▎ 摘　　要

One of the major challenges in the realization of electronic devices consisting of 2D materials produced using chemical vapor deposition (CVD) is the transfer of the 2D material from the growth catalyst to a relevant support material. However, the current steps of removing contamination from the transfer process is rarely fully effective with trace PMMA residue usually remaining. In this study, we explore the use of size selected argon gas clusters to clean polymer residue from CVD-grown commercial graphene samples. The energy per Ar atom can be tuned to <0.5 eV/atom, significantly below the bond strength of the graphene but sufficiently energetic to remove polymer material. Two of the primary techniques for characterizing the quality of graphene materials in terms of both chemical properties and physical properties are X-ray photoelectron spectroscopy (XPS) and Raman spectroscopy, respectively. However, these are typically ex situ measurements and results can be heavily influenced by exposure of the samples to atmospheric conditions prior to measurement. However, by in situ monitoring the cleaning process through the use of a combined XPS and Raman spectroscopy system, coupled with an argon gas cluster ion beam (GCIB) and capable of carrying out each measurement simultaneously, this allows us to explore in detail any modifications to the graphene layer during the GCIB cleaning process. This investigation is further enhanced with additional time-of-flight secondary ion mass spectrometry (ToF-SIMS) imaging. Both the presence and removal of surface contamination is shown, and the level of defects being introduced into the graphene layer, as a result of the sputtering process, is monitored in real-time. We show that by keeping the energy per argon atom less than 1 eV, we can prevent the introduction of defects to the graphene layer, as well as efficiently remove contamination present on the graphene surface.