We have investigated the growth of iron disilicide on Au-coated Si(001) substrates and its photoluminescence behaviour. X-ray diffraction, scanning electron microscopy, and transmission electron microscopy observations revealed that the Si surface above 380 degrees 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 degrees on the rocking curve of alpha-FeSi2 004 was observed on the sample deposited at 800 degrees C, and indicated the high crystal quality in perfection of orientation. The photoluminescence spectrum of beta-FeSi2 grains, which were deposited at 750 degrees C, was observed. The melted Si surface contributed to the improved crystallinity of alpha-FeSi2 and beta-FeSi2. (C) 2009 Elsevier B. V. All rights reserved.