| 摘要 |
PURPOSE:To prevent improper plating due to adherence of air bubbles in electrically plating step from occurring and to stably form a bump of desired shape by interrupting a plating operation on the way of electrically plating, and physically isolating a part to be plated from plating solution. CONSTITUTION:When a conductive film of a 3-layer structure is gold-plated and electrically plating is interrupted due to the OFF of a DC power source, gold plating solution 2 in a plating vessel 3 is returned through a pipe 8 to a storage tank 1 owing to the stop of a pump 9, the gold plating solution 2 in the vessel 3 drops to a level L, the solution 2 is momentarily isolated from the conductive film exposed from the opening 18 of a dry film 17 of a wafer 11 mounted on a holding member 6 at the top of the vessel 3, and air bubbles adhered to the opening 18 or the like are removed. Thus, the interruption of the plating operation, and isolation of the solution from the conductive film of the wafer 11 are conducted for 30 sec at each plating time, and these steps are executed, totally 7 times, and a gold bump 19 of substantially the same thickness as that of the film 17 is selectively formed on the exposed conductive film from each opening 18. |
