Correlation between structural and optical properties of ion beam synthesized beta-FeSi2 precipitates in Si.

Grimaldi M. G., Coffa S., Spinella C., Marabelli F., Galli M., Miglio L., Meregalli V.

Univ Catania Ist Nazl Fis Mat Corso Italia 57 I-95129 Catania Italy
Univ Catania Dipartimento Fis I-95129 Catania Italy
Cnr Ist Nazl Metodol & Tecnol Microelettron I-95121 Catania Italy
Univ Pavia Ist Nazl Fis Mat I-27100 Pavia Italy
Univ Pavia Dipartimento Fis A Volta I-27100 Pavia Italy
Univ Pavia Ist Nazl Fis Mat I-20126 Milan Italy
Univ Pavia Dipartimento Sci Mat I-20126 Milan Italy
Mpi Fkf D-70569 Stuttgart Germany

The structural and optical properties of beta-FeSi2 precipitates produced by ion beam synthesis have been investigated by transmission electron microscopy, photoluminescence (PL) analysis and near infrared transmission measurements. The PL spectrum of beta-FeSi2 precipitates in a dislocation free sample has been observed to consist of a sharp line at 1.54 mu m and a weak peak at 1.46 mu m. Optical transmission measurements showed a direct band gap about 0.8 eV, smaller than in continuous beta-FeSi2 film. Calculation of the electronic bands of beta-FeSi2 for different values of the lattice parameters indicates that this reduction can be ascribed to band distortion provided by the lattice strain.
© Copyright 1999 Elsevier Science B.V. All rights reserved.

Journal of Luminescence, 80 467-471, 1998.

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