Yb3+-related photoluminescence is observed at room temperature from Yb-doped porous silicon layers prepared by the electro-chemical method developed by our group for Er doping of porous silicon layers. After rapid thermal annealing in a pure argon atmosphere at high temperatures (above ∼ 900°C), samples show a sharp photoluminescence band at around 1.0 μm which is assigned to the intrashell 4f-4f transitions 2F 5/2 → 2F7/2 of Yb3+. The enlarged energy bandgap of silicon as a result of anodization makes possible the excitation of Yb3+ 4f-electrons with the recombination energy of photocarriers generated in the host porous silicon layers.
ASJC Scopus subject areas
- Physics and Astronomy (miscellaneous)