Study on the luminescence properties of n-ZnO/i-NiO/n-GaN isotype heterojunction diodes

► The n-ZnO/i-NiO/n-GaN isotype heterojunction diode was fabricated by MOCVD. ► NiO could be used as the effective electron blocking layer for n-ZnO/n-GaN heterojunction. ► The dielectric NiO layer could enhance the UV emission efficiency of the LED greatly.