Structural and magnetic properties of cubic GaCrN (c-GaCrN) grown on MgO (0 0 1) substrate by plasma-assisted molecular beam epitaxy (PAMBE) were studied with X-ray diffraction (XRD), X-ray absorption fine structure (XAFS) analysis and a superconducting quantum interference device (SQUID) magnetometer. The Cr concentration dependence of XRD rocking curve showed that high Cr-doping induced mosaic block effect in the c-GaCrN layer. It was found that the saturation magnetization (M-s) and the coercive field (H-c) obtained from the M-H curves decrease with increase in the Cr concentration. XAFS results showed that the ratios of Cr atoms substituted for Ga sites to Cr atoms incorporated in low Cr-doped samples (Cr similar to 0.2%) are higher than those in highly Cr-doped samples (Cr similar to 3%), and that the other Cr atoms are segregated to form a CrN phase with NaCl structure. This XAFS results correspond to the SQUID data that the amounts of magnetically active Cr atoms in c-GaCrN decrease for the highly Cr-doped samples. X-ray absorption near-edge structure spectra also supports these results. (c) 2006 Elsevier B.V. All rights reserved.