Transfer bump street, semiconductor flip chip and method of producing same
US6483195B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Mar 9, 2000 |
| Grant date | Nov 19, 2002 |
| Priority date | — |
| Expiry date | Mar 9, 2020 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH05K3/3473
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
The invention relates to a low-cost transfer bump sheet which is capable of transferring copper-cored solder bumps with high reliability of bonding to a semiconductor chip and which is capable of transferring bumps of various structures. The invention also relates to a low-cost semiconductor flip chip in which copper-cored solder bumps with high reliability of bonding are mounted on a semiconductor chip through the use of the transfer bump sheet. In the transfer bump sheet, metal posts of two or more layers are formed on a base sheet. The invention also relates to a method of manufacturing this semiconductor flip chip, which comprises the steps of forming the base sheet on a metal foil, forming a plating mask on the metal foil, forming a first solder layer (solder coating) on the metal foil by electrolytic plating or electroless plating, removing the plating mask, and forming a metal layer (metal core) of metal posts by the etching of the metal foil through the use of the formed first solder layer (solder coating) as an etching mask.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.