Energy Express Focus Issue: Optics in LEDs for Lighting

Energy Express reports that research highlights improved efficiency, reduced costs for solid-state lighting applications using tungsten.

The press release is quoted as saying,

In order to improve extraction efficiency, hence external quantum efficiency, of LED devices, photons generated in the active region should escape out of the naturally formed slab waveguide structure formed by the LEDs’ epitaxial layers. A paper by Seong-Ju Park, et al. demonstrates that tungsten metal can be used not only as a mask for epitaxial lateral overgrowth but also for the formation of an air void underneath it to improve both internal quantum efficiency and extraction efficiency of the LEDs. Whereas several similar approaches have been demonstrated, this study is unique in the formation of an air void as an optical scatterer without resorting to a complicated etching process.

For the complete press release, click here.