Method to improve bump reliability for flip chip device
US8497584B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Mar 26, 2004 |
| Grant date | Jul 30, 2013 |
| Priority date | — |
| Expiry date | Jul 29, 2030 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01L2924/351
- WIPO fieldSemiconductors
- WIPO sectorElectrical engineering
Abstract
A new method is provided for the creation of a solder bump. Conventional methods are initially followed, creating a patterned layer of Under Bump Metal over the surface of a contact pad. A layer of photoresist is next deposited, this layer of photoresist is patterned and developed creating a resist mask having a T-shape opening aligned with the contact pad. This T-shaped opening is filled with a solder compound, creating a T-shaped layer of solder compound on the surface of the layer of UBM. The layer of photoresist is removed, exposing the created T-shaped layer of solder compound, further exposing the layer of UBM. The layer of UBM is etched using the T-shaped layer of solder compound as a mask. Reflow of the solder compound results in creating a solder ball.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.