Thermally stimulated exo-electron emission and desorption from Lu2O3:Eu3+ surfaces

• Published in: Optical materials Vol. 137; p. 113556
• Main Authors: Pokorný, P., Novotný, M., Fitl, P., Dekhtyar, Y., More-Chevalier, J., Chertopalov, S., Remsa, J., Irimiciuc, S., Vrňata, M., Lančok, J.
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 01-03-2023
• Subjects: Pulsed laser annealing; Pulsed laser deposition; Sensors; Thermostimulated desorption; Thermostimulated exo-electron emission; Thin films; Pulsed laser annealing; Thin films; Thermostimulated desorption; Pulsed laser deposition; Thermostimulated exo-electron emission; Sensors
• ISSN: 0925-3467; 1873-1252
• DOI: 10.1016/j.optmat.2023.113556

Thermally stimulated exo-electron emission (TSEE) and thermally stimulated desorption (TSD) methods were employed to characterize interactions in the surface of thin films of Lu2O3 doped by Eu3+ fabricated by pulsed laser deposition. Samples with 1 and 3% doped europium were selected. Pulsed laser annealing (PLA) was performed to modify surfaces. TSEE maxima are shown at temperature ranges T ∼120, 270 °C and T ∼250, 350 °C for 1 and 3% europium content, respectively. The TSEE maxima correspond with TSD maxima of LuO and EuO observed at higher temperatures. At lower temperatures the release of atomic oxygen Oat and OH radicals is taking place at the points, edges, and other imperfections of the crystals. The presence of Eu3+ contributes to the incipient material decomposition in dependence on Eu concentration. Desorption of individual atoms and radicals (Oat, OH, Lu, Eu, LuO, and EuO) during decomposition into components reveals a coincidence with the emission of negative ions. This can be explained by the fact that electrons are simultaneously emitted when particles are released. Activation energy and frequency factors were calculated to precise description of the surface processes.
•Simultaneous TSEE and TSD measurements of Lu2O3:Eu3+ (1% and 3%) thin films.•TSEE maxima at temperatures T ∼ 120, 270 °C and T ∼ 250, 350 °C for 1% and 3% resp.•Pulsed laser annealing performed to modify film surfaces.•TSEE maxima correspond with TSD maxima of LuO and EuO.•Desorption of Oat, OH, Lu, Eu, LuO and EuO during film decomposition coincidences with negative ions emission.