“…50,51 The interaction between Fe atoms and Si produces a number of stable ͓Fe 3 Si, 6,21,26,27,45 -FeSi, [5][6][7]9,12,20,21,25,45 and -FeSi 2 ͑Refs. 5-7, 9, 12, 20, 21, 25, and 45͔͒ and metastable silicides ͑FeSi with the CsCl-type of structure, 9,18,20,21,25,27,29,40,45 ␥-FeSi 2 with the CaF 2 structure, [5][6][7]10,11,16,18,29,40,44 ␣-FeSi 2 at temperatures below 920°C, 16,17,19,24,38,45 etc.͒. The formation of metastable silicides is due to the fact that their lattice mismatch with the Si substrate is much smaller than that for stable silicides.…”