The Nucleation, Growth, and Structure of Electroless Copper Deposits

Abstract

An electron microscopic investigation has revealed that the electroless deposition of copper occurs by repeated three‐dimensional nucleation at catalytic sites on a substrate. The nature of the catalytic sites formed by immersion in the standard stannous and palladium chloride solutions was observed and found to influence the structure of the subsequently deposited metal. Initially, copper nuclei about 25Aå in diameter form aggregates an order of magnitude larger. As the autocatalytic reduction reaction continues the aggregates increase in size until they become energetically unstable; then recrystallization occurs. The resulting continuous copper films exhibit a heterogeneous microstructure with grain size variations of more than an order of magnitude and also numerous twin faults.

CoNiP Perpendicular Magnetic Recording Medium Electroless-Deposited from Single-Complextant Bath at Room-Temperature

“…However, each grain develops a uneven condition at their surface, suggesting that they consist of further smaller particles. These results corresponds to those of electroless NiP films obtained previously, suggesting that the film growth process is considered to be due to the successive nucleation of the grains and their three-dimensional growth [13][14][15].…”

Microstructure evolution during electroless copper deposition

“…Both papers concern only the early stages of copper deposition. Sard [13] proposed a three-stage development of the copper film; repeated three-dimensional nucleation at catalytic sites, followed by affiregation of the copper nuclei into particles an order of magnitude larger, and finally, recrystallization. Rantell [14] favored a dynamic coalescence model; initially deposited copper islands are mobile and coalesce as they grow larger.…”

Preparation of Conductive Particles by Electroless Nickel Plating on Polystyrene Microsphere

“…Its common procedure is: first the surface of the polymer is "sensitized" by attachment of Sn2+ nuclei, and then "activated" by further replacement of Pd2+ nuclei. [9][10][11][12] The final electroless plating is carried Sn 2 l sensitize out in a plating bath under the strict control of composition, pH and temperature. In this article, to prepare the conductive particles used in anisotropic conductive adhesive, electroless nickel plating on the polystyrene microspheres was studied.…”