Bismuth Thin Film Growth on Salts and the Pursuit of Topological Insulators

The search for topological insulators has intensified over the last couple of years. One of the candidates theorized to be a topological insulator are bilayers of bismuthene, the bismuth analogue of graphene. During the bachelor project, multiple thin films of Bismuth were grown and their quality under the influence of underlying substrates of NaCl(001) and BaF2(111) has been investigated. Growth was achieved in a high vacuum Thermal Evaporator. The topography of substrates and grown films were analyzed using Atomic Force Microscopy. A large part of the project was focused on restoring a UHV system in which thin films could be grown and analyzed. This system will help improve the quality of the films and therefore improves the chances of producing a sufficiently large sample for electronic measurements. The cleaved barium-fluoride produces ultra-flat plateaus optimal for growth. The grains grown on the barium-fluoride substrates were larger in two-dimensional sizes than the grains...Show moreThe search for topological insulators has intensified over the last couple of years. One of the candidates theorized to be a topological insulator are bilayers of bismuthene, the bismuth analogue of graphene. During the bachelor project, multiple thin films of Bismuth were grown and their quality under the influence of underlying substrates of NaCl(001) and BaF2(111) has been investigated. Growth was achieved in a high vacuum Thermal Evaporator. The topography of substrates and grown films were analyzed using Atomic Force Microscopy. A large part of the project was focused on restoring a UHV system in which thin films could be grown and analyzed. This system will help improve the quality of the films and therefore improves the chances of producing a sufficiently large sample for electronic measurements. The cleaved barium-fluoride produces ultra-flat plateaus optimal for growth. The grains grown on the barium-fluoride substrates were larger in two-dimensional sizes than the grains grown on sodium-chloride. Further research is required to obtain the crystalline configuration of these grains.Show less

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Bismuth Thin Film Growth on Salts and the Pursuit of Topological Insulators