Photoluminescence and positron annihilation spectroscopy of MeV Si+ ion-irradiated SiyO1−y:Er (y≈1/3) thin films

Amorphous erbium-doped silicon oxide (SiyO1−y:Er, y≥1/3) thin films are currently under investigation as a luminescent material system for complementary metal-oxide semiconductor compatible light emitters. We have grown films with y≈1/3 and investigated their properties using both positron annihilation and photoluminescence (PL) spectroscopies. Films were characterized “as deposited,” following irradiation with 1 MeV Si+ ions and after isochronal annealing. The PL yield from both Er3+ ions and sensitizing defects is reduced by irradiation, depending strongly on the irradiation fluence and reaching saturation at ∼4×1013 Si+/cm2. Higher implantation fluences result in an open-volume defect structure in the film that persists after annealing. This annealing behavior is similar to that of an unrecoverable quenching effect on Er3+-related PL near 1540 nm, and we suggest that these open-volume defects may cause a decoupling of the Er3+ ions from sensitizing oxide point defects that form as a result of the film deposition process.