Papers by Keyword: Temperature Quenching

Abstract: The La_1‑xEu_xVO₄ powders were synthesized by co-precipitation method. Emission spectra of the LaEuVO₄ and La_1‑xEu_xVO₄ powders consist of wide non-structural bands of the matrix emission and narrow spectral lines caused by inner f-f electron transitions in the Eu³⁺ ions, respectively. The both types of emission were studied within 8 – 300 K temperature range. Decomposition of spectra of the wide matrix emission on three bands has been carried out and temperature dependencies for each band were studied. Temperature behavior of the Eu³⁺ emission was investigated for lines assigned to different Eu³⁺ centres. Obtained dependencies are analyzed and discussed using proposed schemes of transitions in the VO₄^3- groups and structure of the nearest surrounding of the Eu³⁺ emission centres.

Abstract: The temperature quenching mechanisms of the electroluminescence (EL) and the reactivation of the rare earth luminescent centres by the flash lamp annealing (FLA) made after hot electron injection into the SiO2 layer implanted by Tb and Gd was investigated. An increase of the temperature from room temperature up to 150oC reduces the gate voltage of about 3 V and increases the rate of the EL quenching process and the degradation of the Metal-Oxide-Silicon Light Emitting Diode (MOSLED) structure by a of factor of three. On the other hand, the post-injection FLA reactivates the RE centres switched off by electrons trapped around them during hot electron impact excitation, increasing the operating time of the MOSLEDs devices.