Method of planarizing die solder balls by employing a die's weight
US6465338B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Jul 10, 2000 |
| Grant date | Oct 15, 2002 |
| Priority date | — |
| Expiry date | Jul 10, 2020 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH05K2203/159
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
Disclosed is a method of planarizing an array of plastically-deformable electrical contacts on an integrated circuit. An integrated circuit is placed on a plate with an array of plastically-deformable electrical contacts substantially parallel to and facing the plate, thereby creating an assembly. The integrated circuit is placed above the plate such that the weight of the integrated circuit bears down on the array of plastically-deformable electrical contacts. The assembly is then heated sufficiently to cause individual ones of the plastically-deformable electrical contacts to locally soften but not to cause said individual ones of the electrical contacts to liquefy throughout their volumes. The weight of the integrated circuit applies a force to the softened plastically-deformable electrical contacts, thereby resulting in their planarization.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.