Reordering of implanted amorphous layers in gaas

Channeling measurements have been utilized to investigate the reordering of amorphous layers produced by implantation of 100 keV Zn or 400 keV Se ions at a dose of 3 × 1013 ions/cm2 into GaAs substrates at LN2 temperatures. Annealing was carried out at temperatures between 200 and 600°C for <100>, <111> and <110> oriented substrates. From the results of annealing experiments we conclude that reordering of amorphous layers is not a simple epitaxial regrowth process as is found for implanted Si and Ge. Analysis with X-ray diffraction and TEM techniques show that the reordered layer is epitaxial on the underlying substrate but appreciable disorder in the form of sub-structure is present.