| 摘要 |
PROBLEM TO BE SOLVED: To obtain a method for cleaning the silver plated surface of a lead frame capable of surely improving the degraded wettability with solder and wire bondability of the silver plated surface when the gases, etc., generated at the time of sticking an org. film to the lead frame, etc., stick to the silver plated surface and the wettability with solder and wire bondability thereof are degraded. SOLUTION: The silver plated surface of the lead frame, etc., is irradiated with electron beams, by which the org. materials sticking to the plated surface are changed in properties and are removed and, simultaneously, the silver oxide on the plated surface is reduced, by which the cleaned silver plated surface is formed. The lead frame 3 is sent from a vacuum preliminary chamber 4 to a vacuum processing chamber 5 and is supplied above a supplementary heater 6, by which the silver plated surface of the lead frame 3 is heated to a prescribed temp. The plated surface is then irradiated with the electron beams from an electron source 1. |
