Formation of graphitic films on Cu(111) via electron beam induced deposition

BONETTO, F.; SILVA, C.; FERREIRA, E.H. MARTINS; CANDIA, A.; PASSEGGI, M.C.G.; MONTORO, S.; VIDAL, R.

VACUUM

PERGAMON-ELSEVIER SCIENCE LTD

Año: 2021 vol. 183 p. 109824 - 109834

0042-207X

Electron beam induced deposition using ethylene as precursor gas is used to generate carbonaceous films onCu(111). The study was performed in an ultrahigh vacuum chamber for two different precursor gas pressures,and two substrate temperatures. Auger electron spectroscopy and reflection electron energy loss spectroscopywere used to characterize the film growth process in-situ. These techniques allowed us to determine how the depositedfilm covers the Cu(111) substrate as a function of the ethylene exposure, obtaining a final coverage of upto 0.8 monolayer, depending on the growing conditions. Based on the CKLL Auger line shape and on the reflectionelectron energy loss (REELS) spectra we can conclude on the graphitic characteristics of the grown film and onthe optimum growing conditions: lower substrate temperature and higher ethylene pressure. Raman spectroscopyand scanning tunneling spectroscopy were used as ex-situ techniques to assess the properties of the grown film.Results from both techniques indicate that the film consists of small (10?20 nm in size) nanocrystals of few (1?2)layers graphene. Once optimized, this method may allow growing graphene with a predesigned pattern, withoutthe need to heat the substrate at high temperatures.