Vibrating template method of placing solder balls on the I/O pads of an integrated circuit package
US5839191A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jan 24, 1997 |
| Grant date | Nov 24, 1998 |
| Priority date | — |
| Expiry date | Jan 24, 2017 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T29/49149
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
Solder balls are placed onto multiple I/O pads of an integrated circuit package by the steps of a) providing a template with a channel which has multiple openings on a surface of the template that match the pattern of the I/O pads; b) pouring a plurality of the solder balls onto the surface of the template; c) vibrating the template and thereby seating a respective solder ball in each of the template openings; d) turning the template over, after the vibrating step and while a vacuum is applied to the channel, to remove excess solder balls from the template; and e) removing the vacuum from the channel when the solder balls on the turned over template are aligned to the I/O pads of the integrated circuit package. Due to the vibrating step, the solder balls settle in the template openings in a position where vacuum leaks past the solder balls become minimized; and that stops the solder balls from dropping out of the template openings when the template is turned over. Also, since the steps a-d place the solder balls on all of the I/O pads in parallel, the time in which those steps are performed is many times smaller than the time in which a pick and place machine can put the solder bal…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.