Damage depth-profiling of Au+ and O+-irradiated amorphous PEEK by monoenergetic positron beams

Amorphous poly(aryl-ether-ether ketone) (PEEK) irradiated with 2 MeV Au+ and O+ ions was exposed to positron beams to measure the positron annihilation Doppler broadening as a function of the positron energy. As in the previous case of O+-irradiated semicrystalline PEEK, the annihilation lines recorded at relatively low positron energies became broader with increasing irradiation dose. The thickness of the damaged layer estimated from the positron data was compared with the mean depth of the implanted ions calculated by the TRIM code. For the Au+-irradiated samples, some discrepancy was observed between the two quantities. (orig.)