The influence of oxygen partial pressure on material properties of Eu³⁺-doped Y₂O₂S thin film deposited by Pulsed Laser Deposition

详细信息    查看全文

• 作者：A.G. Ali^a ; ^{aliag@qwa.ufs.ac.za" class="auth_mail" title="E-mail the corresponding author} ; B.F. Dejene^a ; H.C. Swart^b
• 关键词：Thin film ; Phosphor ; Y2O2S ; Eu3+ ; PLD ; XRD ; PL
• 刊名：Physica B: Physics of Condensed Matter
• 出版年：2016
• 出版时间：1 January 2016
• 年：2016
• 卷：480
• 期：Complete
• 页码：174-180
• 全文大小：1485 K

文摘

Eu³⁺-doping has been of interest to improve the luminescent characteristics of thin-film phosphors. Y₂O₂S:Eu³⁺ films have been grown on Si (100) substrates by using a Pulsed Laser Deposition technique. The thin films grown under different oxygen deposition pressure conditions have been characterized using structural and luminescent measurements. The X-ray diffraction patterns showed mixed phases of cubic and hexagonal crystal structures. As the oxygen partial pressure increased, the crystallinity of the films improved. Further increase of the O₂ pressure to 140 mtorr reduced the crystallinity of the film. Similarly, both scanning electron microscopy and Atomic Force Microscopy confirmed that an increase in O₂ pressure affected the morphology of the films. The average band gap of the films calculated from diffuse reflectance spectra using the Kubelka–Munk function was about 4.75 eV. The photoluminescence measurements indicated red emission of Y₂O₂S:Eu³⁺ thin films with the most intense peak appearing at 619 nm, which is assigned to the ⁵D₀–⁷F₂ transition of Eu³⁺. This most intense peak was totally quenched at higher O₂ pressures. This phosphor may be a promising material for applications in the flat panel displays.