Ag-based hollow reflective electrode on thin p-GaN layer for improving the light output efficiency of AlGaN-based deep-ultraviolet light-emitting diodes

In this work, we used an Ag-based hollow reflective electrode on thin p-GaN to enhance the light output power (LOP). Light emitted in the region between the square Ag/Ti arrays will be reflected by the Al reflective mirror enhancing the LOP. The smaller size of square Ag/Ti arrays is better for I-V characteristics and LOP. Within the range of the coverage ratios of square Ag/Ti arrays in our work, an 8.6% increase in the LOP was got. we speculate that larger coverage ratios can improve the LOP further. The design of square Ag/Ti arrays/Al p-electrodes will be an excellent technique to enhance light extraction.