Method for forming metal bumps
US7550375B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Dec 8, 2006 |
| Grant date | Jun 23, 2009 |
| Priority date | — |
| Expiry date | Dec 25, 2027 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH05K2203/0574
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A method for forming metal bumps is disclosed. Steps of the method include supplying a substrate containing a plurality of pads; forming a first photoresist layer on the substrate, herein the first photoresist layer covers the pads; performing a planarization step to remove a portion of the first photoresist layer so as to expose the pads; forming a conductive layer on the first photoresist layer and the pads; electroplating a metal layer on the conductive layer; forming a patterned second photoresist layer on the metal layer; a portion of the metal layer and the conductive layer which are not covered by the patterned second photoresist layer is removed by using the patterned second photoresist layer as a mask; removing the patterned second photoresist layer; and forming a solder mask on the substrate, wherein the solder mask has a plurality of openings to expose the metal layer located on the pads.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.