Epitaxial growth of thin gold films onto pure and doped NaCl and KCl substrates

Abstract

The influence of impurities such as calcium, strontium or silver ions present in the substrates on the structural growth features of continuous gold thin films, vacuum evaporated at constant deposition rates onto NaCl and KCl substrates heated in the temperature range from 90 to 300 °C, was studied by transmission electron microscopy and transmission electron diffraction. The epitaxial growth of gold thin films is inhibited by the presence of 5 × 10 -1 mol.% strontium or calcium ions in the KCl and NaCl substrates. The presence of 1.7 × 10 -1 mol.% silver ions in the NaCl substrates enhances the epitaxial growth of the gold thin films even at a substrate temperature of 120 °C. An enhancement of the gold thin film epitaxial growth is also obtained with NaCl-2 × 10 -2mol.%Ag-5 × 10 -1mol.%Ca and NaCl-1.7 × 10 -1mol.%Ag-5 × 10 -1mol.%Ca substrates.