Electroless Silver Plating Reflectors to Boost the Performance of Vertical Light-Emitting Diodes

In this paper, we experimentally demonstrated a novel approach known as electroless silver plating (ESP) for the fabrication of Ag-only reflectors on vertical light-emitting diodes (VLEDs). The Ag reflector that was obtained through the ESP approach shows a higher reflectance of 83% and a lower contact resistivity of 6 * 10-3 Ω · cm2 with p-GaN, compared with that fabricated through the conventional electron beam (EB) approach, which shows a reflectance of 75% and a contact resistivity of 6.2 * 10-2 Ω · cm2, respectively. Improvements in the light output intensity-current (L-I) and current-voltage (I-V) results in VLEDs, which originated from the high reflectance and low-contact resistivity of the incorporated ESP-Ag reflector. Our result opens up an alternative and promising way to substitute the traditional EB approach for Ag-based reflector fabrication and, thus, is practically meaningful in real device fabrication, such as with VLEDs.

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