Annealing effect on structural and magnetic properties of Tb and Cr co-implanted AIGaN

Unintentionally doped AIGaN layers, which were co.implanted with 400 keV Tb＋ ions and 200keV Cr＋ ions at doses of 1.5×1015cm-2, have been rapid thermally annealed at 800℃ and 900℃ for 5 min in flowing N2, Compared with Tb implanted AIGaN sample, the Tb and Cr co-implanted sample revesls a larger magnetic signal. In this work, the annealing effect on the structural and magnetic properties of Tb and Cr co-implanted AIGaN thin films have been studied. XRD and raman scattering results indicate that no second phase presents in thetin films and mast of the implantation induced defects can be removed by post-implantation annealing. Superconducting quantum interference device （SQUID） measurements show clear room temperature ferromagnetic behavior and an increase in the saturation magnetization as a result of annealing. The saturation magnetization of the 900℃ annealed sample is about 15 times higher than that of the 800℃ annealed sample.