Atom Probe Tomography (APT) is a microscopy method that is used to characterize materials by providing three-dimensional (3D) compositional imaging at near-atomic scale with high spatial and chemical sensitivity. APT is based on the field evaporation of atoms located at the surface of a sample that has previously been shaped into a sharp needle. The emitted atoms are detected using a time- and position-sensitive detector. As a time-of-flight mass spectrometry method, atoms are identified and their initial position within the structure of the material is reconstructed in 3D, following reconstruction algorithms.

The APT lab of NTNU is the first atom probe facility in Norway. It is a Norwegian national infrastructure, which was established in 2018 and funded by the Research Council of Norway (RCN) through the Norwegian Laboratory for Mineral and Materials Characterization (MiMaC) project. It is equipped with a Cameca 5000XS and it is located at the Department of Materials Science and Engineering. A wide range of materials are being analyzed using the APT facility at NTNU in various research and industrial projects. Projects involve materials from metallic materials such as superalloys and aluminium alloys, to batteries, oxides and minerals.

The APT lab has strong technical and academic support from Dr. Constantinos Hatzoglou and Associate Professor Paraskevas Kontis. Researchers who want to make use of the lab can receive support on planning their experiments and estimations on access costs required for their projects. We can also perform experiments to support your research and offer full training to users when this is necessary. As this is a national infrastructure, researchers and industries from all around the world can have access to the facility. You can simply contact us!

Since this is a national infrastructure, users have to acknowledge the contribution of the APT lab in any output, such as publications, master or PhD thesis, data etc., using the following statement:  “The Research Council of Norway (RCN) is acknowledged for funding the NTNU atom probe facility through the Norwegian Laboratory for Mineral and Materials Characterization (MiMaC) project number 269842.”

2022

• K.A. Hunnestad, C. Hatzoglou, Z. Khalid, P.E. Vullum, Z. Yan, E. Bourret, A.T.J. van Helvoort, S.M. Selbach, D. Meier, Atomic-scale 3D imaging of individual dopant atoms in an oxide semiconductor, Nature Communications 13 (2022) 4783.
• S. Shah, A. Gopal, E. Thronsen, C. Hatzoglou, B. Holmedal, Precipitation, mechanical properties and early slant ductile fracture in cyclic and naturally aged Al-Zn-Mg(-Cu) alloys, Materials & Design 222 (2022) 111026.
• S. Wu, H. S. Soreide, B. Chen, J. Bian, C. Yang, C. Li, P. Zhang, P. Cheng, J. Zhang, Y. Peng, G. Liu, Y. Li, H. J. Roven, J. Sun, Freezing solute atoms in nanograined aluminum alloys via high-density vacancies, Nature Communications 13 (2022) 3495.
• S. Shah, E. Thronsen, C. Hatzoglou, S. Wenner, C. D.Marioara, R. Holmestad, B. Holmedal, Effect of cyclic ageing on the early-stage clustering in Al–Zn–Mg(-Cu) alloys, Materials Science and Engineering: A 846 (2022) 143280.

2021

• A. Lervik, E. Thronsen, J. Friis, C. D. Marioara, S. Wenner, A. Bendo, K. Matsuda, R. Holmestad, S. J. Andersen, Atomic structure of solute clusters in Al–Zn–Mg alloys, Acta Materialia 205 (2021) 116574.
• J. K. Sunde, C. D. Marioara, S. Wenner, R. Holmestad, On the microstructural origins of improvements in conductivity by heavy deformation and ageing of Al-Mg-Si alloy 6101, Materials Characterization 176 (2021) 111073.

The APT lab is currently based at the Department of Materials Science and Engineering (Kjemi block 1) and it is equipped with a Cameca 5000XS. For APT sample preparation, the lab has electropolished facilities and established protocols for the preparation of samples when site-specific microstructures are not needed to be investigated. For site-specific sample preparation, we and other users use the dual beam Focused Ion Beam (FIB) microscopes located at the NTNU NanoLab.

Users that want to use the Nanolab, they will have to request access and training following the procedures of Nanolab. In coordination with the Nanolab, we will offer support on methods preparing APT samples using the FIB facilities. In addition, users can make use of a plasma FIB that was recently installed at NTNU outside of the Nanolab cleanroom and it is expected to be operational soon. For details about the PFIB you can contact Dr Hamid Khanmohammadi. Site-specific sample preparation also allow us to prepare APT samples for correlative TEM/APT studies, where users can benefit from the TEM facilities at the TEM Gemini Centre. The APT lab has all the necessary sample holders to perform correlative TEM/APT studies.

For APT data analysis, the APT lab is using the AP-Suite software provided by Cameca. Dr Constantinos Hatzoglou has also developed the Norwegian Atom Probe App (NAPA) software. NAPA is an open access software developed in MATLAB and it is dedicated to APT data treatment. This is a complementary tool to the data treatment solutions offered by CAMECA. It supports different formats of APT data files (.pos, .epos and .ato) and range files (.env and .rrng). NAPA has many tools that the users can easily apply thanks to an interface (see figure). Specific tools adapted to user requests can also be added.

For any questions regarding NAPA, please contact Dr Constantinos Hatzoglou.

Screenshot of the NAPA user interface showing an example of identifying edge clusters (by using Iso Position Method) in APT datasets, according to the Jenkins et al. method.

In the APT lab, users with various scientific questions seek to gain insights into different materials. APT provides a 3D compositional imaging at near atomic scale with high spatial and compositional resolution. That allow us to investigate for instance, segregation of solutes at grain boundaries and other crystal defects, such as dislocations, phase partitioning, cluster analysis and spatial mapping of trace elements or dopants. These are only a few examples of information that can be extracted from APT data.

For more information and organizing an experimental plan, please contact us. Examples of materials that we are currently working on, and not limited to, are superalloys, batteries, aluminium alloys, semiconductors and others.

The APT lab is located in the K1-building at Realfagbygget on campus Gløshaugen

Address

Sem Sælands vei 14
7034 Trondheim
Norway