Iron disilicide formation by Au-Si eutectic reaction on Si substrate

We have investigated the growth of iron disilicide on Au-coated Si(0 0 1) substrates and its photoluminescence behaviour. X-ray diffraction, scanning electron microscopy, and transmission electron microscopy observations revealed that the Si surface above 380 °C was melted as a result of the Au-Si eutectic reaction and that coarse island disilicide grains with sizes of several micrometres were formed on the Si surface. The full width at half maximum of 0.056° on the rocking curve of α-FeSi₂004 was observed on the sample deposited at 800 °C, and indicated the high crystal quality in perfection of orientation. The photoluminescence spectrum of β-FeSi₂ grains, which were deposited at 750 °C, was observed. The melted Si surface contributed to the improved crystallinity of α-FeSi₂ and β-FeSi₂.