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Title: Near-infrared electroluminescence at room temperature from neodymium-doped gallium nitride thin films

Abstract

Strong near-infrared (NIR) electroluminescence (EL) at room temperature from neodymium (Nd)-doped gallium nitride (GaN) thin films is reported. The Nd-doped GaN films were grown by radio-frequency planar magnetron cosputtering of separate GaN and metallic Nd targets in a pure nitrogen ambient. X-ray diffraction data did not identify the presence of any secondary phases and revealed that the Nd-doped GaN films had a highly textured wurtzite crystal structure with the c-axis normal to the surface of the film. The EL devices were fabricated with a thin-film multilayered structure of Al/Nd-doped GaN/Al{sub 2}O{sub 3}-TiO{sub 2}/indium-tin oxide and tested at room temperate. Three distinct NIR EL emission peaks were observed from the devices at 905, 1082, and 1364 nm, arising from the radiative relaxation of the {sup 4}F{sub 3sol2} excited-state energy level to the {sup 4}I{sub 9sol2}, {sup 4}I{sub 11sol2}, and {sup 4}I{sub 13sol2} levels of the Nd{sup 3+} ion, respectively. The threshold voltage for all the three emission peaks was {approx}150 V. The external power efficiency of the fabricated EL devices was {approx}1x10{sup -5} measured at 40 V above the threshold voltage.

Authors:
;  [1];  [2]
  1. Portland Technology Development, Intel Corporation, Hillsboro, Oregon 97124 (United States)
  2. (United States)
Publication Date:
OSTI Identifier:
20632770
Resource Type:
Journal Article
Resource Relation:
Journal Name: Applied Physics Letters; Journal Volume: 85; Journal Issue: 10; Other Information: DOI: 10.1063/1.1781745; (c) 2004 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; ALUMINIUM; ALUMINIUM OXIDES; CRYSTAL STRUCTURE; DEPOSITION; DOPED MATERIALS; ELECTROLUMINESCENCE; EXCITED STATES; GALLIUM NITRIDES; INDIUM OXIDES; MAGNETRONS; NEODYMIUM IONS; NITROGEN; RADIOWAVE RADIATION; SEMICONDUCTOR MATERIALS; TEMPERATURE RANGE 0273-0400 K; TEXTURE; THIN FILMS; TIN OXIDES; TITANIUM OXIDES; X-RAY DIFFRACTION

Citation Formats

Kim, Joo Han, Holloway, Paul H., and Department of Materials Science and Engineering, University of Florida, Gainesville, Florida 32611-6400 and MICROFABRITECH, University of Florida, Gainesville, Florida 32608. Near-infrared electroluminescence at room temperature from neodymium-doped gallium nitride thin films. United States: N. p., 2004. Web. doi:10.1063/1.1781745.
Kim, Joo Han, Holloway, Paul H., & Department of Materials Science and Engineering, University of Florida, Gainesville, Florida 32611-6400 and MICROFABRITECH, University of Florida, Gainesville, Florida 32608. Near-infrared electroluminescence at room temperature from neodymium-doped gallium nitride thin films. United States. doi:10.1063/1.1781745.
Kim, Joo Han, Holloway, Paul H., and Department of Materials Science and Engineering, University of Florida, Gainesville, Florida 32611-6400 and MICROFABRITECH, University of Florida, Gainesville, Florida 32608. 2004. "Near-infrared electroluminescence at room temperature from neodymium-doped gallium nitride thin films". United States. doi:10.1063/1.1781745.
@article{osti_20632770,
title = {Near-infrared electroluminescence at room temperature from neodymium-doped gallium nitride thin films},
author = {Kim, Joo Han and Holloway, Paul H. and Department of Materials Science and Engineering, University of Florida, Gainesville, Florida 32611-6400 and MICROFABRITECH, University of Florida, Gainesville, Florida 32608},
abstractNote = {Strong near-infrared (NIR) electroluminescence (EL) at room temperature from neodymium (Nd)-doped gallium nitride (GaN) thin films is reported. The Nd-doped GaN films were grown by radio-frequency planar magnetron cosputtering of separate GaN and metallic Nd targets in a pure nitrogen ambient. X-ray diffraction data did not identify the presence of any secondary phases and revealed that the Nd-doped GaN films had a highly textured wurtzite crystal structure with the c-axis normal to the surface of the film. The EL devices were fabricated with a thin-film multilayered structure of Al/Nd-doped GaN/Al{sub 2}O{sub 3}-TiO{sub 2}/indium-tin oxide and tested at room temperate. Three distinct NIR EL emission peaks were observed from the devices at 905, 1082, and 1364 nm, arising from the radiative relaxation of the {sup 4}F{sub 3sol2} excited-state energy level to the {sup 4}I{sub 9sol2}, {sup 4}I{sub 11sol2}, and {sup 4}I{sub 13sol2} levels of the Nd{sup 3+} ion, respectively. The threshold voltage for all the three emission peaks was {approx}150 V. The external power efficiency of the fabricated EL devices was {approx}1x10{sup -5} measured at 40 V above the threshold voltage.},
doi = {10.1063/1.1781745},
journal = {Applied Physics Letters},
number = 10,
volume = 85,
place = {United States},
year = 2004,
month = 9
}
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