High energy light ion (HELI) irradiation has been used for modification and engineering of defects in semiconductors. Different structural and electrical characterizations have been employed to monitor the effect of irradiation. We have shown that the energy lost by HELI in GaAs and InP is not sufficient to introduce bulk defects in GaAs. In contrast, defect creation and annihilation scales with the nuclear energy loss, even the energy transfer is lower than the lattice binding energy. This observation has been corroborated by establishing the similarity between the damage creation by HELI and very low energy Ar ion irradiation, where the energy loss is predominantly by nuclear process.