CRYSTALLIZATION OF AMORPHOUS ANTIMONY LAYERS ON AS-DEPOSITED ULTRATHIN SUBLAYERS OF SILVER

We have directly observed, by optical microscopy, the crystallization process of an amorphous antimony layer 3.4-8.9 nm thick prepared on an as-deposited layer of silver whose thickness ranges from 0.7×10-2 to 8.5×10-2 nm. A whole specimen is deposited onto a cover glass in a vacuum of 3×10-4 Pa. The averaged growth rate ν of crystallites nucleated in the amorphous antimony layer is measured as a function of the reciprocal thickness dSb-1of the antimony layer and also as a function of the substrate temperature Ts at dSb=3.7 and 4.5 nm. ν decreases monotonically with increasing dSb-1 in accordance with a model previously presented. When the thickness dAg of the silver sublayer is equal to 8.5×10-2 nm such parameters as the thicknesses ds0 and dv0 of surface regions near the substrate and the vacuum and the growth rates us and uv at surfaces adjacent to the substrate and the vacuum are estimated. Effective values of the activation energy for crystallization are estimated from the Arrhenius plot of ν.