Many studies have set out to develop electrodes that are both highly conductive and transparent across a wide spectral region, from visible to deep UV (DUV). However, few solutions have been proposed because these two properties are mutually exclusive. In this paper, an AlN-based glass electrode film with a conducting filament formed by the application of an ac pulse is proposed as a solution, which exhibits a high transmittance in the DUV region (over 95.6% at 280 nm) and a low contact resistance with a p-Al0.4Ga0.6N layer (ρc = 3.2 × 10-2 Ω·cm2). The Ohmic conduction mechanism at the interface between the AlN film and the p-Al0.4Ga0.6N layers is fully examined using various analytical tools. This AlN film is finally applied to a 280 nm top-emitting light-emitting diode, to verify the validity of the method, which exhibits very stable operations with a forward voltage of 7.7 V at 20 mA, a light output power of 7.49 mW at 100 mA, and, most importantly, a record high external quantum efficiency of 2.8% after packaging.
Bibliographical noteFunding Information:
This work was supported by the National Research Foundation of Korea (NRF) Grant funded by the Korean government (no. 2016R1A3B1908249).
© 2017 American Chemical Society.
- deep-UV light-emitting diode
- direct Ohmic contact
- glass electrode
- pulsed electrical breakdown
- transparent conductive electrode
ASJC Scopus subject areas
- Materials Science(all)