METHOD FOR REPLENISHING Sn-ALLOY PLATING SOLUTION WITH Sn-COMPONENT AND Sn-ALLOY PLATING TREATMENT APPARATUS

摘要

PROBLEM TO BE SOLVED: To provide a method by which Sn-alloy plating solution is replenished with Sn-component at a low cost; and to provide a Sn-alloy plating treatment apparatus which is used in the method and can suppress the occurrence of sludge in the plating solution.;SOLUTION: A method for replenishing a plating solution 21 of a Sn-alloy composed of Sn and an element nobler than Sn with divalent Sn ion, is characterized in that a stannous oxide powder easily soluble in an acid or an acidic plating solution is directly added to the plating solution. When the Sn-component is resupplied, the special Sn-alloy plating treatment apparatus 20 is used, and electroplating is carried out while controlling the flow rate of an inert gas being blown into the plating solution in response to the measured value by a dissolved oxygen densitometer 41 for measuring the concentration of dissolved oxygen in the Sn-alloy plating solution 21. It is preferable that the average particle diameter of the stannous oxide powder is in a range of 10-20 μm as expressed by D₅₀ value, and the tapping density of the powder is 0.6-1.2 g/cm³.;COPYRIGHT: (C)2009,JPO&INPIT