Process and apparatus to remove closely spaced chips on a multi-chip module
US6216937A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Dec 22, 1999 |
| Grant date | Apr 17, 2001 |
| Priority date | — |
| Expiry date | Dec 22, 2019 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01L24/98
- WIPO fieldSemiconductors
- WIPO sectorElectrical engineering
Abstract
A process and apparatus for removing flip chips with C4 joints mounted on a multi-chip module by applying a tensile force to one or more removal member bonded to the back of one or more flip chips during heating of the module to a temperature sufficient to cause the C4 joints to become molten. The tensile force can either be a compressed spring, or a bimetallic member which is flat at room temperature and becomes curved when heated to such temperature, or a memory alloy whose original shape is curved and which is bent flat at room temperature but returns to its original curved shape when heated to such temperature. An adhesive is used to bond the removal member to the chip to be removed and is a low temperature, fast curing adhesive with high temperature tolerance after curing.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.