ELABORATION AND TESTING OF MATERIALS USING CONCENTRATED SOLAR ENERGY
1. Brief history of the use of solar energy to transform matter 2. Main characteristics of solar furnaces 3. Elaboration of materials using concentrated solar energy 3.1 Surface treatments 3.2 Melting and purification of bulk materials 3.3 Production of chemical commodities and ceramics 3.4 Elaboration of carbon molecules, nanomaterials and thin films 4. Testing of materials using concentrated solar energy 4.1 Original devices at the focus of solar furnaces 4.2 Test of materials for aerospace applications 4.2.1 Atmopsheric re-entry (oxidation and catalycity) 4.2.2 Solar probe mission 4.3 Test of materials for future system of energy production 5. Conclusion Bibliography Biographical Sketches
Purification of metallurgical grade silicon by a solar process
The purification of upgraded metallurgical silicon by extraction of boron and phosphorus was experimentally demonstrated using concentrated solar radiation in the temperature range 1550–1700 1C. The process operated with a flow of Ar at reduced pressure (0.05 atm) for elimination of P, and with a flow of H2O for elimination of B. Impurity content decreased by a factor of 3 after a 50-min solar treatment, yielding Si samples with final average content of 2.1 ppmw B and 3.2 ppmw P. r 2006 Elsevier B.V. All rights reserved.
Anomalous Annealing Behavior of Arsenic Implanted Silicon as a Function of Dose and Energy
Anomalous annealing behavior of damage in As implanted Si has been investigated by channeling effect measurements. Room temperature As implants with doses from 1014 to 2 × 1016cm-2 at energies ranging from 50 to 250 keV into Si were annealed over the range of 600°C to 1100°C. Anneal temperatures ≥ 950°C reduce the disorder for ion doses of 0.5 to 1 × 1016 cm-2 at energies between 50 and 250 keV. Anomalously high residual disorder was found for the intermediate doses of 2 × 1014 to 2 × 10/cm2 implanted above 100 keV. For this intermediate dose, annealing of implants performed at liquid nitrogen temperatures did not show significant reduction in this damage. However implants at 200° to 300°C indicate a lower amount of damage compared to the room temperature implants.