Influence of substrate bias voltage on surface morphology and nanocluster arrangement of gold containing amorphous hydrogenated carbon

Abstract

Gold containing amorphous hydrogenated carbon (a-C:H/Au) thin films are studied by means of ex situ atomic-force and scanning electron microscopy, and in situ x-ray photoelectron spectroscopy. Introducing a dc substrate bias voltage during magnetron plasma-assisted chemical-vapor deposition of a-C:H/Au results in significant changes of surface morphology and nanocluster arrangement, compared to films deposited on electrically grounded substrates. Grounded samples are rather flat (below 1 nm of roughness), with topmost Au clusters covered with a very thin, nanometer-range layer of a-C:H. On the other hand, the biased sample surface is characterized by large bump structures (up to 13 nm in height) and bald gold clusters. © 2002 American Institute of Physics.