title: MQWs InGaN/GaN LED with embedded micro-mirror array in the epitaxial-lateral-overgrowth gallium nitride for light extraction enhancement.
abstract: Multi-quantum wells (MQWs) InGaN/GaN LEDs, 300 microm x 300 microm chip size, were fabricated with Ta(2)O(5) / SiO(2) dielectric multi-layer micro-mirror array (MMA) embedded in the epitaxiallateral- overgrowth (ELOG) gallium nitride (GaN) on the c-plane sapphire substrate. MQWs InGaN/GaN LEDs with ELOG embedded patterned SiO(2) array (P-SiO(2)) of the same dimension as the MMA were also fabricated for comparison. Dislocation density was reduced for the ELOG samples. 75.2% light extraction enhancement for P-SiO(2)-LED and 102.6% light extraction enhancement for MMA-LED were obtained over the standard LED. We showed that multiple-diffraction with high intensity from the MMA redirected the trap lights to escape from the LED causing the light extraction enhancement.
authors.affiliation: Institute of Photonics Technologies, National Tsing Hua University, Hsinchu, Taiwan, 30013, ROC.
authors.forename: Chen-Yang
authors.initials: CY
authors.lastname: Huang
authors.forename: Hao-Min
authors.initials: HM
authors.lastname: Ku
authors.forename: Chen-Zi
authors.initials: CZ
authors.lastname: Liao
authors.forename: Shiuh
authors.initials: S
authors.lastname: Chao
mesh_terms: D003460:Crystallization / Q000379:methods*; D005708:Gallium / Q000737:chemistry*; D007909:Lenses; D008027:Light; D008029:Lighting / Q000295:instrumentation*; D008904:Miniaturization; D012542:Scattering, Radiation; D012666:Semiconductors
chemical_list: C473348:gallium nitride; D005708:Gallium