Influence of sputtering power on the structural and morphological properties of semiconducting Mg2Si films

Mg2Si films have been prepared by magnetron sputter deposition and thermal process. Metal Mg films of about 380 nm thickness were deposited first on Si (111) substrates by radio frequency (RF) magnetron sputtering at various sputtering powers, and subsequent annealing was performed in an argon atmosphere. The formation of Mg2Si films was clarified using X-ray diffraction (XRD), and the surface microstructure of the prepared Mg2Si films was characterized by scanning electron microscopy (SEM). The results showed that the strongest diffraction peaks of all the Mg2Si films prepared on Si (111) substrates were observed at 40.12°. When the RF sputtering power increased, there was a significant increase in the intensity of the diffraction peak. However, increasing the sputtering power further to 110W failed to yield further improvement in the intensity of the different peak. The optimal sputtering power is 100W for the preparation of the Mg2Si films under the present preparation conditions. SEM results indicted that the grain sizes increased with the increasing of the sputtering power.