10 keV heavy ion irradiation induced magnetic modification in Co/Alq3 bilayer

Ion irradiation induced magnetic modification of a Co (100 Å)/Alq3 (950 Å) bilayer thin film has been studied using magneto optic Kerr effect (MOKE) studies. Alq3 film was deposited on Si(100) substrate using thermal evaporation deposition technique. Then, Co thin film was deposited on top of Alq3 film using e-beam evaporation. 10 keV Ar+ ion beams with a fluence of 1 × 1016 ions/cm2 have been used to modify the Co/Alq3/Si bilayer sample. MOKE measurements were performed from the sample before and after ion irradiation. MOKE measurements reveal that Kerr intensity reduces by a factor of three without any observable change in coercivity after irradiation. The observed change in the magnetic property is due to the Ar ion implantation and mixing between Co and Alq3 at the Co/Alq3 interface. Monte Carlo simulation code SRIM 2008 is used to understand the Ar distribution in the sample and mixing of the two materials at the interface.