In this paper we present structural and electrical investigations on high temperature Fe-implanted InP. The aim of the work is to relate the lattice position of the implanted atoms after annealing treatments (from 300to600°C) with their electrical activation as compensating deep traps and to draw a comprehensive picture of the activation mechanisms. The overall results demonstrate that the electrical behavior and the Fe2+ deep trap activation properties are strictly connected to the annealing evolution of the implant-induced damage and to the escape process of the Fe atoms from substitutional sites, which in turn is controlled by the background doping density in the substrates.