Electroless copper plating
AssigneeShipley Company, L.L.C.
InventorsMagda Abu-Moustafa, Silvester P. Valayil
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Abstract
An electroless copper plating solution containing, in aqueous medium, cupric ions, hydroxyl radicals, complexing agent for cupric ions, formaldehyde and a formaldehyde addition agent; wherein the molar ratio of each of copper and free formaldehyde to hydroxyl radical is between 1 to 10 and 1 to 40.
Claims9
An electroless copper plating solution comprising dissolved copper, hydroxide, sufficient complexing agent for the dissolved copper to render the same soluble in alkaline solution and an adduct comprising the reaction product of formaldehyde and a formaldehyde addition agent, said solution having a pH of at least 11 and a molar ratio of each of copper and free formaldehyde to hydroxide varying between 1 to 10 and 1 to 40.
A process for initiating plating from a freshly prepared electroless copper plating solution comprising a source of dissolved copper, hydroxide, complexing agent for the dissolved copper in an amount sufficient to render the same soluble in alkaline solution and an adduct comprising the reaction product of formaldehyde and a formaldehyde addition agent, said solution having a pH of at least 11 and a molar ratio of each of copper and free formaldehyde to hydroxide varying between 1 to 10 and 1 to 40, said process comprising adding free formaldehyde to the solution in an amount sufficient to initiate deposition.
Dependencies are inferred from the claim text.