In this paper, using high-dose implantation of O2+ ions, nano-sized WO3 films were obtained on the surface and at various depths of W(111) for the first time. It has been confirmed that when O2+ ions are implanted into W at room temperature with low energy, partial formation of oxides such as WO, WO2, WO3 and WO4 occurs. It has been proved that in order to obtain a homogeneous and good stoichiometry of W oxide, it is necessary to carry out oxidation at a certain temperature. The optimal modes for obtaining hidden oxide layers in the near-surface region of tungsten, the substrate temperature W, the energy and dose of O2+ ions were determined. The concentration profiles of distributed O atoms in depth were studied for the three-layer W-WO3-W(111) system. Using scanning electron microscopy, the formation depths and thicknesses of WO3 layers were determined. The WO3 films were polycrystalline. The resulting films have potential for creating thin-film OLED displays, as well as nanofilm MOS transistors.