AVS 53rd International Symposium
    Thin Film Tuesday Sessions
       Session TF-TuP

Paper TF-TuP7
Investigation of Luminescence and Microstructure of Sputter-deposited Zinc Gallate Thin Films Doped with Manganese

Tuesday, November 14, 2006, 6:00 pm, Room 3rd Floor Lobby

Session: Thin Film Poster Session
Presenter: J.H. Kim, Chungbuk National University, Korea
Authors: J.H. Kim, Chungbuk National University, Korea
P.H. Holloway, University of Florida
Correspondent: Click to Email
Luminescent characteristics and microstructural properties of manganese-doped zinc gallate (ZnGa@sub2@O@sub4@:Mn) thin films have been studied. The ZnGa@sub2@O@sub4@:Mn films were prepared by radio frequency (RF) planar magnetron sputtering from a 2 mol% Mn-doped ZnGa@sub2@O@sub4@ target in an oxygen-argon mixture atmosphere. The half-stack alternating-current thin-film electroluminescent (ACTFEL) devices were constructed using an inverted single-insulating layer structure, ITO/ZnGa@sub2@O@sub4@:Mn/BaTiO@sub3@/Al. First, approximately 600 nm of ZnGa@sub2@O@sub4@:Mn was deposited on the 200µm-thick BaTiO@sub3@ ceramic substrates. The samples were then annealed at 800°C in air for 3 hours, followed by ITO sputter deposition and Al metal evaporation. The fabricated devices were tested using a bipolar trapezoidal drive waveform with rise and fall times of 5 µs and a hold time of 30 µs. The drive frequency was 2.5 kHz (5k light pulses per second). Green emission peaked at 508 nm was obtained from the device and it was attributed to the @super4@T@sub1@ - @super6@A@sub1@ transition in Mn@super2+@ ion. The color coordinates of the emission were x=0.11 and y=0.7 in the CIE chromaticity diagram. The threshold voltage for the emission was ~100 V and the brightness was 28 cd/m@super2@ measured at 30 volts above the threshold voltage. The photoluminescent and cathodoluminescent characteristics of the ZnGa@sub2@O@sub4@:Mn films deposited on Si substrates were also investigated. The emission peaks of both PL and CL were at ~505 nm, and the emission spectra were identical to the EL spectra. Both PL and CL brightness was strongly correlated with the microstructural differences in ZnGa@sub2@O@sub4@:Mn films produced by difference in gas pressure during sputter deposition.