], optics and plasmonics [ 2 , 8 ], lubrication [ 3 ], innovative patterning [ 4 ], biomedicine [ 9 ]).…”

“…A thorough characterization was performed, providing valuable data for the control of porous silicon thickness and porosity. Ruffino et al [ 6 ] provided a valuable basic study on the growth and coalescence characteristics of a nanoscale-thick bimetallic film of Au/Pd on a silicon carbide substrate. The kinetic of the growth process was studied from the initial 3D clustering to the final continuous rough thin film formation.…”