Methods for protecting a die surface with photocurable materials
US8568961B2 · kind B2 · utility
Assignee
Inventor
Key dates
| Filing date | Nov 25, 2009 |
| Grant date | Oct 29, 2013 |
| Priority date | — |
| Expiry date | Jan 6, 2030 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01L2924/351
- WIPO fieldSemiconductors
- WIPO sectorElectrical engineering
Abstract
In a first aspect of the present invention, a method for manufacturing a flip chip package is provided comprising the steps of a) providing a chip having electrically conductive pads on an active surface thereof, b) coating at least a portion the chip with a protectant composition comprising a polymerizable component comprising a thermosetting epoxy resin, at least 50 weight percent of a substantially transparent filler having a coefficient of thermal expansion of less than 10 ppm/° C., a photoinitator, and a solvent carrier, wherein the protectant composition comprises a thixotropic index of less than 1.5, c) masking the coated chip to mask areas where vias through the protectant are desired, d) exposing the masked chip to a light source sufficient to partially crosslink the protectant composition in the unmasked areas, e) removing the uncured portions of the protectant composition thereby creating vias through the protectant composition to the electrically conductive pads on the surface of the chip, f) applying an electrically conductive material to the chip through the vias, wherein the electrically conductive material protrudes from the surface of the protectant composition, an…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.