High intensity red emission from Eu doped GaN powders

Abstract

Eu doped GaN powders have been produced by a low‐cost and high‐yield method. The effect of temperature on the optical properties and structure was investigated by photoluminescence, X‐ray diffraction and Raman spectroscopy. The effective Eu incorporation was extracted by a non‐destructive strain analysis correlating the Raman with the XRD data. Luminescence intensity was closely related to the effective Eu incorporation. The maximum Eu incorporation was determined to be 0.5 at% for the sample grown at 1000 °C, which showed the strongest red photoluminescence with the highest crystallinity. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)

Crystal field and Zeeman parameters of substitutional Yb3+ ion in GaN

“…The high thermal conductivity, chemical and thermal stability, refractive index, breakdown dielectric strength and wide band gaps of GaN, AlN and their alloys create opportunities to explore the spectral characteristics of RE 3+ ions in a wide spectral range. It was shown recently that efficient phosphors [1][2][3], optically stimulated laser action [4] and electrically excited p-n junction light emitting diode [5] are feasible using these materials. Despite of these recent technological advances the electronic structure of the RE luminescence centers, as well as their indirect excitation mechanism are still not well understood.…”

Schottky barrier formation at the Au to rare earth doped GaN thin film interface

“…Moreover, the tunable band gaps of these III-nitride alloys offer device applications across the visible spectrum through the ultraviolet range, to include optically stimulated lasing [5] and p-n junction light-emitting diodes in the red [6] using lanthanide-doped AlN and GaN, as well as in the blue. Lastly, the production of thin film electroluminescent phosphors with red, blue, and green emissions [7][8][9] offers the promise of full color (white) light capability.…”

Resonant photoemission of rare earth doped GaN thin films

“…III-nitride semiconductors, such as AlN, GaN, and InN, offer tunable bandgaps and favorable thermal, chemical, and electronic properties, which facilitate various device applications [5][6][7][8][9] from the ultraviolet through the visible spectrum to the infrared range. Moreover, thin film electroluminescent phosphors with red, blue, and green emissions [7][8][9][10][11][12][13][14][15] imply the promise of full color (white) light capability. Rare earth doping GaN might have a number of advantages: there is the promise that Eu or Er doping will improve the light output.…”

“…Although likely to locally strain the lattice, the 4f rare earths will tend to adopt substitutional sites for Ga [1, 2,26] in GaN while significantly altering magnetic [27][28][29][30][31][32][33][34] and optical properties [7][8][9][10][11][12][13][14], and it is therefore of considerable interest to know whether even low concentrations of a rare earth in the GaN host can alter the surface electronic structure. This is likely, as although rare earths are isoelectronic with Ga 3+ , they may be associated with other defects [35,36].…”