Applying slow positrons to the study of ion implantation induced defects in GaAs

The use of slow positron beams to study damage resulting from the ion implantation of GaAs is described in detail. The measurement of damage resulting from 125 keV Si+ is used as an example to demonstrate the sensitivity of the technique to implant fluences of <1×1011 cm−2. A method for extracting defect profiles is also described and it is shown that for the current measurements a defect tail extends into the sample, probably resulting from ion channelling. Specific uses of the positron technique relevant to GaAs device fabrication are given.