| AVS 61st International Symposium & Exhibition | |
| 2D Materials Focus Topic | Thursday Sessions |
| Session 2D-ThP |
| Session: | 2D Materials Poster Session |
| Presenter: | Alexander Merkulov, CAMECA, France |
| Authors: | A.V. Merkulov, CAMECA, France F. Horreard, CAMECA, France W. Strupinski, ITME, Poland A. Davis, CAMECA Instruments Inc |
| Correspondent: | Click to Email |
Characterization of graphene forms an important part of graphene research and involves measurements based on various microscopic and spectroscopic techniques. Characterization involves determination of the number of layers and the purity of sample in terms of absence or presence of defects or doping species.
A quantitative estimation of the layer thicknesses can be obtained using attenuated secondary electrons emitted from the substrate. Transmission electron microscopy (TEM) can be directly used to observe the number of layers on viewing the edges of the sample, each layers corresponding to a dark line. The information on the defectness of the graphene layer or presence of dopant species can be provided by surface sensitive technique such as XPS and SIMS (Secondary Ion Mass Spectrometry).
The extreme sensitivity of SIMS to any doping constituents in the surficial layer could provide the important information, difficult to obtain by other technique. Application of SIMS to graphene is not yet established. This work is having the goal to advance in finding an approach for graphene layers characterization.
SIMS is a destructive technique based on physical sputtering and consecutive ionization of sputtered atomic or molecular particles. All problems inherent to sputtering itself, such as recoil mixing and ion enhanced diffusion reduce the depth resolution necessary for monoatomic layers characterization. In order to avoid such effect, an Extremely Low Impact Energy (EXLIE) ion beam approach is employed in our experiments. Sputtering with different ionic species and under different angles is performed, targeting the best possible depth resolution in graphene layers.
These EXLIE SIMS measurements are among the first SIMS results obtained on such structures. SIMS as many of the characterization processes needs subsequent tests to determine the validity of the results, using different SG, FG and SLG structures. The SIMS quantification aspects will be also discussed.