Method for forming multilayer indium bump contacts
US5393696A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Oct 26, 1993 |
| Grant date | Feb 28, 1995 |
| Priority date | — |
| Expiry date | Oct 26, 2013 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S438/94
- WIPO fieldSemiconductors
- WIPO sectorElectrical engineering
Abstract
A method for forming multilayer bump contacts for use in flip-chip bump bonding and the like. The method comprises applying a base layer to a substrate and then applying a malleable conductive layer to the base layer. In a first embodiment, individual bump contacts are formed by removing portions of the base layer and malleable layer such that a plurality of bump contacts are formed. In a second embodiment a photoresist and etching process is used. The need to precisely align a mark to define the position of the malleable layer relative to the base layer is eliminated since the positions of the malleable layer and the base layer are defined simultaneously in both embodiments. Thus, the number of process steps is reduced, yield is increased, and alignment accuracy is improved.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.