Iron silicide nanostructures were grown on Si(001) by strain-induced, self-assembly method. E-gun evaporated iron particles were deposited both onto room temperature and high temperature Si substrates, and were further annealed in situ. The initial Fe thickness was in the 0.1-6 nm range and the annealing temperatures varied between 500 and 850°C. The phases and structures formed were characterized by reflection high energy electron diffraction and by scanning electron microscopy. The electrical characteristics were investigated by I-V and C-V measurements, and by deep level transient spectroscopy. The size distributions of the formed iron silicide nanostructures were not homogeneous but, were oriented in perpendicular directions on Si(001). Higher temperature annealing resulted in increased particles size and faceting. Electrical characteristics showed critical defect concentration related to Fe.