Abstract: A composition composed of a persulfate, boric acid, a fluorine containing acid and an inorganic acid. Adjuvants also may be included in the composition. The composition may be employed as a microetch solution in the fabrication of microelectronic packages.

Abstract: A method is provided for electrodepositing a layer of copper on a plastic substrate which method comprises: positioning the plastic substrate on a supporting member, with the supporting member being in contact at a plurality of spaced apart points with the substrate for the passage of electrical current therebetween; electrolessly depositing a thin layer of metal selected from the group consisting of copper, nickel, cobalt and mixtures thereof on a surface of the plastic substrate; positioning the supported substrate in an electroplating bath including from about 10.0 to about 45.0 g/l of copper ions, at least one acid selected from the group consisting of sulfuric acid, fluoroboric acid and sulfamic acid, with the acid being present in an amount sufficient to cause the electroplating bath to have a conductivity ranging from about 0.40 to about 0.

Abstract: An aqueous acidic electroplating bath for the deposition of zinc is provided which comprises zinc ions in an amount sufficient to deposit zinc metal on a substrate, chloride ions in an amount sufficient to impart electrical conductivity to said bath, boric acid in an amount sufficient to buffer said bath to the desired pH, and an effective amount of at least one brightener selected from the group consisting of (i) condensation products of aromatic aldehydes with amides and (ii) condensation products of aromatic aldehydes with urea or substituted ureas.