Method of forming pillar bump
US9209147B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Jul 17, 2014 |
| Grant date | Dec 8, 2015 |
| Priority date | — |
| Expiry date | Jul 17, 2034 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01L2924/00014
- WIPO fieldSemiconductors
- WIPO sectorElectrical engineering
Abstract
A method of forming a pillar bump includes feeding a bond wire in a capillary. The capillary has a hole portion and a chamfer section arranged downstream of the hole portion. The hole portion has a length along a feed direction of the bond wire that is greater than a maximum diameter of the hole portion. The method further includes 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.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.