| Summary: | 碩士 === 逢甲大學 === 化學工程學所 === 93 === Field Emission Display should be operated under vacuum ,with cold cathode field emitters to provide the electron emission. But the sulfide phosphor will be decomposed by high energy electron bombardment, harmful gases such as SO、SO2 were generated.The sulfur related gases coming from the phosphor can dramatically reduce the electron emission efficiency of the cathodes and the degradation of the phosphor surface also leads to deteriorated phosphor performace.
To circumvent these disadvantages, the oxide phosphors of (Y2O3)( ZnO) :Tb derived from solid state method were chosen in our study. X-ray diffractometer (XRD) were used in the characterization of crystalline structure、Fluorescent Spectrometer(PL) were used in the characterization of luminescence、Scanning Electron Microscope(SEM) were used in the characterization of phosphor surface morphology.
The XRD pattern of the sintering phosphor, Y2O3:Tb under air atmosphere did not give the terbium oxide diffraction peak, but ZnO:Tb did show the terbium oxide diffraction peak. Phosphor of (Y2O3)( ZnO) :Tb also show the terbium oxide diffraction peak. The LiCl flux has no singnificant effect on the degree of crystallization of yttrium oxide and of zinc oxide .
The best terbium doped concentration is 1 mol% for yttrium oxide and the addition of the LiCl flux does not increase the luminescent intensity of Y2O3:Tb 5D4→7Fj but does increase in the 5D3→7Fj transition. When flux concentration is higher than 0.3 mol%, the luminescent intensity of zinc oxide is decreased when the flux concentration is increased . For yttrium oxide and zinc oxide co-doped with terbium, the luminescent intensity was enhanced by the mixture.
|
|---|
