Structural and magnetic impact of Cr+-implantation into GaN thin film

Thin films of GaN with thickness of 2 μm were synthesized on sapphire. Cr+ ions were implanted into GaN with150 keV energy at a fluence of 3 × 1015 cm−2. The annealing of the samples was carried out for a short time using rapid thermal annealing (RTA). Structural properties of the implanted samples were undertaken by XRD and Rutherford backscattering. The annealed samples demonstrated lattice recovery and damages caused by implantation. The structural properties were also studied by High-resolution X-ray Diffraction (HRXRD). Magnetic measurements of the samples were performed by Alternating Gradient Magnetometer (AGM) at room temperature and by SQUID in the range of 5–380 K. The SQUID results showed ferromagnetic behavior at T = 5 K and above 380 K for Cr+-implanted GaN.

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► Epitaxial grown GaN was implanted with Cr+ ions at fluence 3 × 1016 cm−2 and annealed for activation of dopant.
► Structural characterization showed recovery implantation-induced damages and possible GaCrN phase formation.
► Magnetic study confirmed the ferromagnetic behavior of the samples at room temperature.
► Dilute magnetic semiconductors has been achieved with the highest TC above 380 K for Cr+-implanted GaN.