Increase of the Light Extraction Efficiency in InGaN-Based Light-Emitting Diodes Integrated with Microlens Arrays Made of UV-Curable Optical Adhesive

We fabricated InGaN-based 460-nm light-emitting diodes (LEDs) integrated with microlens arrays made of UV-curable optical adhesive and observed an enhancement of the LEDs' light output under current injection. The UV-curable optical adhesive microlens arrays were fabricated and integrated onto the tops of the LED chips by using one simple photolithography process. The light extraction of the microlensed LED was increased more than 1.23 times compared to that of the normal LED under a current injection of 20 mA. The ray tracing simulation results are qualitatively consistent with our experimental results. KCI Citation Count: 8