Luminescence enhancement of ZnGa2O4:Mn2+ by Ge4+ and Li+ doping

✍ Scribed by J.S Kim; H.L Park; G.C Kim; T.W Kim; Y.H Hwang; H.K Kim; S.I Mho; S.D Han

• Publisher: Elsevier Science
• Year: 2003
• Tongue: English
• Weight: 127 KB
• Volume: 126
• Category: Article
• ISSN: 0038-1098
• DOI: 10.1016/s0038-1098(03)00238-2

✦ Synopsis

Structural and optical properties of ZnGa 2 O 4 :Ge 4þ and ZnGa 2 O 4 :Ge 4þ , Li þ , Mn 2þ phosphors were investigated by using X-ray diffraction (XRD), photoluminescence (PL) and cathodoluminescence (CL) measurements. The XRD patterns show that Ge-doped ZnGa 2 O 4 has a spinel phase and its lattice constant increases with respect to ZnGa 2 O 4 . Emission wavelength shifts from 400 to 360 nm in comparison with ZnGa 2 O 4 when Ge is doped in ZnGa 2 O 4 and a peak related with oxygen defect was observed in Ge-doped ZnGa 2 O 4 . The CL luminance of ZnGa 2 O 4 :Ge 4þ , Li þ , Mn 2þ phosphors is seven times brighter than that of ZnGa 2 O 4 :Mn 2þ . This drastic luminance improvement can be attributed to Ge doping in ZnGa 2 O 4 acting as donor ion and Li doping resulting in increasing conductivity of ZnGa 2 O 4 . These results indicate that ZnGa 2 O 4 :Ge 4þ , Li þ , Mn 2þ phosphors hold promise for potential applications in field-emission display devices with high brightness operating in green spectral regions.