| Autor: |
U.S. Sias, Eduardo Ceretta Moreira, Henri Ivanov Boudinov, L. Amaral, Moni Behar |
| Rok vydání: |
2006 |
| Předmět: |
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| Zdroj: |
Nuclear Instruments and Methods in Physics Research Section B: Beam Interactions with Materials and Atoms. 250:178-182 |
| ISSN: |
0168-583X |
| DOI: |
10.1016/j.nimb.2006.04.104 |
| Popis: |
In the present work we have studied the photoluminescence (PL) behavior from Si nanocrystals (NCs) as a function of the excitation power density and annealing time. The NCs were produced in a SiO2 matrix by Si implantations from room temperature (RT) up to 700 °C, followed by post-annealing in N2 atmosphere at high temperature. With this aim we have changed the excitation power density (from 2 × 10−3 W/cm2 up to 15 W/cm2) and the annealing time (from 10 min up to 15 h). The strong PL signal, which at 15 W/cm2 is composed by a single-peak structure (650–1000 nm) centered at around 780 nm, expands up to 1200 nm showing a two-peak structure when measured at 20 × 10−3 W/cm2. The peak structure located at the short wavelength side is kept at ∼780 nm, while the second peak, starting at around 900 nm, redshifts and increases its intensity with the implantation temperature and annealing time. The effect of the annealing time on the PL spectra behavior measured at low excitation power agrees by the first time with the Si NC growth according to quantum confinement effects. |
| Databáze: |
OpenAIRE |
| Externí odkaz: |
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