| AVS 65th International Symposium & Exhibition | |
| Applied Surface Science Division | Tuesday Sessions |
| Session AS+BI-TuM |
| Session: | Applied Surface Science: From Electrochemistry to Cell Imaging, a Celebration of the Career of Nicholas Winograd |
| Presenter: | Maiglid Andreina Moreno Villavicencio, Univ. Grenoble Alpes, CEA, LETI, France |
| Authors: | M.A. Moreno Villavicencio, Univ. Grenoble Alpes, CEA, LETI, France N. Chevalier, Univ. Grenoble Alpes, CEA, LETI, France J.-P. Barnes, Univ. Grenoble Alpes, CEA, LETI, France I. Mouton, Univ. Grenoble Alpes, CEA, LETI, France F. Bassani, Univ. Grenoble Alpes, CNRS, LTM, France B. Gautier, Université de Lyon, INSA Lyon, Institut des Nanotechnologies de Lyon, UMR CNRS 5270, F- 69621 Villeurbanne cedex, France |
| Correspondent: | Click to Email |
In dual-beam time-of-flight secondary ion mass spectrometry (ToF-SIMS) depth profiling, a succession of two-dimensional chemical images is acquired. The provided images can be used to generate a three-dimensional (3D) visualization of the sputtered volume. However, standard reconstruction methods do not take into account the initial sample topography or lateral variations in sputter rates.
Due to geometry and the diversity of materials the resulting 3D chemical visualization of heterogeneous and non-planar samples may be distorted. To address this issue ToF-SIMS analysis was combined with atomic force microscopy (AFM). This combination supplies the missing sample topography of the ToF-SIMS images and allows the calculation of sputter rates for the materials present in the sample.
To achieve an accurate 3D ToF-SIMS reconstruction a protocol was developed that combines AFM topographical images, crater depth measurements and sequences of ToF-SIMS images, all acquired on the same area of the sample. This combined ToF-SIMS/AFM methodology was applied to a sample consisting of GaAs selectively grown in SiO2 patterned structures using MOCVD. The initial topography revealed that the GaAs areas were higher than SiO2 patterns, and the large sputter rate differences (up to a factor 2) mean that a simple reconstruction (flat surface and constant sputter rate) leads to severe distortions in the 3D ToF-SIMS reconstruction.
Using the combined methodology, a 3D overlay between AFM and ToF-SIMS images at each interface can be made and the local sputter rate can be mapped. Finally, a protocol was developed for the correction of the 3D ToF-SIMS reconstruction and depth-profiles within a rendered volume defined by successive AFM imaging.
This work was carried out on the nanocharacterisation platform (PFNC) of the CEA Grenoble and this project has received funding from the European Union’s Horizon 2020 research and innovation programme under grant agreement No 688225.
References:
Moreno, M. A. et al. Combined ToF-SIMS and AFM protocol for accurate 3D chemical analysis and data visualization. J. Vac. Sci. Technol. B Nanotechnol. Microelectron. Mater. Process. Meas. Phenom. 36, 03F122 (2018).