Semiconductor LED flip-chip having low refractive index underfill
US6455878B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | May 15, 2001 |
| Grant date | Sep 24, 2002 |
| Priority date | — |
| Expiry date | May 15, 2021 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH10H20/857
- WIPO fieldSemiconductors
- WIPO sectorElectrical engineering
Abstract
In accordance with the invention, a difference in index of refraction is created at the mesa wall of a III-nitride flip chip light emitting device. The step in index of refraction reflects much of the light incident on the mesa wall back into the device where it can be usefully extracted. In some embodiments, a solder wall on the submount or a high index gel coating the light emitting device and the submount creates a sealed gap between the light emitting device and the submount. The gap is filled with a material having a low index of refraction. In other embodiments, a high index material covers the substrate of the light emitting device, and a low index material fills the gap between the submount and the light emitting device.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.