AVS 47th International Symposium
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       Session FP-TuM

Paper FP-TuM4
Growth and Characterization of Pulsed Laser Deposited Zn2GeO4:Mn Green Thin Film Phosphors

Tuesday, October 3, 2000, 9:20 am, Room 313

Session: Luminescent Materials
Presenter: T. Feng, University of Florida
Authors: T. Feng, University of Florida
P.H. Holloway, University of Florida
D. Kumar, University of Florida
M. Davidson, University of Florida
J.M. Fitz-Gerald, Naval Research Laboratory
H. Kim, Naval Research Laboratory
D.P. Norton, Oak Ridge National Laboratory
Y.E. Lee, Oak Ridge National Laboratory
Correspondent: Click to Email
Pulsed laser deposition of Zn2GeO4:Mn oxide thin films on glass/ITO/ATO and Al2O3/Au/PZT substrates, which are potentially used for electroluminescent displays, has been investigated. A stoichiometric target Zn2GeO4:Mn was obtained by sintering a mixture of ZnO, GeO2 and MnO2 powder in air at 1020oC for 24 hrs. A green photoluminescence peak was obtained from the target at a wavelength of 540nm. Films were pulsed laser deposited on glass/ITO/ATO and Al2O3/Au/PZT substrate at an O2 pressure of 150~200 mTorr and a laser density of 0.8~1.6J/cm2. All deposited films were Zn-deficient in contrast to the stoichiometric target ratio for Zn/Ge of 2. The films deposited at 250oC on glass/ITO/ATO showed a Zn/Ge ratio of 1.02, while films deposited at 800oC were more Zn-deficient with a ratio of 0.82. The Zn2GeO4:Mn films deposited at 250oC on glass/ITO/ATO were amorphous, but recrystallized upon rapid thermal annealing at 800oC in Ar for 1 min. Photoluminescence with an intensity of 46 cd/m2 at a peak wavelength of 536nm was obtained from a 300nm film deposited on Al2O3/Au/PZT at 250oC followed by post-annealing at 750oC in air for 1 hr. Photoluminescence of 11 cd/m2 was obtained from a film deposited on glass/ITO/ATO followed by rapid thermal annealing at 800oC in Ar for 1 min. A surface particulate density of 2.42x105/cm2 was observed in the film deposited on glass/ITO/ATO substrate at a temperature of 250oC, O2 ambient pressure of 200 mTorr and laser density of 0.8mJ/cm2. Films deposited at 800oC showed a large density of pinholes, in addition to surface particulates. Annealing in O2 ambient resulted in a better PL intensity compared to annealing in air or Ar ambient.