Samira Dorri

My PhD project at Thin Film Physics division at Linköping University focuses on synthesizing single crystal superlattice neutron supermirrors which is in particular suitable for supermirror Fermi choppers. By improving the performance of key neutron optical components, the flux of useful neutrons delivered to the sample is expected to increase significantly. Supermirror Fermi choppers can provide an attractive solution to the low flux problem at pulsed sources e.g., ESS. The project includes:

  • Growth of superlattice supermirrors by Ion-assistance direct current (DC) magnetron sputtering.
  • In-house structural (XRD, TEM), chemical (XPS), and plasma characterizations with the emphasis on understanding and improving the growth process to obtain the superlattice structure.
  • Isotopic and elemental analyses by ToF-ERDA and RBS measurements at Uppsala University.
  • Neutron reflectivity and multiple-energy neutron reflectometry measurements of selected multilayers at large-scale facilities.
  • Simulations using GenX and BornAgain software, to determine for example the interface widths, and in-plane and out-of-plane roughness correlations.
  • More detailed studies of the superlattice structure and interfaces with a sub-nm depth-resolution using specialized techniques such as GISANS and GISAXS.

During my master study in Jens Birch group at Thin Film Physics division, I gained experience about synthesizing nanocomposite, multilayer, and superlattice thin films using DC magnetron sputtering. And also, different characterization techniques such as XRD (theta-2theta, RC, pole figure, phi scan, RSM), XRR, TEM sample preparation, IBA (ERDA and RBS), and stress and nano-mechanical measurements.

University: Linköping University

PhD thesis: The route towards perfection of multifunctional artificial CrB2/TiB2 superlattices; stoichiometry, structure, and layer definition

Publications

Artificial superlattices with atomically abrupt interfaces by monolayer-controlled growth kinetics during magnetron sputter epitaxy, case of CrB2/TiB2, S. Dorri, O. Nyqvist, J. Palisaitis, A. Vorobiev, A. Devishvili, P. Sandstrom, N. Ghafoor, P.O.Å Persson, F. Eriksson, J. Birch. Materials and Design, https://doi.org/10.1016/j.matdes.2025.113661

TiB1.8 single layers and epitaxial TiB2-based superlattices by magnetron sputtering using a TiB (Ti: B= 1: 1) target, S. Dorri, J. Palisaitis, Szilárd Kolozsvári, Peter Polcik, P.O.Å Persson, N. Ghafoor, F. Eriksson, J. Birch Surface and Coatings Technology. https://doi.org/10.1016/j.surfcoat.2024.131534

Competitive co-diffusion as a route to enhanced step coverage in chemical vapor deposition, A. Haridas Choolakkal, P. Niiranen, S. Dorri, J. Birch, H. Pedersen, Nature Communication 15, 10667 (2024), https://doi.org/10.1038/s41467-024-55007-1

Enhanced quality of CrB2/TiB2 superlattices by controlling the B-stoichometry during sputter deposition, S. Dorri, J. Palisaitis, N. Ghafoor, F. Eriksson, P.O.Å Persson, J. Birch. Applied Surface Science. https://doi.org/10.1016/j.apsusc.2024.159606

Chemically homogeneous boron carbide 10B/11B isotope modulated neutron interference mirrors, J. Birch, S. Stendahl, S. Dorri, A. Zubayer, N. Ghafoor, F. Eriksson, https://doi.org/10.48550/arXiv.2404.04934

Effects of stoichiometry and individual layer thickness ratio on the quality of epitaxial CrBx/TiBy superlattice thin films. Materials and Design, S. Dorri, J. Birch, F. Eriksson, J. Palisaitis, B. Bakhit, P.O.Å Persson, L. Hultman, N. Ghafoor. https://doi.org/10.1016/j.matdes.2023.111842

Phase separation paths in metastable Zr1-xAlxN monolithic layers compared to multilayers with TiN: growth versus annealing temperatures, N. Ghafoor, S. Dorri, L. Hultman, J. Palisaitis, L. Rogström, B. Bakhit, G. Greczynski, J. Birch, Materialia. https://doi.org/10.1016/j.mtla.2023.101758

Oxidation Kinetics of Overstoichiometric TiB2 Thin Films Grown by DC Magnetron Sputtering. Corrosion Science, S. Dorri, J. Palisaitis, G. Greczynski, L. Hultman, J. Birch, B. Bakhit. https://doi.org/10.1016/j.corsci.2022.110493

Multifunctional ZrB2-rich Zr1-xCrxBy thin films with enhanced mechanical, oxidation, and corrosion properties, B. Bakhit, S. Dorri, A. Kooijman, Zh. Wu, J. Lu, J. Rosen, J. M.C. Mol, L. Hultman, I. Petrov, G. Greczynski, Vacuum. https://doi.org/10.1016/j.vacuum.2020.109990