Patent ID: 9209147
Filing Date: 2015-12-08
Classification: B23K,H01L

Abstract:
1. A method of forming a pillar bump, the method comprising: feeding a bond wire in a capillary, the capillary having a hole portion and a chamfer section arranged downstream of the hole portion, the hole portion having a length along a feed direction of the bond wire that is greater than a maximum diameter of the hole portion; performing an electric flame off (EFO) on a free end of the bond wire extending from the chamfer section to form a free air ball (FAB); tensioning the bond wire and applying a vacuum to the capillary to withdraw a portion of the FAB back into the capillary to substantially fill the hole portion for forming a tower; attaching the FAB to a bonding site; and at least partially removing the capillary from the bonding site and breaking the bond wire above the tower.