Damage distribution in GaAs implanted at elevated temperature

Abstract

Wafers of (100) GaAs have been implanted with 140 keV Zn + ions at off-channeling direction up to a fluence of 1×10 14 cm −2. The target temperature was kept at 110±10° C. The defect clusters and the damage depth distributions were investigated by planar and cross-sectional high-resolution transmission electron microscopy (HRTEM and XHRTEM) and were modelled by a MAR-LOWE-based computer code. The experimental mean depth of the damage profile located at about 85 nm exceeds the calculated deposited energy and vacancy distributions by more than 50%. The correlation between the deposited energy density within the cascade and the inner structure of the observed defect clusters is discussed.