Abstract
Halide perovskites have emerged as promising semiconductors for optoelectronic applications due to their exceptional optical absorption and defect tolerance. However, most studies rely on polycrystalline films, where uncontrolled grain boundaries and orientation hinder reproducibility and device stability. This thesis explores epitaxial growth as a route to achieve structural control in halide perovskite thin films using pulsed laser deposition (PLD), a solvent-free and stoichiometric technique enabling crystalline alignment on lattice-matched substrates.
The first part introduces the fundamental principles of epitaxy and its extension to halide perovskites. It discusses the structural and optical properties of both 3D and 2D perovskites, and outlines the motivation for epitaxial control to uncover intrinsic properties otherwise masked by disorder.
Chapter 3 demonstrates room-temperature epitaxy of MAPbI₃ on KCl substrates, revealing that highly oriented films can be obtained without thermal activation. The resulting cubic phase shows well-defined out-of-plane and in-plane alignment, verified by X-ray diffraction and reciprocal space mapping. Chapter 4 investigates the influence of growth temperature and deposition rate for transition from island to layer-by-layer growth through controlled deposition parameters and post-treatments, aiming to improve carrier mobility.
Chapters 5 and 6 extends epitaxial growth by PLD to other compositions. The successful deposition of 2D layered PEA₂PbI₄ and Sn-based perovskite CsSnI₃ highlights the versatility of the method. In CsSnI₃, epitaxial stabilization enables the formation of photoactive orthorhombic phase with twin-domain formation and a seed mediated growth. Overall, the results establish PLD as a viable technique to grow epitaxial halide perovskite thin films and heterostructures. The findings contribute to understanding strain effects, interface engineering, and growth kinetics, paving the way for future device integration and exploration of new perovskite phases under epitaxial constraint.
The first part introduces the fundamental principles of epitaxy and its extension to halide perovskites. It discusses the structural and optical properties of both 3D and 2D perovskites, and outlines the motivation for epitaxial control to uncover intrinsic properties otherwise masked by disorder.
Chapter 3 demonstrates room-temperature epitaxy of MAPbI₃ on KCl substrates, revealing that highly oriented films can be obtained without thermal activation. The resulting cubic phase shows well-defined out-of-plane and in-plane alignment, verified by X-ray diffraction and reciprocal space mapping. Chapter 4 investigates the influence of growth temperature and deposition rate for transition from island to layer-by-layer growth through controlled deposition parameters and post-treatments, aiming to improve carrier mobility.
Chapters 5 and 6 extends epitaxial growth by PLD to other compositions. The successful deposition of 2D layered PEA₂PbI₄ and Sn-based perovskite CsSnI₃ highlights the versatility of the method. In CsSnI₃, epitaxial stabilization enables the formation of photoactive orthorhombic phase with twin-domain formation and a seed mediated growth. Overall, the results establish PLD as a viable technique to grow epitaxial halide perovskite thin films and heterostructures. The findings contribute to understanding strain effects, interface engineering, and growth kinetics, paving the way for future device integration and exploration of new perovskite phases under epitaxial constraint.
| Original language | English |
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| Qualification | Doctor of Philosophy |
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| Award date | 17 Oct 2025 |
| Place of Publication | Enschede |
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| Print ISBNs | 978-90-365-6759-6 |
| Electronic ISBNs | 978-90-365-6760-2 |
| DOIs | |
| Publication status | Published - 17 Oct 2025 |