Studies of swift iron ions in crystalline silicon

P-type silicon samples were irradiated with 56Fe7+ ions for different ion fluences varying from 1 × 1013 to 5 × 1014 cm− 2 at 100 MeV. Atomic force microscopy study showed the group of nanoclusters on the surface of <111> silicon. The size, shape and diameter of the nanoclusters are found to be strongly influenced by ion fluence. Three dimensional atomic force microscopy images of the samples irradiated with different ion fluences showed hillocks surrounded with valleys. Grazing angle X-ray diffraction study revealed the formation of different phases of FeSi2 depending on ion fluences. The interference fringes observed in the Fourier transform infrared studies revealed the presence of FeSi2 layer with a thickness comparable to ion range. The decay of the fringe amplitudes with wave number indicates non constant dielectric constants.