HIGH CRYSTALLINE QUALITY ERBIUM SILICIDE FILMS ON (100)SILICON, GROWNIN HIGH-VACUUM

Erbium silicide films were grown in high vacuum (10(-8) Torr) on (100) silicon substrates by erbium evaporation on a heated substrate and su bsequent annealing, The substrate temperature was between 400-450 degr ees C and a second annealing step was given at 800-870 degrees C for 3 0 min. Films with a thickness in the range of 40-50 nm were prepared. X-ray and electron diffraction were used for the characterisation of t he grown films. Transmission electron microscopy characterisation reve aled the very high crystalline quality of the films. They were almost single crystalline, of very large 'grains', up to a few hundreds of nm , slightly misoriented with respect to each other, The erbium silicide was found to possess a modulated structure, derived from a basic one of the ThSi2 type.