THE INFLUENCE OF GERMANIUM SUBSTITUTION ON THE PHASE-STABILITY OF 3D TRANSITION-METAL DISILICIDES

Few studies have been up to now devoted to the metallization of Si-Ge alloys and most of them concerns the sequence of phases formation for thin films interactions. In order to obtain a better understanding of these metallization processes, we have determined the thermodynamic equilibrium state by a systematic analysis of the ternary phase diagrams in the region of interest, which is the quasi-binary between the non-metal richest phases in both M-Si and M-Ge systems. The results show that as a function of the number of d electrons of the 3d metal, three different situations can be found: total miscibility (Ti), partial miscibility (V, Fe) or immiscibility (Cr, Mn, Fe, Co). These results can then be used to analyse and in some cases to predict the phase formation during the interaction of a 3d metal with a Si-Ge thin film.