We report on the process of low energy N-2(+) implantation and annealing of a Cu(0 0 1) surface. Through AES we study the N diffusion process as a function of the substrate temperature. With STM and LEIS we characterize the surface morphology and the electronic structure is analyzed with ARUPS. Under annealing (500 < T < 700 K) N migrates to the surface and reacts forming a CuxN compound that decomposes at temperatures above 700 K. LEIS measurements show that N locates on the four-fold hollow sites of the Cu(0 0 1) surface in a c(2 x 2) arrangement. Finally, a gap along the [0 0 1] azimuthal direction is determined by ARUPS. DFT calculations provide support to our conclusions. (C) 2011 Elsevier B. V. All rights reserved.