Epitaxial growth of ErSi2 on (111) Si

The epitaxial growth of ErSi2 is described. In this study, erbium metal is evaporated onto Si(111) and annealed to form erbium silicide, where the pressure during all procedures is maintained below 5 × 10−10 Torr. The interdiffusion of erbium with silicon occurs as low as 300°C, as determined by in situ Auger electron spectroscopy. Low energy electron diffraction shows the 3×3 pattern of the hexagonal silicide, with evidence of surface faceting. Both X-ray and Rutherford backscattering analyses indicate single-crystal growth with a channeling minimum yield of 2%–3% for silicide films of 200–400-Å thickness annealed to 800–900°C. The surface morphology of these films is smooth but pitted with an average pinhole size of less than 1 microm. These results support growth models based on nucleation reaction mechanisms and not those based on interfacial contamination effects. Electrical measurements show metallic conduction with a room temperature resistivity of 35micro ohm cm.