Abstract
The p-electrode of blue light-emitting diodes (LED) chips has a low transmittance on the blue light spectrum. The blue light emitted from the quantum wells under the p-electrode will be severely absorbed by p-electrode, which cause a decrease in blue light extraction efficiency (LEE). In this study, we first designed a current blocking layer (CBL) structure with the blue light reflection through the simulation software. The simulation results show that this structure can effectively improve blue LEE, and then, this structure was verified by experiment. Electroluminescence measurement results show that LED with Metal-distributed Bragg reflector (M-DBR) CBL exhibited better optical performance than the LED with SiO2 CBL and DBR CBL. It was found that M-DBR CBL can effectively increase the blue light reflectivity and prevent the light absorption from the metal p-electrode to improve LED’ blue LEE.
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This work was supported by the National High Technology Program of China 2014AA032606 and 2013AA03A101, the National Natural Science Foundation of China 61306050.
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Liu, N., Yi, X., Wang, L. et al. Light extraction improvement of blue light-emitting diodes with a Metal-distributed Bragg reflector current blocking layer. Appl. Phys. A 118, 863–867 (2015). https://doi.org/10.1007/s00339-014-8923-0
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DOI: https://doi.org/10.1007/s00339-014-8923-0