Direct observation of inclusions in cobalt-hardened gold electrodeposits.
01 January 1989
A transmission electron microscope was used to study inclusions in cobalt-hardened gold electrodeposits. The fine(~350angstroms)- grained deposits contain a high (~5 x 10 sup (17) /cm sup 3) density of small (~25angstrom) inclusions. During dissolution of the deposit in aqua regia, these inclusions agglomerate on the gold film surface and finally form a "polymer" film. From an electron diffraction analysis, the "polymer" film was found to contain both amorphous and crystalline phases. The crystalline phase was identified to be a cobalt-cyanide complex, the structure of which agrees with previous x-ray results. In addition to the cobalt-cyanide complex, we discovered the inclusions of AuCN crystals.