Optoelectronic device encapsulant
US6356686B1 · kind B1 · utility
Assignee
Inventor
Key dates
| Filing date | Sep 3, 1999 |
| Grant date | Mar 12, 2002 |
| Priority date | — |
| Expiry date | Sep 3, 2019 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG02B6/4292
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
An optically clear encapsulant for optoelectronic packages exhibits a suitably high viscosity both to replace a silicon nitride passivation layer required on a VCSEL die and to fill a gap between the die and an optical coupler, preventing light signal degradation. The encapsulant exhibits optical transparency to light having a wavelength of about 850 nanometers (nm) with substantially no Mie scattering since particulate fillers are not required to modulate viscosity in the encapsulant. Also, the encapsulant further seals wire bonds between the die and a cable header to prevent abrasive wear. The gap-filling encapsulant is particularly suitable for use with vertical cavity surface emitting laser (VCSEL) technology. The encapsulant includes prior to curing, a difunctional acrylate epoxy resin exhibiting pseudoplastic flow and a viscosity of greater than about 0.7×106 centipoise. Accordingly, a method of manufacturing an optical subassembly may eliminate a separate passivation step and instead fill the gap between the die and optical coupler with an optically clear encapsulant.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.