Study of manganese accumulation in ion implanted GaAs influenced by Fermi energy and annealing technique

The redistribution of Mn during post-implantation annealing in bulk semi-insulating GaAs and GaAs vapor phase epitaxial buffer layers is studied by secondary ion mass spectrometry for Si, Se, and Cd implanted materials annealed capless in an As₄-H₂ atmosphere. The secondary ion mass spectrometry chemical profiles are correlated to the electrical profiles of the implanted layers and agree with the stages of approach toward equilibrium during annealing. We have developed a model for Mn diffusing by an interstitial-substitutional mechanism and one that agrees with the relative amount and type of implantation damage due to stoichiometric disturbances generated during the implantation process. Mn accumulation caused by differences between donor and acceptor implants, the effects of annealing temperature, time, and atmosphere are discussed. The implant fluences used in this investigation are appropriate for GaAs field-effect transistor device applications.