The nitridation of Co/Zn(002) ultrathin films was formed by 2 keV nitrogen ion sputtering. Interestingly, the effect of N-implantation in our observations only occurs for the substrate ZnO (002) initially covered by Co, and only for the off-normal ion incidence. The concentration of N saturated on the surface regime can reach more than 70%. In this method of growing the ultrathin Co-N films, the rapid disappearance of carbon contamination during the sputtering process was extremely obvious.