SIMS characterization of segregation in InAs/GaAs heterostructures

We performed a detailed study of in situ indium segregation in InAs/GaAs heterostructures during conventional MBE growth process. A set of heterostructures grown under different substrate temperatures was tested. We used in the study a recently developed equation for SIMS's Depth Resolution Function (DRF), which included Recoil Implantation, Cascade Mixing and Sputtering Induced Roughness phenomena (RMR model). Segregation process was included in this DRF as an exponentially increasing function. Then we found from experimental SIMS depth profiles segregation parameters for different growth temperatures and the energy activation for the segregation process. It was found equal to 0.27 eV that is close to values published in literature. A segregation free regime of the growth process was developed experimentally. (C) 2008 Elsevier B.V. All rights reserved.