Significance of inclusions in electroplated gold films for electronics applications

Abstract

Minute amounts of metallic as well as non-metallic inclusions significantly affect both bulk and surface properties of the electroplated gold films being used by the electronics industry. Surface effects are caused by the presence of extraneous materials diffused out from the interior to the surface, while bulk effects are brought about by the influence of inclusions on the microstructure of the gold films. This article reviews the current status of understanding of such inclusion effects in both soft and hard gold: these play essential roles in the fabrication of today's microelectronic devices.

Formulation and characterization of electrolyte for decorative gold plating based on mercaptotriazole

“…This electrolyte was originally proposed by Osaka and co-workers who used it to deposit soft gold, which was comparable to gold deposited from a sulphite electrolyte [18][19][20].…”

Electrodeposition of gold on tungsten nanowires present in NiAl–W eutectics

“…A clear proof on the nature of the latter ones could not be performed till now and will be the object of further studies in which these precipitates will be directly harvested by means of nano tweezers in a SEM. Further experiments should concentrate on the formation of smoother deposits by application of less negative overpotentials for the electrodeposition of Au(I) ions, or the use of alternative electrolyte solutions [22][23][24][25]. Due to the passivation of the matrix, only the wires and later the gold deposits remain electrochemically active which gives this approach an inherent advantage over an alternative route in which the gold electrodes are directly produced as the minor phase of a directionally transformed eutectoid system [26,27].…”

Development of new electrolytic and electroless gold plating processes for electronics applications

“…It is polycrystalline in microstructure with its grain size in the range of 20-30 nm, and its hardness is as high as 170-200 kg mm -2 in Knoop hardness compared to 50-80 kg mm -2 for pure, soft gold [15]. The detailed study of the hardening mechanism of the hard gold performed by Lo et al [16] shows that the major factor determining the hardness is the grain size.…”