Heavy ion implantation into InP and In0.53Ga0.47As and rapid thermal annealing has been applied to produce materials with high resistivity, good mobility and ultrashort carrier lifetime, as required for ultrafast optoelectronic applications. Two implantation methods have been analyzed: Fe+ implantation into semi-insulating InP and InGaAs, and P+ implantation into p-doped InP and InGaAs. Both approaches allow production of layers with high sheet resistance, up to 10(6) Omega/square for the P+-implanted compounds. Electron mobility in the high resistivity layers is of the order of 10(2) cm(2)V(-1)s(-1). Carrier lifetimes, measured by the time-resolved photoluminescence and reflectivity, can be tuned from similar to100 femtoseconds to tens of picoseconds by choosing implantation and annealing conditions. Measurements of carrier dynamics have shown that carrier traps act as efficient recombination centers, at least for the case of InP. The dependencies of electrical and ultrafast optical properties on the implantation dose and annealing temperature are determined by the interplay between shallow P and As antisite-related donors, deep Fe-related acceptors and defect complexes.