Facile fabrication of defect-induced 2D-stanene/stanene-oxide nano-sheet structure material through etching of SnOx thin film by the process of successive Ar+ ion sputtering

Abstract

In-situ Ar + -ion etching process is used to extract the defect-induced ultrathin 2D-stanene/stanene-oxide structured nano-materials from transparent conducting tin-dioxide (SnOx) thin films by KRATOS SUPRA spectrometer measurement system. In each etch-cycle during in situ successive Ar + -ion sputtering process, x-ray photoelectron (XPS) and ultraviolet photoemission spectroscopy (UPS) were measured and confirmed the formation of different crystal structures of defect-induced 2D-stanene and/or 2D-stanene oxide ultra-thin films. In situ XPS and UPS spectral results confirmed the formation of different defectinduced oxidation states of "Sn" and their change of density of states, valence band maximum and work functions of the extracted defect-induced ultra-thin 2D-stanene/stanene-oxide films. During etching process (τ etch = 0-4000 s) the thickness is changes from 200 nm (SnOx) → ≈2.5 nm (2D-Stanene). These results, further revealed with the ex-situ Raman spectra measurements, where we have observed that the 2D-stanene/stanene-oxide is extracted from SnOx thin films by this successive Ar + -ion etching process. This process provides an option to realize aggressively scaled nanostructure device-based 2D-stanene/ stanene-oxide materials with high-precision control that could be useful for fabrication of future electronic devices.