In this project the photoluminescence (PL) of silicon nanocrystals is studied. It is found that the PL spectrum consists of a band-to-band component and a defect related component. A linear dependence between the excitation energy and the intensity of the defect related component is found. The fraction of excited crystals was kept constant by altering the laser beam intensity. The defect related energy level is probably introduced by oxygen bonds at the edge of the nanocrystal, and possibly lies inside the conduction band. A systematic method of measurement is proposed for future characterization of silicon nanocrystals.
University of Amsterdam, Faculty of Science, Van der Waals-Zeeman Institute