Growth and Characterization of Thermoelectric Mg₂Si Thin Films

Abstract

In this work, room temperature co-deposition of Mg and Si was used to successfully fabricate Mg 2 Si thin films on Si substrate by dual cathode magnetron sputtering (DCMS). Films were annealed at 380°C. Various Mg/Si sputtering power ratios have been examined. XRD, SEM and IR reflectivity measurements on grown and annealed films, reveal that annealing is enhancing the formation of crystalline Mg 2 Si.

Formation of Mg₂Si/MgO Nano-Composites Prepared by Dual Cathode Magnetron Sputtering

“…In Figure 7 are presented the infrared (IR) reflectivity spectra of the annealed films in the frequency region 100-700 cm -1 . The as-grown films do not present any of the characteristic peaks of Mg 2 Si [13]. On the contrary, the annealed samples present the two characteristic bands of crystalline Mg 2 Si.…”

“…As-grown films are homogeneous, compact and smooth without any surface texture [12,13]. When films are annealed in 380°C, surface texture appears with bumps, which become denser as Mg sputtering power is increased [13]. Figure 5 shows typical SEM micrographs for films annealed at 500°C.…”

“…In previous work, Mg 2 Si thin films were successfully grown with dual cathode magnetron sputtering (DCMS) on Si substrate at room temperature with high [12] or low Mg sputtering powers [13]. In this work DCMS method has been used to grow Mg 2 Si thin films on Si substrate and the effect of annealing is examined on the formation of Mg 2 Si/MgO nano-composites.…”