Electroluminescence from Cr3+ in Perovskite Thin-Film Phosphors Using LaAlO3 and LaGaO3 as Hosts

Abstract

We observed multicolor and near-infrared electroluminescence (EL) from perovskite oxide thin-film phosphors using Cr- and Ce-co-doped LaGaO3 and LaAlO3. These phosphor thin films were prepared by varying either Cr or Ce content using a combinatorial r.f. magnetron sputtering deposition method. Intense deep-red and weak yellow-green EL emissions were observed from thin-film electroluminescent (TFEL) devices fabricated using posannealed LaGaO3:Ce,Cr thin films. Intense near-infrared emission and yellow-green EL emissions were observed from TFEL devices fabricated using posannealed LaAlO3:Ce,Cr thin films. The highest EL intensity was obtained in TFEL devices using postannealed LaGaO3:Ce,Cr and LaAlO3:Ce,Cr phosphor thin films with Cr content approximetly 3 and 1at.%, respectively. All the observed emission peaks in EL from the LaGaO3:Ce,Cr and/or the LaAlO3:Ce,Cr phosphor thin films were assigned to either the emission originating from the transition in the Ce3+ and Cr3+ ions.