Upon use of an immersion tin plating solution, contaminants build in the solution, which cause the plating rate and the quality of the plated deposit to decrease. One primary contaminant, which builds in the plating solution upon use, is hydrogen sulfide, H.sub.2S. If a gas is bubbled or blown through the solution, contaminants, especially hydrogen sulfide, can be effectively removed from the solution and, as a result, the high plating rate and plate quality can be restored or maintained. In this regard, any gas can be used, however, it is preferable to use a gas that will not detrimentally interact with the solution, other than to strip out contaminants. Nitrogen is particularly preferred for this purpose because it is efficient at stripping out contaminants, including hydrogen sulfide, but does not induce the oxidation of the tin ions from their divalent state to the tetravalent state, which is detrimental.

The present invention is directed to compositions for electroless plating baths and their use, and more particularly to different solutions each usable to both make up an original bath and to replenishment of the original bath.

The present invention is directed to compositions for electroless plating baths and their use, and more particularly to different solutions or concentrates each usable to both make up an original bath and to replenishment of the original bath.

Methods of refreshing plating solutions containing phosphate anions, refreshed plating solutions, and uses thereof are described. The method may include adding a metal sulfate to the plating solution; precipitating out phosphate anions present in the plating solution with metal ions from the metal sulfate; adding barium carbonate to the plating solution; precipitating sulfate introduced from the metal sulfate added to the plating solution with barium from the barium carbonate; separating insoluble components from the plating solution; and replenishing the plating solution with components originally present in the plating solution.

The invention relates to a depositing station comprising a basin arrangement (11) having a basin (13) forming a processing chamber (12) and serving to receive a solution of a metal, in particular nickel, zinc, palladium, gold or the like, dissolved in a liquid, for a, preferably electroless, deposition on an object receivable in the processing chamber, in particular on a terminal face of a wafer receivable in the processing chamber, the basin having at least one inlet (17) for introducing the solution into the basin, the basin having a perforation (18) which forms at least part of the inlet of the basin and which is configured to homogeneously introduce the solution into the processing chamber. Furthermore, the invention relates to a device for producing contact metallizations on terminal faces of wafers, comprising at least one depositing station.

Systems and methods for nickel plating include providing a tank that retains a plating bath into which a substrate is submerged, and creating a horizontal flow of processing solution in the plating bath to assist in carrying contaminants out of the plating bath. A sparger box may be positioned in the tank to deliver the processing solution into the plating bath in a horizontal direction. The processing solution, which carries the contaminants, may exit the plating bath through a plate member that includes a plurality of orifices and is also positioned in the tank. The orifices may have a variable opening size to help control outflow of the processing solution.

A method for removing soluble ferrous iron from a galvanizing flux solution includes circulating the flux solution through a concentration loop and injecting ozone into the concentration loop, wherein the ozone mixes with the flux solution and reacts with soluble ferrous iron to form insoluble ferric iron in the loop. Flux solution that is substantially free of insoluble ferric iron may be removed from the concentration loop through a filter medium such as a cross-flow microfilter, thereby concentrating the ferric iron in the concentration loop. The ozone may be injected through an eductor that utilizes motive force from a circulation pump, thereby reducing energy consumption and providing rapid mixing and reaction of ozone and ferrous iron.

A method for removing soluble ferrous iron from a galvanizing flux solution includes circulating the flux solution through a concentration loop and injecting ozone into the concentration loop, wherein the ozone mixes with the flux solution and reacts with soluble ferrous iron to form insoluble ferric iron in the loop. Flux solution that is substantially free of insoluble ferric iron may be removed from the concentration loop through a filter medium such as a cross-flow microfilter, thereby concentrating the ferric iron in the concentration loop. The ozone may be injected through an eductor that utilizes motive force from a circulation pump, thereby reducing energy consumption and providing rapid mixing and reaction of ozone and ferrous iron.

A plating solution for electroless plating is disclosed, the solution including a metal salt, a reducing agent, a complexing agent, and a dispersion including polytetrafluoroethylene (PTFE) particulate matter and at least one particulate matter stabilizer, where said dispersion includes 400 parts per million or less of perfluorooctanoic acid (PFOA), and said dispersion is usable for an electroless plating bath to form a coating including PTFE particulate matter on an article.

The method of producing stannous oxide includes: a Sn ion-containing acid solution forming step (S01); a first neutralizing step (S02), which is a step of forming Sn precipitates by adding one or more of alkaline solutions of ammonium carbonate, ammonium bicarbonate, and aqueous ammonia to the Sn ion-containing acid solution to retain pH at 3-6 therein; a Sn precipitate separating step (S03); a Sn precipitate dispersing step (S04), which is a step of dispersing the separated Sn precipitates in a solvent liquid to obtain a dispersion liquid; and a second neutralizing step (S06), which is a step of forming SnO by adding an alkaline solution to the dispersion liquid of the Sn precipitates and then by heating, wherein Na, K, Pb, Fe, Ni, Cu, Zn, Al, Mg, Ca, Cr, Mn, Co, In, and Cd reside in the Sn ion-containing acid solution in the first neutralizing step (S02).