RE-activated lanthanide phosphate phosphors for PDP applications

Several mechanisms have been proposed for the degradation of currently avai lable plasma display panel (PDP) phosphors. The proposed mechanisms for deg radation include bombardment by energetic ions, low-energy electrons and hi gh-energy photons (VUV) from the Xe/Ne gas discharge. The limited lifetime exhibited by some of the PDP phosphors lead us to explore different rare ea rth-activated lanthanide phosphate phosphors, which may have improved lifet ime and luminance efficiency for PDP applications. Compared to silicate, bo rate- and oxide-based standard PDP phosphors, the excitation spectra of lan thanum phosphate-based phosphors exhibit high absorption in VUV region (100 -200 nm). A number of phosphate samples have been prepared by calcinating r equired quantities of respective rare earth nitrates in the presence of amm onium hydrogen phosphate and flux at solid stare reaction temperatures, Var ious preparative conditions are considered to improve the overall efficienc y and morphology. The excitation (VUV region) and emission spectra (UV-visi ble) from various RE-doped lanthanide phosphate phosphors samples are prese nted. The feasibility of employing these phosphors in PDP applications has been described. (C) 2000 Elsevier Science B.V. All rights reserved.