Ion beam synthesis of Mg2Si

The semiconducting metal silicides and Mg2Si in particular have been extensively studied in the last few years because of the following reasons: the materials have the potential to be successfully integrated in the optoelectronic silicon technology, the materials are nontoxic and the constituting elements are found in a large amount in nature, and lastly the formation of nanocrystals in a perticular matrix offers the possibility of semiconducting structures with new properties. The Mg-Si phase diagram shows that Mg2Si is the only silicide in this system and it melts congruently at 1085DGC. Therefore, crystal growth from the melt should be possible, but one has to be careful about the considerable evaporation of the Mg component as the boiling point of pure Mg is very close to the compound melting temperature. Growth by chemical vapor transport is hardly possible because of the lack of stable magnesium halides and the growth of Mg2Si bulk material has been accomplished exclusively from a melt.