Preparation of epitaxial Ge film on Si by pulsed laser ablation using molten droplets

Ge films were prepared by pulsed laser ablation (PLA) using molten droplets on (100) Si substrates. The second harmonic of YAG laser (532 nm) was empl oyed for producing the Ge droplets. The Ge film prepared at room temperatur e was found to have a large number of solidified droplets on the substrate indicating that the present PLA process is mainly governed by droplet eject ion from the target. The X-ray pole-figure measurement for Ge film prepared at an elevated substrate temperature revealed that the film has Ge crystal s aligned in plane as well as out of plane in a cube-on-cube manner. These results indicate an epitaxial growth of Ge film on Si by PLA using a large number of molten droplets.