Cr3+ Impurities and Photoluminescence in LaAlO3
Cr3+ Impurities and Photoluminescence in LaAlO3
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LaAlO3 中的 Cr3 杂质和光致发光
DOI：
10.1143/jjap.49.091102
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发表时间：
2010
影响因子：
1.5
通讯作者：
Y. Ohki
中科院分区：
文献类型：
--
作者：
E. Hirata;K. Tamagawa;Y. Ohki
测量了两种类型样品的紫外（UV）光子在LaAlO 3中诱导的光致发光（PL）光谱，单晶片和薄膜。沉积时为非晶的膜在800 °C或更高温度下退火后变成多晶。当激发光子能量超过LaAlO 3的带隙能量时，在Si单晶衬底上沉积和退火的单晶和多晶薄膜中出现了三个PL峰，其位置约为1.60 eV。当薄膜沉积在CaF 2单晶衬底上并退火时，面内晶格参数变小，三个PL峰的能量向高值移动。这表明三个PL峰对晶体场敏感。此外，三个PL峰的强度不依赖于测量温度。考虑到这些结果连同它们的光谱形状，三个PL峰是由于R线发光导致的Cr 3+杂质在LaAlO 3。电感耦合等离子体发射光谱法检测Cr 3+离子失败，表明本样品中Cr 3+含量低于1 ppm。用不同原料和不同工艺制备的单晶片和薄膜均出现PL峰，说明Al矿石中存在Cr ~（3+）离子的可能性很大。另一个PL峰出现在2.8 eV的单晶被认为是源于氧空位。
Photoluminescence (PL) spectra induced in LaAlO3 by ultraviolet (UV) photons were measured for two types of samples, i.e., single-crystal plates and thin films. The films, which were amorphous when deposited, became polycrystalline after being annealed at 800 °C or higher. When the excitation photon energy exceeded the band-gap energy of LaAlO3, three PL peaks appeared at approximately 1.60 eV in the single crystals and polycrystalline films deposited and annealed on a Si single-crystal substrate. When the films were deposited and annealed on a CaF2 single-crystal substrate, the in-plane lattice parameters became smaller and the energies of the three PL peaks shifted to higher values. This indicates that the three PL peaks are susceptible to a crystal field. Furthermore, the intensities of the three PL peaks did not depend on the measurement temperature. Taking these results together with their spectral shapes into consideration, the three PL peaks are due to the R-line luminescence resulting from Cr3+ impurities in LaAlO3. The detection of Cr3+ ions by inductively coupled plasma optical emission spectrometry failed, indicating that the Cr3+ content of the present samples is below 1 ppm. The fact that the PL peaks appeared in both the single-crystal plates and thin films obtained from different raw chemicals with different processes indicates that there is a strong possibility that the Cr3+ ions are present in Al ore. Another PL peak appearing at 2.8 eV in the single crystals was assumed to originate from oxygen vacancies.
影响因子：
3.2
作者：
Toshihide Ito;M. Maeda;Kazuhiko Nakamura;H. Kato;Y. Ohki
通讯作者：
Toshihide Ito;M. Maeda;Kazuhiko Nakamura;H. Kato;Y. Ohki
紫外光子诱导硅酸铪和硅酸锆的几个光致发光带的机制
DOI：
--
发表时间：
2006
期刊：
J. Appl. Phys 99
影响因子：
--
作者：
T.Ito;H.Kato;Y.Ohki
通讯作者：
Y.Ohki