Photoluminescence characteristics of pulsed laser deposited Y2-xGdxO3:Eu3+ thin film phosphors

Y2-xGdxO3:Eu3+ phosphor thin films were grown on Si (100) and Al2O3 (0001) substrates using a pulsed laser deposition (PLD) technique. Thin film phosphors were deposited by changing the substrates and the processing conditions (substrate temperature and oxygen pressure). The films grown under different deposition conditions have been characterized using microstructural and luminescent measurements. The photoluminescence (PL brightness data obtained from the Y2-xGdxO3:Eu3+ films grown under optimized conditions have indicated that Al2O3 (0001) and Si (100) substrates are promising substrate for the growth of high quality Y2-xGdxO3: EU3+ thin film red phosphor. The films were preferentially (222) oriented in both Si (100) and Al2O3 (0001) cases and the films grown on Al2O3(0001) substrate exhibit the superior crystallization and photoluminescent properties. The highest emission intensity was observed with Y1.35Gd0.6O3:Eu3+ films grown on Al2O3 (0001) substrate, whose brightness increased by a factor of 3.7 in comparison with that of the films grown on Si (100) substrate. The PL intensity of the Y2-xGdxO3: Eu3+ films are highly dependent on the crystallinity and surface roughness of the films. The PL intensity and surface roughness have similar behaviour as a function of not only oxygen pressure but also substrate temperature. This phosphor may be promising for application to the flat panel displays. (C) 2004 Elsevier B.V. All rights reserved.