Abstract
This thesis describes an experimental study of conducting layers formed in gallium arsenide (GaAs) substrates by the implantation of dopant atoms. In particular p-type and n-type layers, formed by the implantation of cadmium (Cd) and tellurium (Te) respectively, have been studied in detail. Hall effect and resistivity measurements, in conjunction with layer removal techniques, have been used to characterise the carrier concentration and mobility within the implanted layer. The influence of various experimental conditions, in particular temperature of implant, total dose and post - implant annealing procedures, upon the electrical properties of the implanted layer is reported. Some detailed measurements of the electrical characteristics of damaged layers formed by heavy ion bombardment are also reported.