Ultraviolet-Visible Electroluminescence of a p-ZnO:As-Si Device Formed by the GaAs Interlayer Doping Method

摘要

Arsenic doped p-type ZnO films were grown on n-type silicon substrates using the GaAs interlayer doping method.Under our growth conditions the main doping element is arsenic,which was confirmed by x-ray photoelectroscopy.X-ray diffraction measurements revealed that the p-ZnO:As film was still in the (002) preferred orientation.The Hall test showed that the hole concentration of the p-ZnO:As film was 2.6 × 1017 cm-3.The acceptor level was located at 135 meV above the valance band maximum,according to the low-temperature photoluminescence results.We then fabricated a p-ZnO:As-Si hetero junction light-emitting device.Its current-voltage curve showed the typical rectifying behavior of a p-n diode.At forward current injections,the electroluminescence peaks,which cover the ultraviolet-to-visible region,could be clearly detected.ZnO is a Ⅱ-Ⅵ compound semiconductor with a wide direct gap (3.37eV) and a high exciton binding energy (60meV).It has been studied as the candidate material for ultraviolet (UV) light emitting devices (LEDs).Many methods have been used to prepare ZnO films.[1,2] Among them,the metal organic chemical vapor deposition (MOCVD) method has its own excellent advantages in industrial applications.Today,the preparation of p-ZnO is still a challenge.%Arsenic doped p-type ZnO films were grown on n-type silicon substrates using the GaAs interlayer doping method. Under our growth conditions the main doping element is arsenic, which was confirmed by x-ray photoelectroscopy. X-ray diffraction measurements revealed that the p-ZnO:As Him was still in the (002) preferred orientation. The Hall test showed that the hole concentration of the p-ZnO:As film was 2.6 × 1017 cm-3. The acceptor level was located at 135 meV above the valance band maximum, according to the low-temperature photoluminescence results. We then fabricated a p-ZnO:As-Si heterojunction light-emitting device. Its current-voltage curve showed the typical rectifying behavior of a p-n diode. At forward current injections, the electroluminescence peaks, which cover the ultraviolet-to-visible region, could be clearly detected.