An ion-assisted deposition system for use in the fabrication of submicron dimension device ohmic contacts

Abstract The design and characterisation of a novel ion-assisted deposition system for use in the fabrication of ohmic contacts to submicron dimension devices is described. The system is based on a conventional electron beam evaporator, which was modified to simultaneously evaporate and partly ionise the contact metallisation. The substrate holder is biased in order that the deposition of the contact metallisation upon the substrate occurs under the influence of low energy ion bombardment. Estimated ionisation efficiencies as high as 7% and ion doses of 5 × 10 15 ions cm −2 have been obtained using Ge as the source material.