ZnO light-emitting devices with a lifetime of 6.8 hours

Lithium-nitrogen doped p-type Mg0.25Zn0.75O films have been realized, and p-Mg0.25Zn0.75O/n-ZnO single-heterostructured light-emitting devices (LEDs) have been constructed. Obvious emission at around 392 nm has been observed from the LEDs under the injection of continuous current, which can be attributed to the near-band-edge emission of ZnO. The LED can work continuously for 6.8 h under a continuous current of 20 mA, revealing the good reliability of the LED. The results reported in this letter reveal that reliable ZnO-based LEDs can be realized, thus high-performance ZnO-based LEDs may be promised in the future.