Minority-Carrier Investigations of Beam-Annealed and Thermally-Annealed Semiconductors

摘要

The effect of beam-processing on III-IV compound semiconductors, particularly indium phosphide(InP), has been investigated in detail. Two types of beams have been used to anneal ion-implantation damage in these materials, scanned CW Argon ion laser beams, and incoherent radiation focussed on the sample. Two different but related problems have been addressed. (1) The problem of accurately measuring the equilbrium temperature of the sample in the region that is heated by a focussed CW laser beam has been studied using novel techniques: in-situ high-temperature photoluminescence and Raman-scattering measurement. Accurate temperature measurements for this case have been obtained for the first time; far less spatial dependence of the thermal profiles has been observed than is predicted by existing theories, which neglect important effects such as carrier diffusion. (2) Rapid thermal annealing of ion-implanted InP was studied for a variety of implant and anneal conditions using low-temperature photoluminescence, Raman scattering, and Rutherford backscattering. The results of all three of these characterization techniques were self-consistent, and showed that, in order to obtain single-crystal material with high electrical activation, it is necessary to perform the implants at an elevated temperature (approx. 200 C) and to anneal at as high a temperature as possible without causing significant dissociation.