Atomic structure of luminescent centers in high-efficiency Ce-doped w-AlN single crystal.
Rare-earth doped wurtzite-type aluminum nitride (w-AlN) has great potential for high-efficiency electroluminescent applications over a wide wavelength range. However, because of their large atomic size, it has been difficult to stably dope individual rare-earth atoms into the w-AlN host lattice. Here we use a reactive flux method under high pressure and high temperature to obtain cerium (Ce) doped w-AlN single crystals with pink-colored luminescence. In order to elucidate the atomic structure of the luminescent centers, we directly observe individual Ce dopants in w-AlN using annular dark-field scanning transmission electron microscopy. We find that Ce is incorporated as single, isolated atoms inside the w-AlN lattice occupying Al substitutional sites. This new synthesis method represents a new alternative strategy for doping size-mismatched functional atoms into wide band-gap materials.
Materials Science and Technology Division, Oak Ridge National Laboratory, Oak Ridge, TN 37831, USA.
Ryo
R
Ishikawa
Materials Science and Technology Division, Oak Ridge National Laboratory, Oak Ridge, TN 37831, USA.
Andrew R
AR
Lupini
1] Department of Materials Science and Engineering, Kyoto University, Sakyo, Kyoto 606-8501, Japan [2] Materials Research Center for Element Strategy, Tokyo Institute of Technology, Yokohama 226-8503, Japan.
Fumiyasu
F
Oba
School of Physics, Monash University, Victoria 3800, Australia.
Scott D
SD
Findlay
1] Institute of Engineering Innovation, University of Tokyo, Bunkyo, Tokyo 113-8656, Japan [2] Japan Science and Technology Agency, PRESTO, Kawaguchi, Saitama 332-0012, Japan.
Naoya
N
Shibata
Advanced Key Technologies Division, National Institute for Materials Science, Tsukuba, Ibaraki 305-0044, Japan.
Takashi
T
Taniguchi
Advanced Key Technologies Division, National Institute for Materials Science, Tsukuba, Ibaraki 305-0044, Japan.
Kenji
K
Watanabe
Department of Materials Science and Engineering, Kyoto University, Sakyo, Kyoto 606-8501, Japan.
Hiroyuki
H
Hayashi
Department of Materials Science and Engineering, Kyoto University, Sakyo, Kyoto 606-8501, Japan.
Toshifumi
T
Sakai
1] Department of Materials Science and Engineering, Kyoto University, Sakyo, Kyoto 606-8501, Japan [2] Nanostructures Research Laboratory, Japan Fine Ceramics Center, Atsuta, Nagoya 456-8587, Japan.
Isao
I
Tanaka
1] Institute of Engineering Innovation, University of Tokyo, Bunkyo, Tokyo 113-8656, Japan [2] Nanostructures Research Laboratory, Japan Fine Ceramics Center, Atsuta, Nagoya 456-8587, Japan.
Yuichi
Y
Ikuhara
Materials Science and Technology Division, Oak Ridge National Laboratory, Oak Ridge, TN 37831, USA.
Stephen J
SJ
Pennycook
D017607:Aluminum Compounds / Q000737:chemistry*; D002563:Cerium / Q000737:chemistry*; D003460:Crystallization; D049449:Luminescence; D010316:Particle Size
D017607:Aluminum Compounds; D002563:Cerium; C052045:aluminum nitride