Minimizing flux residue by controlling amount of moisture during reflow
US6409070B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Sep 18, 2000 |
| Grant date | Jun 25, 2002 |
| Priority date | — |
| Expiry date | Sep 18, 2020 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH05K3/3489
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A method of manufacturing a flip-chip semiconductor device by attaching a semiconductor die to a substrate using solder comprises the steps of applying a no-clean flux to the semiconductor die and the substrate; heating the solder and the flux in a furnace to bond the semiconductor die to the substrate; and underfilling between the semiconductor die and the substrate. While the solder and flux is being heated, a reducing atmosphere in the furnace is being measured to determine the moisture content. When the moisture content exceeds a threshold amount, a signal will be provided. A reflow furnace for practicing the method is also disclosed.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.