Hydrogenated amorphous silicon (a-Si:H) films were prepared by sputtering a Si target in an atmosphere of Ar+H2. The Er (and Er+Yb) doping of the films was achieved by partially covering the Si target with small pieces of Er (Er+Yb) metal. After deposition the films were annealed up to 700 °C in an inert atmosphere. Ion beam analyses, Raman spectroscopy, optical transmission and photoluminescence measurements were employed for characterization purposes. According to the experimental results, thermal treatments up to ∼300 °C do not significantly alter the composition, atomic structure or optical bandgap of the present a-Si:H films. On the contrary, the Er-related photoluminescence intensity at 1540 nm increases and reaches its maximum at about 400 °C. Treatments at temperatures higher than ∼400 °C reduce both the Er-related light emission and the optical bandgap of the films due to the out-diffusion of hydrogen atoms. Furthermore, the relatively small optical bandgap and the presence of tail states prevent any optical activity of Yb3+ ions in the measured a-Si:H films. At the present doping levels and sample characteristics, ytterbium only increases the incidence of non-radiative processes.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.