Metal nanoink and process for producing the metal nanoink, and die bonding method and die bonding apparatus using the metal nanoink
US8328928B2 · kind B2 · utility
Assignees
Inventors
Key dates
| Filing date | Jul 8, 2009 |
| Grant date | Dec 11, 2012 |
| Priority date | — |
| Expiry date | Jul 8, 2029 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01L2924/12044
- WIPO fieldSemiconductors
- WIPO sectorElectrical engineering
Abstract
Metal nanoink (100) for bonding an electrode of a semiconductor die and an electrode of a substrate and/or bonding an electrode of a semiconductor die and an electrode of another semiconductor die by sintering under pressure is produced by injecting oxygen into an organic solvent (105) in the form of oxygen nanobubbles (125) or oxygen bubbles (121) either before or after metal nanoparticles (101) whose surfaces are coated with a dispersant (102) are mixed into the organic solvent (105). Bumps are formed on the electrode of the semiconductor die and the electrode of the substrate by ejecting microdroplets of the metal nanoink (100) onto the electrodes, the semiconductor die is turned upside down and overlapped in alignment over the substrate, and then, the metal nanoparticles of the bumps are sintered under pressure by pressing and heating the bumps between the electrodes. As a result, generation of voids during sintering under pressure is minimized.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.