Influence of film thickness and annealing temperature in growth of Mg2Si thin films.

In this work we examine the influence of film thickness and annealing temperature in the growth of Mg2Si thin films. Films were grown by dual cathode magnetron sputtering (DCMS) at room temperature. Two series of films were grown, one with thickness about 0.96μm (films-A) and another with (1.99μm) (films-B). Sputtered films were subsequently annealed in Ar gas atmosphere at temperatures 250°C, 300°C (films-B) and 380°C, 500°C (films-A). Results indicate that growth in films-A proceeds with the formation of two phases, a cubic (Fm-3m) and a strained (compressed) cubic with smaller lattice constant. When film thickness is doubled (films-B) material transforms into unstrained cubic phase. Annealing films-B at 300°C transforms them into the same compressed cubic phase that was observed in films-A. Further annealing of films-A causes a strain relief and at 500°C films are single phase. [ABSTRACT FROM AUTHOR]