Light Output Improvement of InGaN-Based Light-Emitting Diodes by Microchannel Structure

We propose a microchannel structure with deep holes to enhance the extraction efficiency of InGaN-based light-emitting diodes (LEDs). Two different depth microchannel LEDs are examined experimentally. One has air holes penetrated through the active layer and the other does not. It is found that the light extraction efficiency in the LED with the penetrated air holes is significant h larger than that in the LED without penetrating holes. The reason can be attributed to the microchannel waveguide behaviors. In comparison to the conventional LEDs, the light output power of our fabricated LEDs with and without penetrating holes improved by 43.5% and 5.1%, respectively.

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