Towards the structure of rare earth luminescence centres _ terbium doped aluminium nitride as an example system

18th Microscopy of Semiconducting Materials Conference

物理学;材料科学

Benz, Felix^1 ; Walther, Thomas^2 ; Strunk, Horst P.^1

Institute of Materials Science, University of Stuttgart, Heisenbergstr. 3, 70569 Stuttgart, Germany^1

Kroto Centre for High Resolution Imaging and Spectroscopy, Department Electronic and Eletrical Eng., University of Sheffield, Mappin Street, Sheffield S1 3JD, United Kingdom^2

关键词: Crystal-field splitting;    Ionic compounds;    Lattice positions;    Oxygen ions;    Random distribution;    Rare earth luminescence;    Semi-empirical calculation;    Terbium ions;   

Others  :  https://iopscience.iop.org/article/10.1088/1742-6596/471/1/012032/pdf
DOI  :  10.1088/1742-6596/471/1/012032

学科分类：材料科学（综合）

来源: IOP

【 摘 要 】

Sputter deposited terbium doped aluminium nitride layers were investigated with respect to the distribution and surroundings of the terbium luminescence ions. Semi-empirical calculations indicate that terbium forms complexes consisting of one aluminium vacancy surrounded by three oxygen ions on nitrogen lattice positions and one nitrogen ion that is bound to a terbium ion on a distorted aluminium lattice position. The crystal field splitting of the terbium ions indicate their surroundings to be not tetrahedral but, as anticipated from the determined complex, C3v. Complementary electron microscopic investigations show a random distribution of these complexes within the layer volume. The terbium ions cause a shape of the Tb M5,4edge similar to the shapes in other ionic compounds like Tb2O3.