Both the single crystalline Si and Er targets are ablated alternately by XeCl excimer laser (wavelength 308 nm) to fabricate Er-doped amorphous Si films on Si and quartz substrates in the vacuum chamber at the pressure of 2×10-4 Pa, and the concentration of Er-doping can be controlled through laser pulse ratio on both Si and Er targets. The samples are subsequently annealed for 30 min in flowing nitrogen. The scanning electron microscope (SEM) images of the samples indicate that more uniform nc-Si films could be achieved at lower annealing temperature by choosing reasonable Er-doping concentration comparing to un-doped samples; The Raman spectra show that Er-doping is valid for the growing of the nanoparticles, but decreases the crystalline degree of the samples at the same annealing temperature. Higher annealing temperature is needed for crystalline of Er-doped amorphous Si films than the amorphous Si films.