The bombardment of solid surfaces with ions in the energy range below about 150 eV, depending on the ion-substrate combination, results in a net growth of material on the surface. An ion beam facility capable of producing highly uniform, low energy beams of current densities in the range 10−2 to 1 Am−2 has been developed to study the potential of this growth technique for the fabrication of thin epitaxial films at low temperatures.
The energy deposition associated with ion bombardment, which is considered to be responsible for the low temperature epitaxy capability, can also cause atomic displacements on the surface and near-surface regions of the substrate during initial growth and in the growing film. A study of the growth processes thus requires investigation of the damaging effects of low energy ion bombardment. In the present paper, fundamental aspects of the implantation and deposition of materials using very low energy ions will be discussed.