Transmission Electron Microscopic Observation of Microdefects in Zn+-Implanted GaAs

Abstract
Transmission electron microscopic (TEM) observation of GaAs implanted with 100 keV Zn+ ions to 1014 ∼1015 ions/cm2 and annealed at 650 ∼950^°C by capless annealing in As ambient revealed precipitates, stacking-fault tetrahedra (SFTs) and stacking-fault pyramids (SFPs). The precipitates, distributed from near R p to greater depths, consisted of non-crystalline material of mean inner potential smaller than that of GaAs. Defects showing black-white contrast were found to be SFTs accompanied by a precipitate or SFPs. Two types of SFTs can be differentiated by the core structure of their stair-rod dislocations. Most of the SFTs observed were identified as β-SFTs, and very few SFPs were observed.