Citation
Avella Romero, Manuel and Prieto Colorado, Ángel Carmelo and Rodríguez Domínguez, Andrés and Sangrador García, Jesús and Rodríguez Rodríguez, Tomás and Ortiz Esteban, María Isabel and Ballesteros Pérez, Carmen Inés
(2008).
Influence of the crystallization process on the luminescence of multilayers of SiGe nanocrystals embedded in SiO2.
"Materials Science and Engineering B", v. 147
(n. 2-3);
pp. 200-204.
ISSN 0921-5107.
https://doi.org/10.1016/j.mseb.2007.08.016.
Abstract
Multilayers of SiGe nanocrystals embedded in an oxide matrix have been fabricated by low-pressure chemical vapor deposition SiO2 onto Si wafers (in a single run at 390 ◦C and 50mTorr, using GeH4, Si2 H6 and O2) followed by a rapid thermal annealing crystallize the SiGe nanoparticles. The main emission band is located at 400 nm in both cathodoluminescence and photoluminescence at 80K and also at room temperature. The annealing conditions (temperatures ranging from 700 to 1000 ◦C and for times of 30 investigated in samples with different diameter of the nanoparticles (from ≈3 to ≥5 nm) and oxide interlayer thickness (15 and establish a correlation between the crystallization of the nanoparticles, the degradation of their composition by Ge diffusion the luminescence emission band. Structures with small nanoparticles (3–4.5 nm) separated by thick oxide barriers (≈35 nm) annealed 60 s yield the maximum intensity of the luminescence. An additional treatment at 450 ◦C in forming gas for dangling-bond the intensity of the luminescence band by 25–30%.
