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Enhanced light extraction efficiency of Eu-related emission from a nano-patterned GaN layer grown by MOCVD.

ABSTRACT: Eu-doped GaN is a promising material for the active layer in red light emitting diodes. Although the output power of LEDs based on GaN:Eu has been increasing by a combination of structural and growth optimizations, there is still a significant limitation resulting from a poor light extraction efficiency, typical for high refractive index materials. Here we studied nanostructuring of the top of the optical active layer by nano-cubes for enhancement of the light extraction efficiency, and its effect on the optical emission characteristics. By etching nano-cubes into the active layer, we observed an increase in directional light output power of Eu3+ ions of up to 60%, as well as a grating effect. Simultaneously, the absorption of excitation light into the optical active layer was improved, leading to a 12.8 times increase of output power per available Eu3+ ion.

SUBMITTER: Lesage A

PROVIDER: S-EPMC6414605 | biostudies-literature | 2019 Mar

REPOSITORIES: biostudies-literature

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Enhanced light extraction efficiency of Eu-related emission from a nano-patterned GaN layer grown by MOCVD.

Lesage A A Timmerman D D Inaba T T Gregorkiewicz T T Fujiwara Y Y

Scientific reports 20190312 1

Eu-doped GaN is a promising material for the active layer in red light emitting diodes. Although the output power of LEDs based on GaN:Eu has been increasing by a combination of structural and growth optimizations, there is still a significant limitation resulting from a poor light extraction efficiency, typical for high refractive index materials. Here we studied nanostructuring of the top of the optical active layer by nano-cubes for enhancement of the light extraction efficiency, and its effe ...[more]

PMID: 30862946

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