Publisher : The Korean Microelectronics and Packaging Society
DOI : 10.6117/kmeps.2015.22.4.071
Title & Authors
Study on the Electrode Design for an Advanced Structure of Vertical LED Park, Jun-Beom; Park, Hyung-Jo; Jeong, Tak; Kang, Sung-Ju; Ha, Jun-Seok; Leem, See-Jong;
Recently, light emitting diodes (LEDs) have been studied to improve their efficiencies for the uses in various fields. Particularly in the aspect of chip structure, via hole type vertical LED chip is developed for improvement of light output power, and heat dissipations. However, current vertical type LEDs have still drawback, which is current concentration around the n-contact holes. In this research, to solve this phenomenon, we introduced isolation layer under n-contact electrodes. With this sub-electrode, even though the active area was decreased by about 2.7% compared with conventional via-hole type vertical LED, we could decrease the forward voltage by 0.2 V and wall-plug efficiency was improved approximately 4.2%. This is owing to uniform current flow through the area of n-contact.
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