Investigation of FIB irradiation damage in La0.7Sr0.3MnO3 thin films

In this work we analyse systematically how morphological and magnetotransport properties of manganite thin films are affected by the damage induced by focused ion beam (FIB) irradiation. We irradiate different areas of the same sample with doses ranging from 5×10¹² to 3×10¹⁷ ions/cm² and we find that the film becomes swollen for doses up to 10¹⁶ ions/cm² and is eventually eroded by ion milling for further irradiation. On the other hand, transport properties are much more sensitive to FIB irradiation: the metal–insulator transition temperature is found to decrease monotonically with increasing doses up to 1.8×10¹³ ions/cm². At doses higher than 5.6×10¹³ ions/cm² the metallic state is completely suppressed and likely, also ferromagnetism.