Whether it is applicable to utilize for the structural study of Quantum Dot?
I am assuming your question is related to Atom Probe "Tomography". APT and TEM are complementary techniques. APT has an atomic layer resolution in the depth direction. APT can provide 3D elemental maps (including light elements), so you can measure composition of particles, their distribution and morphology. It can show chemical gradients and segregation along defects or interfaces. An APT sample has a needle shape with a volume on the order of ~50x50x200 nm3. TEM has a larger field of view, it can give crystallographic information. S/TEM using EDS or EELs can give chemical mapping but these are rather qualitative.
Atom Probe Tomography has been applied to study QDs such as in these publications: http://dx.doi.org/10.1016/j.actamat.2015.10.048
https://doi.org/10.1103/PhysRevB.83.205308
Hello, just to add some element to the two previous answers . In some cases it is possible to study the same specimen by STEM (in high resolution, or in electron tomography mode) and by APT. In this case the complementarity of the two techniques becomes extremely powerful. For instance, the MPIE group applied this approach to the study of grain boundaries in metals. At GPM Rouen, we studied QWs and QDs in this way. The TEM images allow obtaining a good spatial accuracy of APT 3D reconstruction, they also allow determining the crystal orientation and the presence of defects such as stacking faults or dislocations, that are not always visible by APT. APT yields then the 3D chemical landscape. The ensemble of these complementary data can be used to build valence and conduction band landscapes from which the electronic or optical properties of these heterostructures can be retrieved. In several studies, we could assess the role of defects and non-random alloy distribution in III-N quantum confined systems. Here’s some reference related to these issues :
https://www.researchgate.net/publication/318545129_Three-dimensional_atomic-scale_investigation_of_ZnO-Mg_x_Zn_1-x_O_m-plane_heterostructures
https://www.researchgate.net/publication/317960021_Carrier_Localization_in_GaNAlN_Quantum_Dots_As_Revealed_by_Three-Dimensional_Multimicroscopy
https://www.researchgate.net/publication/306920593_Statistical_nanoscale_study_of_localised_radiative_transitions_in_GaNAlGaN_quantum_wells_and_AlGaN_epitaxial_layers
https://www.researchgate.net/publication/292187602_Multi-microscopy_study_of_the_influence_of_stacking_faults_and_three-dimensional_In_distribution_on_the_optical_properties_of_m-plane_InGaN_quantum_wells_grown_on_microwire_sidewalls
https://www.researchgate.net/publication/292187602_Multi-microscopy_study_of_the_influence_of_stacking_faults_and_three-dimensional_In_distribution_on_the_optical_properties_of_m-plane_InGaN_quantum_wells_grown_on_microwire_sidewalls
- Badges
- Science topic
- Similar topics
- Physical Sciences
- Materials Science