Structural and Luminescent Properties of Eu, Mg Co-doped GaN

Eu and Mg were implanted into the GaN thin films grown by metal-organic chemical vapor deposition. Mg dose was kept as 5×1013 cm-2, while Eu dose was 1×1014, 5×1014 and 1×1015 cm-2. The structural and luminescent properties were investigated via X-ray diffraction (XRD), Raman and photoluminscence spectra. The results of X-ray diffraction and Raman scattering both consistently revealed that the stress inside the GaN:Eu sample and GaN:Eu, Mg sample had the same tendency to change with the Eu implantation dose. The implantation dose of Eu was increased from 1×1014 to 5×1014 cm-2, resulting in lattice contraction and tensile stress. The implantation dose of Eu was increased from 5×1014 to 1×1015 cm-2, resulting in lattice expansion and compressive stress. The results of photoluminescence indicated that the presence of Mg in GaN:Eu, Mg samples could reduce the intrinsic defects around Eu, decrease yellow light emission, and enhance the energy transfer between GaN matrix and Eu3+. The presence of Mg led to an overall enhancement of the Eu-related emission peak intensity, did not change the Eu-related luminescence peak position, and also did not introduce new luminescence peaks. With the increase of ratio of Eu dose to Mg dose, the enhancement factor of Eu luminescence intensity first increased and then decreased. The optimized Eu/Mg dose ratio was 10:1 and Eu luminescence intensity was increased to 6.6 times of GaN:Eu. © Editorial Office of Chinese Journal of Rare Metals. All right reserved.