ANTIMONY DOPED GAAS - ROLE OF THE ISOELECTRONIC DOPANT IN DEFECT EVOLUTION

Metalorganic vapor phase epitaxial GaAs:Sb layers and Schottky barrier structures based on them have been investigated regarding defect evol ution versus doping level. Three types of defects are considered such as surface morphology imperfections, structural defects in the epilaye rs, and interface defects at the Schottky barriers. A correlation betw een the defect behavior in the layers and the Schottky structures has been observed. It has been shown that an optimal Sb doping region exis ts where the defect density decreases compared with the undoped and hi ghly Sb doped samples. The dominating defects in the Schottky barrier interface are dislocation-related states which can be effectively infl uenced by the isoelectronic doping. (C) 1996 American Vacuum Society.