STT-MRAM flip-chip magnetic shielding and method for producing the same
US10347826B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Jan 8, 2018 |
| Grant date | Jul 9, 2019 |
| Priority date | — |
| Expiry date | Jan 8, 2038 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01L2924/3025
- WIPO fieldSemiconductors
- WIPO sectorElectrical engineering
Abstract
Methods of magnetically shielding a perpendicular STT-MRAM structure on all six sides within a flip-chip package and the resulting devices are provided. Embodiments include forming a passivation stack over an upper surface of a wafer and outer portions of an Al pad; forming a polymer layer over the passivation stack; forming a UBM layer over the Al pad, portions of the polymer layer and along sidewalls of the polymer layer; forming a T-shaped Cu pillar over the UBM layer; forming a μ-bump over the T-shaped Cu pillar; dicing the wafer into a plurality of dies; forming an epoxy layer over a bottom surface of each die; forming a magnetic shielding layer over the epoxy layer and along sidewalls of each die, the epoxy layer, the passivation stack and the polymer layer; and connecting the μ-bump to a package substrate with a BGA balls.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.