Effects of La doping on Mg2Si semiconductor thin films prepared by thermal evaporation

La doped Mg2Si semiconductor thin films were prepared on n-Si (111) substrate by thermal evaporation. The structure, morphology and optical properties of La doped Mg2Si thin films were investigated by x-ray diffractometer (XRD), field-emission scanning electron microscopy (FESEM) and Raman spectrometer (RAMAN). XRD results show that after doping La, the Mg2Si diffraction peak decreases and shifts to a low angle, and the lattice constant increases. FESEM results show that after doping La, the size of Mg2Si crystallite decreases and the crystallites aggregate into clusters. RAMAN results show that the intensity of characteristic Raman peaks near 256 and 690 cm(-1) decreases after incorporation of La.