Electroluminescence Spectra

Abstract

The electroluminescence spectra obtained from RE-implanted MOSLEDs are basically a result of an electronic transition within the 4f shell of a trivalent RE ion after an electrical excitation by hot electrons. The optical spectra of REs, mostly obtained by PL or absorption measurements, have been widely investigated for decades, especially in crystalline host materials like LaCl3 or Y2O3, and there are a couple of excellent surveys about this topic [233–238]. Therefore, only a brief introduction concerning the physics of 4f intrashell transitions is given in Sect. 4.1.1, as these explanations can be found in greater detail in most of the textbooks devoted to quantum mechanics and the literature mentioned above. In the following, the EL properties of RE-implantedMOSLEDs are shown and discussed on the basis of own results. While the Sects. 4.1.2–4.1.4 deal with the used experimental techniques, with the EL spectra of unimplanted and with that of RE-implanted MOSLEDs, the subsequent chapters cover the dependence of the EL spectrum on the operation and fabrication conditions. In detail, the focus is set on the injection current dependence (Sect. 4.2), the concentration quenching (Sect. 4.3) and the annealing behaviour (Sect. 4.4).