Encapsulated ball bonding apparatus and method
US5938105A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Jul 9, 1997 |
| Grant date | Aug 17, 1999 |
| Priority date | — |
| Expiry date | Jul 9, 2017 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01L2924/20753
- WIPO fieldSemiconductors
- WIPO sectorElectrical engineering
Abstract
An improved capillary construction that includes a cavity suitable for at least partially molding a ball bond during a ball bonding operation as well as methods for wire bonding utilizing such a capillary are described. More specifically, a distal end of a bonding wire that passes through the capillary is ultrasonically welded to a bonding surface in a manner such that the cavity molds a significant portion of the ball bond during the ball bonding operation. The described arrangement permits the bonding force applied by the bonding machine that drives the capillary to be significantly reduced or eliminated. In some embodiments, the capillary is positioned at a predetermined standoff height relative to the bonding surface. The described arrangements have numerous advantages and permits bonding to bonding surfaces that are heated to a temperatures of less than approximately 150 degrees centigrade during the ultrasonic welding step. The resultant bonds tend to have significant intermetallic bonding over a majority of a contact surface between the ball bond and the bonding surface. The described capillary and methods works well with fine pitch devices, including devices having pitches …
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.